Merged default into bug24622

156 files changed, 5408 insertions, 2820 deletions

diff --git a/LICENSE-MPL-RabbitMQ b/LICENSE-MPL-RabbitMQ
index 14bcc21d..d50e32ef 100644
--- a/LICENSE-MPL-RabbitMQ
+++ b/LICENSE-MPL-RabbitMQ
@@ -447,7 +447,7 @@ EXHIBIT A -Mozilla Public License.
      The Original Code is RabbitMQ.
 
      The Initial Developer of the Original Code is VMware, Inc.
-     Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.''
+     Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.''
 
      [NOTE: The text of this Exhibit A may differ slightly from the text of
      the notices in the Source Code files of the Original Code. You should
diff --git a/Makefile b/Makefile
index d46b4348..49bf926a 100644
--- a/Makefile
+++ b/Makefile
@@ -17,7 +17,7 @@ BEAM_TARGETS=$(patsubst $(SOURCE_DIR)/%.erl, $(EBIN_DIR)/%.beam, $(SOURCES))
 TARGETS=$(EBIN_DIR)/rabbit.app $(INCLUDE_DIR)/rabbit_framing.hrl $(BEAM_TARGETS) plugins
 WEB_URL=http://www.rabbitmq.com/
 MANPAGES=$(patsubst %.xml, %.gz, $(wildcard $(DOCS_DIR)/*.[0-9].xml))
-WEB_MANPAGES=$(patsubst %.xml, %.man.xml, $(wildcard $(DOCS_DIR)/*.[0-9].xml) $(DOCS_DIR)/rabbitmq-service.xml)
+WEB_MANPAGES=$(patsubst %.xml, %.man.xml, $(wildcard $(DOCS_DIR)/*.[0-9].xml) $(DOCS_DIR)/rabbitmq-service.xml $(DOCS_DIR)/rabbitmq-echopid.xml)
 USAGES_XML=$(DOCS_DIR)/rabbitmqctl.1.xml $(DOCS_DIR)/rabbitmq-plugins.1.xml
 USAGES_ERL=$(foreach XML, $(USAGES_XML), $(call usage_xml_to_erl, $(XML)))
 QC_MODULES := rabbit_backing_queue_qc
@@ -42,9 +42,9 @@ BASIC_PLT=basic.plt
 RABBIT_PLT=rabbit.plt
 
 ifndef USE_SPECS
-# our type specs rely on features and bug fixes in dialyzer that are
-# only available in R14B03 upwards (R14B03 is erts 5.8.4)
-USE_SPECS:=$(shell erl -noshell -eval 'io:format([list_to_integer(X) || X <- string:tokens(erlang:system_info(version), ".")] >= [5,8,4]), halt().')
+# our type specs rely on callback specs, which are available in R15B
+# upwards.
+USE_SPECS:=$(shell erl -noshell -eval 'io:format([list_to_integer(X) || X <- string:tokens(erlang:system_info(version), ".")] >= [5,9]), halt().')
 endif
 
 ifndef USE_PROPER_QC
@@ -56,7 +56,7 @@ endif
 #other args: +native +"{hipe,[o3,verbose]}" -Ddebug=true +debug_info +no_strict_record_tests
 ERLC_OPTS=-I $(INCLUDE_DIR) -o $(EBIN_DIR) -Wall -v +debug_info $(call boolean_macro,$(USE_SPECS),use_specs) $(call boolean_macro,$(USE_PROPER_QC),use_proper_qc)
 
-VERSION=0.0.0
+VERSION?=0.0.0
 PLUGINS_SRC_DIR?=$(shell [ -d "plugins-src" ] && echo "plugins-src" || echo )
 PLUGINS_DIR=plugins
 TARBALL_NAME=rabbitmq-server-$(VERSION)
@@ -207,7 +207,7 @@ start-background-node: all
 	-rm -f $(RABBITMQ_MNESIA_DIR).pid
 	mkdir -p $(RABBITMQ_MNESIA_DIR)
 	setsid sh -c "$(MAKE) run-background-node > $(RABBITMQ_MNESIA_DIR)/startup_log 2> $(RABBITMQ_MNESIA_DIR)/startup_err" &
-	sleep 1
+	./scripts/rabbitmqctl -n $(RABBITMQ_NODENAME) wait $(RABBITMQ_MNESIA_DIR).pid kernel
 
 start-rabbit-on-node: all
 	echo "rabbit:start()." | $(ERL_CALL)
@@ -216,12 +216,12 @@ start-rabbit-on-node: all
 stop-rabbit-on-node: all
 	echo "rabbit:stop()." | $(ERL_CALL)
 
-set-memory-alarm: all
-	echo "alarm_handler:set_alarm({{vm_memory_high_watermark, node()}, []})." | \
+set-resource-alarm: all
+	echo "alarm_handler:set_alarm({{resource_limit, $(SOURCE), node()}, []})." | \
 	$(ERL_CALL)
 
-clear-memory-alarm: all
-	echo "alarm_handler:clear_alarm({vm_memory_high_watermark, node()})." | \
+clear-resource-alarm: all
+	echo "alarm_handler:clear_alarm({resource_limit, $(SOURCE), node()})." | \
 	$(ERL_CALL)
 
 stop-node:
@@ -246,7 +246,8 @@ stop-cover: all
 srcdist: distclean
 	mkdir -p $(TARGET_SRC_DIR)/codegen
 	cp -r ebin src include LICENSE LICENSE-MPL-RabbitMQ INSTALL README $(TARGET_SRC_DIR)
-	sed -i.save 's/%%VSN%%/$(VERSION)/' $(TARGET_SRC_DIR)/ebin/rabbit_app.in && rm -f $(TARGET_SRC_DIR)/ebin/rabbit_app.in.save
+	sed 's/%%VSN%%/$(VERSION)/' $(TARGET_SRC_DIR)/ebin/rabbit_app.in > $(TARGET_SRC_DIR)/ebin/rabbit_app.in.tmp && \
+		mv $(TARGET_SRC_DIR)/ebin/rabbit_app.in.tmp $(TARGET_SRC_DIR)/ebin/rabbit_app.in
 
 	cp -r $(AMQP_CODEGEN_DIR)/* $(TARGET_SRC_DIR)/codegen/
 	cp codegen.py Makefile generate_app generate_deps calculate-relative $(TARGET_SRC_DIR)
@@ -315,7 +316,7 @@ install_bin: all install_dirs
 	cp -r ebin include LICENSE* INSTALL $(TARGET_DIR)
 
 	chmod 0755 scripts/*
-	for script in rabbitmq-env rabbitmq-server rabbitmqctl rabbitmq-plugins; do \
+	for script in rabbitmq-env rabbitmq-server rabbitmqctl rabbitmq-plugins rabbitmq-defaults; do \
 		cp scripts/$$script $(TARGET_DIR)/sbin; \
 		[ -e $(SBIN_DIR)/$$script ] || ln -s $(SCRIPTS_REL_PATH)/$$script $(SBIN_DIR)/$$script; \
 	done
@@ -346,10 +347,10 @@ $(foreach XML,$(USAGES_XML),$(eval $(call usage_dep, $(XML))))
 # Note that all targets which depend on clean must have clean in their
 # name.  Also any target that doesn't depend on clean should not have
 # clean in its name, unless you know that you don't need any of the
-# automatic dependency generation for that target (eg cleandb).
+# automatic dependency generation for that target (e.g. cleandb).
 
 # We want to load the dep file if *any* target *doesn't* contain
-# "clean" - i.e. if removing all clean-like targets leaves something
+# "clean" - i.e. if removing all clean-like targets leaves something.
 
 ifeq "$(MAKECMDGOALS)" ""
 TESTABLEGOALS:=$(.DEFAULT_GOAL)
diff --git a/codegen.py b/codegen.py
index 494be73d..9483e854 100644
--- a/codegen.py
+++ b/codegen.py
@@ -11,7 +11,7 @@
 ##  The Original Code is RabbitMQ.
 ##
 ##  The Initial Developer of the Original Code is VMware, Inc.
-##  Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+##  Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 ##
 
 from __future__ import nested_scopes
@@ -118,7 +118,7 @@ def printFileHeader():
 %%  The Original Code is RabbitMQ.
 %%
 %%  The Initial Developer of the Original Code is VMware, Inc.
-%%  Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%%  Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%"""
 
 def genErl(spec):
diff --git a/docs/html-to-website-xml.xsl b/docs/html-to-website-xml.xsl
index 88aa2e78..d83d5073 100644
--- a/docs/html-to-website-xml.xsl
+++ b/docs/html-to-website-xml.xsl
@@ -8,8 +8,6 @@
 
 <xsl:output method="xml" />
 
-<xsl:template match="*"/>
-
 <!-- Copy every element through -->
 <xsl:template match="*">
   <xsl:element name="{name()}" namespace="http://www.w3.org/1999/xhtml">
@@ -28,36 +26,30 @@
   <head>
     <title><xsl:value-of select="document($original)/refentry/refnamediv/refname"/><xsl:if test="document($original)/refentry/refmeta/manvolnum">(<xsl:value-of select="document($original)/refentry/refmeta/manvolnum"/>)</xsl:if> manual page</title>
   </head>
-  <body>
-    <doc:div>
-      <xsl:choose>
+  <body show-in-this-page="true">
+    <xsl:choose>
       <xsl:when test="document($original)/refentry/refmeta/manvolnum">
-      <p>
-        This is the manual page for
-        <code><xsl:value-of select="document($original)/refentry/refnamediv/refname"/>(<xsl:value-of select="document($original)/refentry/refmeta/manvolnum"/>)</code>.
-      </p>
-      <p>
-        <a href="../manpages.html">See a list of all manual pages</a>.
-      </p>
+        <p>
+          This is the manual page for
+          <code><xsl:value-of select="document($original)/refentry/refnamediv/refname"/>(<xsl:value-of select="document($original)/refentry/refmeta/manvolnum"/>)</code>.
+        </p>
+        <p>
+          <a href="../manpages.html">See a list of all manual pages</a>.
+        </p>
       </xsl:when>
       <xsl:otherwise>
-      <p>
-        This is the documentation for
-        <code><xsl:value-of select="document($original)/refentry/refnamediv/refname"/></code>.
-      </p>
+        <p>
+          This is the documentation for
+          <code><xsl:value-of select="document($original)/refentry/refnamediv/refname"/></code>.
+        </p>
       </xsl:otherwise>
-      </xsl:choose>
-      <p>
+    </xsl:choose>
+    <p>
          For more general documentation, please see the
-        <a href="../admin-guide.html">administrator's guide</a>.
-      </p>
-
-      <doc:toc class="compact">
-        <doc:heading>Table of Contents</doc:heading>
-      </doc:toc>
+         <a href="../admin-guide.html">administrator's guide</a>.
+    </p>
 
-      <xsl:apply-templates select="body/div[@class='refentry']"/>
-    </doc:div>
+    <xsl:apply-templates select="body/div[@class='refentry']"/>
   </body>
 </html>
 </xsl:template>
diff --git a/docs/rabbitmq-echopid.xml b/docs/rabbitmq-echopid.xml
new file mode 100644
index 00000000..d3dcea52
--- /dev/null
+++ b/docs/rabbitmq-echopid.xml
@@ -0,0 +1,71 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.docbook.org/xml/4.5/docbookx.dtd">
+<refentry lang="en">
+    <refentryinfo>
+        <productname>RabbitMQ Server</productname>
+        <authorgroup>
+            <corpauthor>The RabbitMQ Team &lt;<ulink url="mailto:info@rabbitmq.com"><email>info@rabbitmq.com</email></ulink>&gt;</corpauthor>
+        </authorgroup>
+    </refentryinfo>
+
+    <refmeta>
+        <refentrytitle>rabbitmq-echopid.bat</refentrytitle>
+        <refmiscinfo class="manual">RabbitMQ Server</refmiscinfo>
+    </refmeta>
+
+    <refnamediv>
+        <refname>rabbitmq-echopid.bat</refname>
+        <refpurpose>return the process id of the Erlang runtime hosting RabbitMQ</refpurpose>
+    </refnamediv>
+
+    <refsynopsisdiv>
+        <cmdsynopsis>
+          <command>rabbitmq-echopid.bat</command>
+          <arg choice="req">sname</arg>
+        </cmdsynopsis>
+    </refsynopsisdiv>
+
+    <refsect1>
+        <title>Description</title>
+        <para>
+           RabbitMQ is an implementation of AMQP, the emerging
+           standard for high performance enterprise messaging. The
+           RabbitMQ server is a robust and scalable implementation of
+           an AMQP broker.
+        </para>
+        <para>
+          Running <command>rabbitmq-echopid</command> will attempt to
+          discover and echo the process id (PID) of the Erlang runtime
+          process (erl.exe) that is hosting RabbitMQ. To allow erl.exe
+          time to start up and load RabbitMQ, the script will wait for
+          ten seconds before timing out if a suitable PID cannot be
+          found.
+        </para>
+        <para>
+          If a PID is discovered, the script will echo it to stdout
+          before exiting with a ERRORLEVEL of 0. If no PID is
+          discovered before the timeout, nothing is written to stdout
+          and the script exits setting ERRORLEVEL to 1.
+        </para>
+        <para>
+          Note that this script only exists on Windows due to the need
+          to wait for erl.exe and possibly time-out. To obtain the PID
+          on Unix set RABBITMQ_PID_FILE before starting
+          rabbitmq-server and do not use "-detached".
+        </para>
+    </refsect1>
+
+    <refsect1>
+      <title>Options</title>
+      <variablelist>
+        <varlistentry>
+          <term><cmdsynopsis><arg choice="req">sname</arg></cmdsynopsis></term>
+          <listitem>
+            <para role="usage">
+The short-name form of the RabbitMQ node name.
+            </para>
+          </listitem>
+        </varlistentry>
+      </variablelist>
+    </refsect1>
+</refentry>
diff --git a/docs/rabbitmqctl.1.xml b/docs/rabbitmqctl.1.xml
index 15755038..d6f6d51f 100644
--- a/docs/rabbitmqctl.1.xml
+++ b/docs/rabbitmqctl.1.xml
@@ -266,10 +266,9 @@
             </para>
             <para>
               When the target files do not exist they are created.
-              target files do not already exist.  When
-              no <option>suffix</option> is specified, the empty log
-              files are simply created at the original location; no
-              rotation takes place.
+              When no <option>suffix</option> is specified, the empty
+              log files are simply created at the original location;
+              no rotation takes place.
             </para>
             <para role="example-prefix">For example:</para>
             <screen role="example">rabbitmqctl rotate_logs .1</screen>
@@ -721,7 +720,7 @@
         </varlistentry>
 
         <varlistentry>
-          <term><cmdsynopsis><command>list_user_permissions</command> <arg choice="opt">-p <replaceable>vhostpath</replaceable></arg> <arg choice="req"><replaceable>username</replaceable></arg></cmdsynopsis></term>
+          <term><cmdsynopsis><command>list_user_permissions</command> <arg choice="req"><replaceable>username</replaceable></arg></cmdsynopsis></term>
           <listitem>
             <variablelist>
               <varlistentry>
@@ -746,6 +745,99 @@
     </refsect2>
 
     <refsect2>
+      <title>Parameter Management</title>
+      <para>
+        Certain features of RabbitMQ (such as the federation plugin)
+        are controlled by dynamic,
+        cluster-wide <emphasis>parameters</emphasis>. Each parameter
+        consists of a component name, a key and a value. The
+        component name and key are strings, and the value is an
+        Erlang term. Parameters can be set, cleared and listed. In
+        general you should refer to the documentation for the feature
+        in question to see how to set parameters.
+      </para>
+      <variablelist>
+        <varlistentry>
+          <term><cmdsynopsis><command>set_parameter</command> <arg choice="req"><replaceable>component_name</replaceable></arg> <arg choice="req"><replaceable>key</replaceable></arg> <arg choice="req"><replaceable>value</replaceable></arg></cmdsynopsis></term>
+          <listitem>
+            <para>
+              Sets a parameter.
+            </para>
+            <variablelist>
+              <varlistentry>
+                <term>component_name</term>
+                <listitem><para>
+                    The name of the component for which the
+                    parameter is being set.
+                </para></listitem>
+              </varlistentry>
+              <varlistentry>
+                <term>key</term>
+                <listitem><para>
+                    The key for which the parameter is being set.
+                </para></listitem>
+              </varlistentry>
+              <varlistentry>
+                <term>value</term>
+                <listitem><para>
+                    The value for the parameter, as an
+                    Erlang term. In most shells you are very likely to
+                    need to quote this.
+                </para></listitem>
+              </varlistentry>
+            </variablelist>
+            <para role="example-prefix">For example:</para>
+            <screen role="example">rabbitmqctl set_parameter federation local_username '&lt;&lt;"guest">>'</screen>
+            <para role="example">
+              This command sets the parameter <command>local_username</command> for the <command>federation</command> component to the Erlang term <command>&lt;&lt;"guest">></command>.
+            </para>
+          </listitem>
+        </varlistentry>
+        <varlistentry>
+          <term><cmdsynopsis><command>clear_parameter</command> <arg choice="req"><replaceable>component_name</replaceable></arg> <arg choice="req"><replaceable>key</replaceable></arg></cmdsynopsis></term>
+          <listitem>
+            <para>
+              Clears a parameter.
+            </para>
+            <variablelist>
+              <varlistentry>
+                <term>component_name</term>
+                <listitem><para>
+                    The name of the component for which the
+                    parameter is being cleared.
+                </para></listitem>
+              </varlistentry>
+              <varlistentry>
+                <term>key</term>
+                <listitem><para>
+                    The key for which the parameter is being cleared.
+                </para></listitem>
+              </varlistentry>
+            </variablelist>
+            <para role="example-prefix">For example:</para>
+            <screen role="example">rabbitmqctl clear_parameter federation local_username</screen>
+            <para role="example">
+              This command clears the parameter <command>local_username</command> for the <command>federation</command> component.
+            </para>
+          </listitem>
+        </varlistentry>
+        <varlistentry>
+          <term><cmdsynopsis><command>list_parameters</command></cmdsynopsis></term>
+          <listitem>
+            <para>
+              Lists all parameters.
+            </para>
+            <para role="example-prefix">For example:</para>
+            <screen role="example">rabbitmqctl list_parameters</screen>
+            <para role="example">
+              This command lists all parameters.
+            </para>
+          </listitem>
+        </varlistentry>
+      </variablelist>
+    </refsect2>
+
+    <refsect2>
       <title>Server Status</title>
       <para>
         The server status queries interrogate the server and return a list of
@@ -886,7 +978,8 @@
               </varlistentry>
               <varlistentry>
                 <term>type</term>
-                <listitem><para>The exchange type (one of [<command>direct</command>,
+                <listitem><para>The exchange type (such as
+                [<command>direct</command>,
                   <command>topic</command>, <command>headers</command>,
                   <command>fanout</command>]).</para></listitem>
               </varlistentry>
@@ -949,7 +1042,7 @@
                 <term>source_kind</term>
                 <listitem><para>The kind of the source of messages to
                 which the binding is attached. Currently always
-                queue. With non-ASCII characters escaped as in
+                exchange. With non-ASCII characters escaped as in
                 C.</para></listitem>
               </varlistentry>
               <varlistentry>
@@ -1012,6 +1105,10 @@
                 <listitem><para>Id of the Erlang process associated with the connection.</para></listitem>
               </varlistentry>
               <varlistentry>
+                <term>name</term>
+                <listitem><para>Readable name for the connection.</para></listitem>
+              </varlistentry>
+              <varlistentry>
                 <term>address</term>
                 <listitem><para>Server IP address.</para></listitem>
               </varlistentry>
@@ -1067,10 +1164,26 @@
                 <listitem><para>The period for which the peer's SSL
                 certificate is valid.</para></listitem>
               </varlistentry>
+
+              <varlistentry>
+                <term>last_blocked_by</term>
+                <listitem><para>The reason for which this connection
+                    was last blocked. One of 'resource' - due to a memory
+                    or disk alarm, 'flow' - due to internal flow control, or
+                    'none' if the connection was never
+                    blocked.</para></listitem>
+              </varlistentry>
+              <varlistentry>
+                <term>last_blocked_age</term>
+                <listitem><para>Time, in seconds, since this
+                    connection was last blocked, or
+                    'infinity'.</para></listitem>
+              </varlistentry>
+
               <varlistentry>
                 <term>state</term>
                 <listitem><para>Connection state (one of [<command>starting</command>, <command>tuning</command>,
-                  <command>opening</command>, <command>running</command>, <command>closing</command>, <command>closed</command>]).</para></listitem>
+                  <command>opening</command>, <command>running</command>, <command>blocking</command>, <command>blocked</command>, <command>closing</command>, <command>closed</command>]).</para></listitem>
               </varlistentry>
               <varlistentry>
                 <term>channels</term>
@@ -1127,8 +1240,9 @@
               </varlistentry>
             </variablelist>
             <para>
-              If no <command>connectioninfoitem</command>s are specified then  user, peer
-              address, peer port and connection state are displayed.
+              If no <command>connectioninfoitem</command>s are
+              specified then user, peer address, peer port, time since
+              flow control and memory block state are displayed.
             </para>
 
             <para role="example-prefix">
@@ -1171,6 +1285,10 @@
                   to which the channel belongs.</para></listitem>
               </varlistentry>
               <varlistentry>
+                <term>name</term>
+                <listitem><para>Readable name for the channel.</para></listitem>
+              </varlistentry>
+              <varlistentry>
                 <term>number</term>
                 <listitem><para>The number of the channel, which uniquely identifies it within
                   a connection.</para></listitem>
@@ -1273,9 +1391,10 @@
             <para>
               Displays broker status information such as the running
               applications on the current Erlang node, RabbitMQ and
-              Erlang versions, OS name and memory statistics. (See
-              the <command>cluster_status</command> command to find
-              out which nodes are clustered and running.)
+              Erlang versions, OS name, memory and file descriptor
+              statistics. (See the <command>cluster_status</command>
+              command to find out which nodes are clustered and
+              running.)
             </para>
             <para role="example-prefix">For example:</para>
             <screen role="example">rabbitmqctl status</screen>
@@ -1403,8 +1522,11 @@
             <variablelist>
               <varlistentry>
                 <term>fraction</term>
-                <listitem><para>The new memory threshhold fraction at which flow control is triggered, as a
-                                floating point number between 0.0 and 1.0 with a mandatory fractional part.</para></listitem>
+                <listitem><para>
+                    The new memory threshold fraction at which flow
+                    control is triggered, as a floating point number
+                    greater than or equal to 0.
+                </para></listitem>
               </varlistentry>
             </variablelist>
           </listitem>
diff --git a/ebin/rabbit_app.in b/ebin/rabbit_app.in
index 5ead1051..b7d14f20 100644
--- a/ebin/rabbit_app.in
+++ b/ebin/rabbit_app.in
@@ -19,6 +19,7 @@
          {ssl_listeners, []},
          {ssl_options, []},
          {vm_memory_high_watermark, 0.4},
+         {disk_free_limit, {mem_relative, 1.0}},
          {msg_store_index_module, rabbit_msg_store_ets_index},
          {backing_queue_module, rabbit_variable_queue},
          {frame_max, 131072},
@@ -37,10 +38,13 @@
          {auth_backends, [rabbit_auth_backend_internal]},
          {delegate_count, 16},
          {trace_vhosts, []},
+         {log_levels, [{connection, info}]},
+         {ssl_cert_login_from, distinguished_name},
          {tcp_listen_options, [binary,
                                {packet,        raw},
                                {reuseaddr,     true},
                                {backlog,       128},
                                {nodelay,       true},
+                               {linger,        {true, 0}},
                                {exit_on_close, false}]}
          ]}]}.
diff --git a/include/gm_specs.hrl b/include/gm_specs.hrl
index ee29706e..a317e63b 100644
--- a/include/gm_specs.hrl
+++ b/include/gm_specs.hrl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -ifdef(use_specs).
diff --git a/include/rabbit.hrl b/include/rabbit.hrl
index a603886c..5c73c8b8 100644
--- a/include/rabbit.hrl
+++ b/include/rabbit.hrl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -record(user, {username,
@@ -56,14 +56,18 @@
 -record(binding, {source, key, destination, args = []}).
 -record(reverse_binding, {destination, key, source, args = []}).
 
+-record(topic_trie_node, {trie_node, edge_count, binding_count}).
 -record(topic_trie_edge, {trie_edge, node_id}).
 -record(topic_trie_binding, {trie_binding, value = const}).
 
+-record(trie_node, {exchange_name, node_id}).
 -record(trie_edge, {exchange_name, node_id, word}).
 -record(trie_binding, {exchange_name, node_id, destination}).
 
 -record(listener, {node, protocol, host, ip_address, port}).
 
+-record(runtime_parameters, {key, value}).
+
 -record(basic_message, {exchange_name, routing_keys = [], content, id,
                         is_persistent}).
 
@@ -84,7 +88,7 @@
 
 %%----------------------------------------------------------------------------
 
--define(COPYRIGHT_MESSAGE, "Copyright (C) 2007-2011 VMware, Inc.").
+-define(COPYRIGHT_MESSAGE, "Copyright (C) 2007-2012 VMware, Inc.").
 -define(INFORMATION_MESSAGE, "Licensed under the MPL.  See http://www.rabbitmq.com/").
 -define(PROTOCOL_VERSION, "AMQP 0-9-1 / 0-9 / 0-8").
 -define(ERTS_MINIMUM, "5.6.3").
@@ -93,16 +97,7 @@
 
 -define(HIBERNATE_AFTER_MIN,        1000).
 -define(DESIRED_HIBERNATE,         10000).
+-define(CREDIT_DISC_BOUND,   {2000, 500}).
 
 -define(ROUTING_HEADERS, [<<"CC">>, <<"BCC">>]).
 -define(DELETED_HEADER, <<"BCC">>).
-
--ifdef(debug).
--define(LOGDEBUG0(F), rabbit_log:debug(F)).
--define(LOGDEBUG(F,A), rabbit_log:debug(F,A)).
--define(LOGMESSAGE(D,C,M,Co), rabbit_log:message(D,C,M,Co)).
--else.
--define(LOGDEBUG0(F), ok).
--define(LOGDEBUG(F,A), ok).
--define(LOGMESSAGE(D,C,M,Co), ok).
--endif.
diff --git a/include/rabbit_auth_backend_spec.hrl b/include/rabbit_auth_backend_spec.hrl
deleted file mode 100644
index 803bb75c..00000000
--- a/include/rabbit_auth_backend_spec.hrl
+++ /dev/null
@@ -1,31 +0,0 @@
-%% The contents of this file are subject to the Mozilla Public License
-%% Version 1.1 (the "License"); you may not use this file except in
-%% compliance with the License. You may obtain a copy of the License
-%% at http://www.mozilla.org/MPL/
-%%
-%% Software distributed under the License is distributed on an "AS IS"
-%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
-%% the License for the specific language governing rights and
-%% limitations under the License.
-%%
-%% The Original Code is RabbitMQ.
-%%
-%% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
-%%
-
--ifdef(use_specs).
-
--spec(description/0 :: () -> [{atom(), any()}]).
-
--spec(check_user_login/2 :: (rabbit_types:username(), [term()]) ->
-                                 {'ok', rabbit_types:user()} |
-                                 {'refused', string(), [any()]} |
-                                 {'error', any()}).
--spec(check_vhost_access/2 :: (rabbit_types:user(), rabbit_types:vhost()) ->
-                                   boolean() | {'error', any()}).
--spec(check_resource_access/3 :: (rabbit_types:user(),
-                                  rabbit_types:r(atom()),
-                                  rabbit_access_control:permission_atom()) ->
-                                      boolean() | {'error', any()}).
--endif.
diff --git a/include/rabbit_auth_mechanism_spec.hrl b/include/rabbit_auth_mechanism_spec.hrl
deleted file mode 100644
index 614a3eed..00000000
--- a/include/rabbit_auth_mechanism_spec.hrl
+++ /dev/null
@@ -1,28 +0,0 @@
-%% The contents of this file are subject to the Mozilla Public License
-%% Version 1.1 (the "License"); you may not use this file except in
-%% compliance with the License. You may obtain a copy of the License
-%% at http://www.mozilla.org/MPL/
-%%
-%% Software distributed under the License is distributed on an "AS IS"
-%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
-%% the License for the specific language governing rights and
-%% limitations under the License.
-%%
-%% The Original Code is RabbitMQ.
-%%
-%% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
-%%
-
--ifdef(use_specs).
-
--spec(description/0 :: () -> [{atom(), any()}]).
--spec(should_offer/1 :: (rabbit_net:socket()) -> boolean()).
--spec(init/1 :: (rabbit_net:socket()) -> any()).
--spec(handle_response/2 :: (binary(), any()) ->
-                                {'ok', rabbit_types:user()} |
-                                {'challenge', binary(), any()} |
-                                {'protocol_error', string(), [any()]} |
-                                {'refused', string(), [any()]}).
-
--endif.
diff --git a/include/rabbit_backing_queue_spec.hrl b/include/rabbit_backing_queue_spec.hrl
deleted file mode 100644
index 4a657951..00000000
--- a/include/rabbit_backing_queue_spec.hrl
+++ /dev/null
@@ -1,66 +0,0 @@
-%% The contents of this file are subject to the Mozilla Public License
-%% Version 1.1 (the "License"); you may not use this file except in
-%% compliance with the License. You may obtain a copy of the License
-%% at http://www.mozilla.org/MPL/
-%%
-%% Software distributed under the License is distributed on an "AS IS"
-%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
-%% the License for the specific language governing rights and
-%% limitations under the License.
-%%
-%% The Original Code is RabbitMQ.
-%%
-%% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
-%%
-
--type(fetch_result(Ack) ::
-        ('empty' |
-         %% Message,                  IsDelivered, AckTag, Remaining_Len
-         {rabbit_types:basic_message(), boolean(), Ack, non_neg_integer()})).
--type(is_durable() :: boolean()).
--type(attempt_recovery() :: boolean()).
--type(purged_msg_count() :: non_neg_integer()).
--type(confirm_required() :: boolean()).
--type(async_callback() :: fun ((atom(), fun ((atom(), state()) -> state())) -> 'ok')).
--type(duration() :: ('undefined' | 'infinity' | number())).
-
--spec(start/1 :: ([rabbit_amqqueue:name()]) -> 'ok').
--spec(stop/0 :: () -> 'ok').
--spec(init/3 :: (rabbit_types:amqqueue(), attempt_recovery(),
-                 async_callback()) -> state()).
--spec(terminate/2 :: (any(), state()) -> state()).
--spec(delete_and_terminate/2 :: (any(), state()) -> state()).
--spec(purge/1 :: (state()) -> {purged_msg_count(), state()}).
--spec(publish/4 :: (rabbit_types:basic_message(),
-                    rabbit_types:message_properties(), pid(), state()) ->
-                        state()).
--spec(publish_delivered/5 :: (true, rabbit_types:basic_message(),
-                              rabbit_types:message_properties(), pid(), state())
-                             -> {ack(), state()};
-                             (false, rabbit_types:basic_message(),
-                              rabbit_types:message_properties(), pid(), state())
-                             -> {undefined, state()}).
--spec(drain_confirmed/1 :: (state()) -> {[rabbit_guid:guid()], state()}).
--spec(dropwhile/2 ::
-        (fun ((rabbit_types:message_properties()) -> boolean()), state())
-        -> state()).
--spec(fetch/2 :: (true,  state()) -> {fetch_result(ack()), state()};
-                 (false, state()) -> {fetch_result(undefined), state()}).
--spec(ack/2 :: ([ack()], state()) -> {[rabbit_guid:guid()], state()}).
--spec(requeue/2 :: ([ack()], state())
-                   -> {[rabbit_guid:guid()], state()}).
--spec(len/1 :: (state()) -> non_neg_integer()).
--spec(is_empty/1 :: (state()) -> boolean()).
--spec(set_ram_duration_target/2 ::
-      (duration(), state()) -> state()).
--spec(ram_duration/1 :: (state()) -> {duration(), state()}).
--spec(needs_timeout/1 :: (state()) -> 'false' | 'timed' | 'idle').
--spec(timeout/1 :: (state()) -> state()).
--spec(handle_pre_hibernate/1 :: (state()) -> state()).
--spec(status/1 :: (state()) -> [{atom(), any()}]).
--spec(invoke/3 :: (atom(), fun ((atom(), A) -> A), state()) -> state()).
--spec(is_duplicate/2 ::
-        (rabbit_types:basic_message(), state()) ->
-                             {'false'|'published'|'discarded', state()}).
--spec(discard/3 :: (rabbit_types:basic_message(), pid(), state()) -> state()).
diff --git a/include/rabbit_exchange_type_spec.hrl b/include/rabbit_exchange_type_spec.hrl
deleted file mode 100644
index f6283ef7..00000000
--- a/include/rabbit_exchange_type_spec.hrl
+++ /dev/null
@@ -1,38 +0,0 @@
-%% The contents of this file are subject to the Mozilla Public License
-%% Version 1.1 (the "License"); you may not use this file except in
-%% compliance with the License. You may obtain a copy of the License
-%% at http://www.mozilla.org/MPL/
-%%
-%% Software distributed under the License is distributed on an "AS IS"
-%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
-%% the License for the specific language governing rights and
-%% limitations under the License.
-%%
-%% The Original Code is RabbitMQ.
-%%
-%% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
-%%
-
--ifdef(use_specs).
-
--type(tx() :: 'transaction' | 'none').
--type(serial() :: pos_integer() | tx()).
-
--spec(description/0 :: () -> [{atom(), any()}]).
--spec(serialise_events/0 :: () -> boolean()).
--spec(route/2 :: (rabbit_types:exchange(), rabbit_types:delivery())
-                 -> rabbit_router:match_result()).
--spec(validate/1 :: (rabbit_types:exchange()) -> 'ok').
--spec(create/2 :: (tx(), rabbit_types:exchange()) -> 'ok').
--spec(delete/3 :: (tx(), rabbit_types:exchange(),
-                   [rabbit_types:binding()]) -> 'ok').
--spec(add_binding/3 :: (serial(), rabbit_types:exchange(),
-                        rabbit_types:binding()) -> 'ok').
--spec(remove_bindings/3 :: (serial(), rabbit_types:exchange(),
-                            [rabbit_types:binding()]) -> 'ok').
--spec(assert_args_equivalence/2 ::
-        (rabbit_types:exchange(), rabbit_framing:amqp_table())
-        -> 'ok' | rabbit_types:connection_exit()).
-
--endif.
diff --git a/include/rabbit_msg_store.hrl b/include/rabbit_msg_store.hrl
index e9150a97..f7c10bd8 100644
--- a/include/rabbit_msg_store.hrl
+++ b/include/rabbit_msg_store.hrl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -include("rabbit.hrl").
diff --git a/include/rabbit_msg_store_index.hrl b/include/rabbit_msg_store_index.hrl
deleted file mode 100644
index 2ae5b000..00000000
--- a/include/rabbit_msg_store_index.hrl
+++ /dev/null
@@ -1,45 +0,0 @@
-%% The contents of this file are subject to the Mozilla Public License
-%% Version 1.1 (the "License"); you may not use this file except in
-%% compliance with the License. You may obtain a copy of the License
-%% at http://www.mozilla.org/MPL/
-%%
-%% Software distributed under the License is distributed on an "AS IS"
-%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
-%% the License for the specific language governing rights and
-%% limitations under the License.
-%%
-%% The Original Code is RabbitMQ.
-%%
-%% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
-%%
-
--include("rabbit_msg_store.hrl").
-
-%%----------------------------------------------------------------------------
-
--ifdef(use_specs).
-
--type(dir() :: any()).
--type(index_state() :: any()).
--type(keyvalue() :: any()).
--type(fieldpos() :: non_neg_integer()).
--type(fieldvalue() :: any()).
-
--spec(new/1 :: (dir()) -> index_state()).
--spec(recover/1 :: (dir()) -> rabbit_types:ok_or_error2(index_state(), any())).
--spec(lookup/2 ::
-        (rabbit_types:msg_id(), index_state()) -> ('not_found' | keyvalue())).
--spec(insert/2 :: (keyvalue(), index_state()) -> 'ok').
--spec(update/2 :: (keyvalue(), index_state()) -> 'ok').
--spec(update_fields/3 :: (rabbit_types:msg_id(), ({fieldpos(), fieldvalue()} |
-                                                  [{fieldpos(), fieldvalue()}]),
-                          index_state()) -> 'ok').
--spec(delete/2 :: (rabbit_types:msg_id(), index_state()) -> 'ok').
--spec(delete_object/2 :: (keyvalue(), index_state()) -> 'ok').
--spec(delete_by_file/2 :: (fieldvalue(), index_state()) -> 'ok').
--spec(terminate/1 :: (index_state()) -> any()).
-
--endif.
-
-%%----------------------------------------------------------------------------
diff --git a/packaging/RPMS/Fedora/Makefile b/packaging/RPMS/Fedora/Makefile
index c67d8fd6..180500ed 100644
--- a/packaging/RPMS/Fedora/Makefile
+++ b/packaging/RPMS/Fedora/Makefile
@@ -15,9 +15,11 @@ endif
 ifeq "$(RPM_OS)" "suse"
 REQUIRES=/sbin/chkconfig /sbin/service
 OS_DEFINES=--define '_initrddir /etc/init.d' --define 'dist .suse'
+START_PROG=setsid
 else
 REQUIRES=chkconfig initscripts
 OS_DEFINES=--define '_initrddir /etc/rc.d/init.d'
+START_PROG=runuser rabbitmq --session-command
 endif
 
 rpms:   clean server
@@ -30,8 +32,9 @@ prepare:
 		SPECS/rabbitmq-server.spec
 
 	cp ${COMMON_DIR}/* SOURCES/
+	cp rabbitmq-server.init SOURCES/rabbitmq-server.init
 	sed -i \
-	    -e 's|^LOCK_FILE=.*$$|LOCK_FILE=/var/lock/subsys/$$NAME|' \
+	    -e 's|^START_PROG=.*$$|START_PROG="$(START_PROG)"|' \
 	    SOURCES/rabbitmq-server.init
 ifeq "$(RPM_OS)" "fedora"
 # Fedora says that only vital services should have Default-Start
diff --git a/packaging/common/rabbitmq-server.init b/packaging/RPMS/Fedora/rabbitmq-server.init
index 4084d8c7..2d2680e3 100644
--- a/packaging/common/rabbitmq-server.init
+++ b/packaging/RPMS/Fedora/rabbitmq-server.init
@@ -26,7 +26,8 @@ ROTATE_SUFFIX=
 INIT_LOG_DIR=/var/log/rabbitmq
 PID_FILE=/var/run/rabbitmq/pid
 
-LOCK_FILE= # This is filled in when building packages
+START_PROG= # Set when building package
+LOCK_FILE=/var/lock/subsys/$NAME
 
 test -x $DAEMON || exit 0
 test -x $CONTROL || exit 0
@@ -34,6 +35,8 @@ test -x $CONTROL || exit 0
 RETVAL=0
 set -e
 
+[ -f /etc/default/${NAME} ] && . /etc/default/${NAME}
+
 ensure_pid_dir () {
     PID_DIR=`dirname ${PID_FILE}`
     if [ ! -d ${PID_DIR} ] ; then
@@ -56,7 +59,7 @@ start_rabbitmq () {
         RETVAL=0
         ensure_pid_dir
         set +e
-        RABBITMQ_PID_FILE=$PID_FILE setsid $DAEMON \
+        RABBITMQ_PID_FILE=$PID_FILE $START_PROG $DAEMON \
             > "${INIT_LOG_DIR}/startup_log" \
             2> "${INIT_LOG_DIR}/startup_err" \
             0<&- &
diff --git a/packaging/RPMS/Fedora/rabbitmq-server.spec b/packaging/RPMS/Fedora/rabbitmq-server.spec
index 96d3974f..a6899005 100644
--- a/packaging/RPMS/Fedora/rabbitmq-server.spec
+++ b/packaging/RPMS/Fedora/rabbitmq-server.spec
@@ -121,6 +121,9 @@ done
 rm -rf %{buildroot}
 
 %changelog
+* Fri Dec 16 2011 steve@rabbitmq.com 2.7.1-1
+- New Upstream Release
+
 * Tue Nov 8 2011 steve@rabbitmq.com 2.7.0-1
 - New Upstream Release
 
diff --git a/packaging/common/LICENSE.tail b/packaging/common/LICENSE.tail
index 5d842cc1..b9c2629b 100644
--- a/packaging/common/LICENSE.tail
+++ b/packaging/common/LICENSE.tail
@@ -56,7 +56,7 @@ The rest of this package is licensed under the Mozilla Public License 1.1
 Authors and Copyright are as described below:
 
      The Initial Developer of the Original Code is VMware, Inc.
-     Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+     Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 
 
                           MOZILLA PUBLIC LICENSE
@@ -508,7 +508,7 @@ EXHIBIT A -Mozilla Public License.
      The Original Code is RabbitMQ.
 
      The Initial Developer of the Original Code is VMware, Inc.
-     Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.''
+     Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.''
 
      [NOTE: The text of this Exhibit A may differ slightly from the text of
      the notices in the Source Code files of the Original Code. You should
diff --git a/packaging/common/rabbitmq-script-wrapper b/packaging/common/rabbitmq-script-wrapper
index 0436f546..0e59c218 100644
--- a/packaging/common/rabbitmq-script-wrapper
+++ b/packaging/common/rabbitmq-script-wrapper
@@ -12,7 +12,7 @@
 ##  The Original Code is RabbitMQ.
 ##
 ##  The Initial Developer of the Original Code is VMware, Inc.
-##  Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+##  Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 ##
 
 # Escape spaces and quotes, because shell is revolting.
diff --git a/packaging/common/rabbitmq-server.ocf b/packaging/common/rabbitmq-server.ocf
index e6776eff..14557286 100755
--- a/packaging/common/rabbitmq-server.ocf
+++ b/packaging/common/rabbitmq-server.ocf
@@ -12,7 +12,7 @@
 ##  The Original Code is RabbitMQ.
 ##
 ##  The Initial Developer of the Original Code is VMware, Inc.
-##  Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+##  Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 ##
 
 ##
diff --git a/packaging/debs/Debian/Makefile b/packaging/debs/Debian/Makefile
index 8696427e..844388c6 100644
--- a/packaging/debs/Debian/Makefile
+++ b/packaging/debs/Debian/Makefile
@@ -22,19 +22,12 @@ package: clean
 	tar -zxf $(DEBIAN_ORIG_TARBALL)
 	cp -r debian $(UNPACKED_DIR)
 	cp $(COMMON_DIR)/* $(UNPACKED_DIR)/debian/
-# Debian and descendants differ from most other distros in that
-# runlevel 2 should start network services.
-	sed -i \
-	    -e 's|^LOCK_FILE=.*$$|LOCK_FILE=|' \
-	    -e 's|^\(# Default-Start:\).*$$|\1 2 3 4 5|' \
-	    -e 's|^\(# Default-Stop:\).*$$|\1 0 1 6|' \
-	    $(UNPACKED_DIR)/debian/rabbitmq-server.init
 	sed -i -e 's|@SU_RABBITMQ_SH_C@|su rabbitmq -s /bin/sh -c|' \
 	    $(UNPACKED_DIR)/debian/rabbitmq-script-wrapper
 	chmod a+x $(UNPACKED_DIR)/debian/rules
 	echo "This package was debianized by Tony Garnock-Jones <tonyg@rabbitmq.com> on\nWed,  3 Jan 2007 15:43:44 +0000.\n\nIt was downloaded from http://www.rabbitmq.com/\n\n" > $(UNPACKED_DIR)/debian/copyright
 	cat $(UNPACKED_DIR)/LICENSE >> $(UNPACKED_DIR)/debian/copyright
-	echo "\n\nThe Debian packaging is (C) 2007-2011, VMware, Inc. and is licensed\nunder the MPL 1.1, see above.\n" >> $(UNPACKED_DIR)/debian/copyright
+	echo "\n\nThe Debian packaging is (C) 2007-2012, VMware, Inc. and is licensed\nunder the MPL 1.1, see above.\n" >> $(UNPACKED_DIR)/debian/copyright
 	UNOFFICIAL_RELEASE=$(UNOFFICIAL_RELEASE) VERSION=$(VERSION) ./check-changelog.sh rabbitmq-server $(UNPACKED_DIR)
 	cd $(UNPACKED_DIR); GNUPGHOME=$(GNUPG_PATH)/.gnupg dpkg-buildpackage -rfakeroot $(SIGNING)
 	rm -rf $(UNPACKED_DIR)
diff --git a/packaging/debs/Debian/debian/changelog b/packaging/debs/Debian/debian/changelog
index ceb08ed0..b3743c39 100644
--- a/packaging/debs/Debian/debian/changelog
+++ b/packaging/debs/Debian/debian/changelog
@@ -1,3 +1,9 @@
+rabbitmq-server (2.7.1-1) natty; urgency=low
+
+  * New Upstream Release
+
+ -- Steve Powell <steve@rabbitmq.com>  Fri, 16 Dec 2011 12:12:36 +0000
+
 rabbitmq-server (2.7.0-1) natty; urgency=low
 
   * New Upstream Release
diff --git a/packaging/debs/Debian/debian/control b/packaging/debs/Debian/debian/control
index 45f5c5c4..e935acf5 100644
--- a/packaging/debs/Debian/debian/control
+++ b/packaging/debs/Debian/debian/control
@@ -2,7 +2,9 @@ Source: rabbitmq-server
 Section: net
 Priority: extra
 Maintainer: RabbitMQ Team <packaging@rabbitmq.com>
-Build-Depends: cdbs, debhelper (>= 5), erlang-dev, python-simplejson, xmlto, xsltproc
+Uploader: Emile Joubert <emile@rabbitmq.com>
+DM-Upload-Allowed: yes
+Build-Depends: cdbs, debhelper (>= 5), erlang-dev, python-simplejson, xmlto, xsltproc, erlang-nox (>= 1:12.b.3), erlang-src (>= 1:12.b.3), unzip, zip
 Standards-Version: 3.8.0
 
 Package: rabbitmq-server
diff --git a/packaging/debs/Debian/debian/postrm.in b/packaging/debs/Debian/debian/postrm.in
index baf081fc..c2e9bbfe 100644
--- a/packaging/debs/Debian/debian/postrm.in
+++ b/packaging/debs/Debian/debian/postrm.in
@@ -35,20 +35,15 @@ case "$1" in
         if [ -d /etc/rabbitmq ]; then
                 rm -r /etc/rabbitmq
         fi
-	remove_plugin_traces
+        remove_plugin_traces
         if getent passwd rabbitmq >/dev/null; then
                 # Stop epmd if run by the rabbitmq user
                 pkill -u rabbitmq epmd || :
-
-                deluser rabbitmq
-        fi
-        if getent group rabbitmq >/dev/null; then
-                delgroup rabbitmq
         fi
     ;;
 
     remove|upgrade)
-	remove_plugin_traces
+        remove_plugin_traces
     ;;
 
     failed-upgrade|abort-install|abort-upgrade|disappear)
diff --git a/packaging/debs/Debian/debian/rabbitmq-server.default b/packaging/debs/Debian/debian/rabbitmq-server.default
new file mode 100644
index 00000000..bde5e308
--- /dev/null
+++ b/packaging/debs/Debian/debian/rabbitmq-server.default
@@ -0,0 +1,9 @@
+# This file is sourced by /etc/init.d/rabbitmq-server. Its primary
+# reason for existing is to allow adjustment of system limits for the
+# rabbitmq-server process.
+#
+# Maximum number of open file handles. This will need to be increased
+# to handle many simultaneous connections. Refer to the system
+# documentation for ulimit (in man bash) for more information.
+#
+#ulimit -n 1024
diff --git a/packaging/debs/Debian/debian/rabbitmq-server.init b/packaging/debs/Debian/debian/rabbitmq-server.init
new file mode 100644
index 00000000..f514b974
--- /dev/null
+++ b/packaging/debs/Debian/debian/rabbitmq-server.init
@@ -0,0 +1,185 @@
+#!/bin/sh
+#
+# rabbitmq-server RabbitMQ broker
+#
+# chkconfig: - 80 05
+# description: Enable AMQP service provided by RabbitMQ
+#
+
+### BEGIN INIT INFO
+# Provides:          rabbitmq-server
+# Required-Start:    $remote_fs $network
+# Required-Stop:     $remote_fs $network
+# Default-Start: 2 3 4 5
+# Default-Stop: 0 1 6
+# Description:       RabbitMQ broker
+# Short-Description: Enable AMQP service provided by RabbitMQ broker
+### END INIT INFO
+
+PATH=/sbin:/usr/sbin:/bin:/usr/bin
+NAME=rabbitmq-server
+DAEMON=/usr/sbin/${NAME}
+CONTROL=/usr/sbin/rabbitmqctl
+DESC="message broker"
+USER=rabbitmq
+ROTATE_SUFFIX=
+INIT_LOG_DIR=/var/log/rabbitmq
+PID_FILE=/var/run/rabbitmq/pid
+
+
+test -x $DAEMON || exit 0
+test -x $CONTROL || exit 0
+
+RETVAL=0
+set -e
+
+[ -f /etc/default/${NAME} ] && . /etc/default/${NAME}
+
+. /lib/lsb/init-functions
+. /lib/init/vars.sh
+
+ensure_pid_dir () {
+    PID_DIR=`dirname ${PID_FILE}`
+    if [ ! -d ${PID_DIR} ] ; then
+        mkdir -p ${PID_DIR}
+        chown -R ${USER}:${USER} ${PID_DIR}
+        chmod 755 ${PID_DIR}
+    fi
+}
+
+remove_pid () {
+    rm -f ${PID_FILE}
+    rmdir `dirname ${PID_FILE}` || :
+}
+
+start_rabbitmq () {
+    status_rabbitmq quiet
+    if [ $RETVAL != 0 ] ; then
+        RETVAL=0
+        ensure_pid_dir
+        set +e
+        RABBITMQ_PID_FILE=$PID_FILE start-stop-daemon --quiet \
+            --chuid rabbitmq --start --exec $DAEMON \
+            --pidfile "$RABBITMQ_PID_FILE" \
+            > "${INIT_LOG_DIR}/startup_log" \
+            2> "${INIT_LOG_DIR}/startup_err" \
+            0<&- &
+        $CONTROL wait $PID_FILE >/dev/null 2>&1
+        RETVAL=$?
+        set -e
+        if [ $RETVAL != 0 ] ; then
+            remove_pid
+        fi
+    else
+        RETVAL=3
+    fi
+}
+
+stop_rabbitmq () {
+    status_rabbitmq quiet
+    if [ $RETVAL = 0 ] ; then
+        set +e
+        $CONTROL stop ${PID_FILE} > ${INIT_LOG_DIR}/shutdown_log 2> ${INIT_LOG_DIR}/shutdown_err
+        RETVAL=$?
+        set -e
+        if [ $RETVAL = 0 ] ; then
+            remove_pid
+        fi
+    else
+        RETVAL=3
+    fi
+}
+
+status_rabbitmq() {
+    set +e
+    if [ "$1" != "quiet" ] ; then
+        $CONTROL status 2>&1
+    else
+        $CONTROL status > /dev/null 2>&1
+    fi
+    if [ $? != 0 ] ; then
+        RETVAL=3
+    fi
+    set -e
+}
+
+rotate_logs_rabbitmq() {
+    set +e
+    $CONTROL -q rotate_logs ${ROTATE_SUFFIX}
+    if [ $? != 0 ] ; then
+        RETVAL=1
+    fi
+    set -e
+}
+
+restart_running_rabbitmq () {
+    status_rabbitmq quiet
+    if [ $RETVAL = 0 ] ; then
+        restart_rabbitmq
+    else
+        log_warning_msg "${DESC} not running"
+    fi
+}
+
+restart_rabbitmq() {
+    stop_rabbitmq
+    start_rabbitmq
+}
+
+restart_end() {
+    if [ $RETVAL = 0 ] ; then
+        log_end_msg 0
+    else
+        log_end_msg 1
+    fi
+}
+
+start_stop_end() {
+    case "$RETVAL" in
+        0)
+            log_end_msg 0;;
+        3)
+            log_warning_msg "${DESC} already ${1}"
+            log_end_msg 0;;
+        *)
+            log_warning_msg "FAILED - check ${INIT_LOG_DIR}/startup_\{log, _err\}"
+            log_end_msg 1;;
+    esac
+}
+
+case "$1" in
+    start)
+        log_daemon_msg "Starting ${DESC}" $NAME
+        start_rabbitmq
+        start_stop_end "started"
+        ;;
+    stop)
+        log_daemon_msg "Stopping ${DESC}" $NAME
+        stop_rabbitmq
+        start_stop_end "stopped"
+        ;;
+    status)
+        status_rabbitmq
+        ;;
+    rotate-logs)
+        log_action_begin_msg "Rotating log files for ${DESC} ${NAME}"
+        rotate_logs_rabbitmq
+        log_action_end_msg $RETVAL
+        ;;
+    force-reload|reload|restart)
+        log_daemon_msg "Restarting ${DESC}" $NAME
+        restart_rabbitmq
+        restart_end
+        ;;
+    try-restart)
+        log_daemon_msg "Restarting ${DESC}" $NAME
+        restart_running_rabbitmq
+        restart_end
+        ;;
+    *)
+        echo "Usage: $0 {start|stop|status|rotate-logs|restart|condrestart|try-restart|reload|force-reload}" >&2
+        RETVAL=1
+        ;;
+esac
+
+exit $RETVAL
diff --git a/packaging/debs/Debian/debian/rules b/packaging/debs/Debian/debian/rules
index 108b1ed5..ecb778df 100644
--- a/packaging/debs/Debian/debian/rules
+++ b/packaging/debs/Debian/debian/rules
@@ -19,3 +19,4 @@ install/rabbitmq-server::
 	done
 	sed -e 's|@RABBIT_LIB@|/usr/lib/rabbitmq/lib/rabbitmq_server-$(DEB_UPSTREAM_VERSION)|g' <debian/postrm.in >debian/postrm
 	install -p -D -m 0755 debian/rabbitmq-server.ocf $(DEB_DESTDIR)usr/lib/ocf/resource.d/rabbitmq/rabbitmq-server
+	install -p -D -m 0644 debian/rabbitmq-server.default $(DEB_DESTDIR)etc/default/rabbitmq-server
diff --git a/packaging/debs/apt-repository/README-real-repository b/packaging/debs/apt-repository/README-real-repository
index b1526227..189852eb 100644
--- a/packaging/debs/apt-repository/README-real-repository
+++ b/packaging/debs/apt-repository/README-real-repository
@@ -13,7 +13,7 @@ that's a baby rabbit.
 
 Secondly, a note on software. We need a tool to manage the repository, 
 and a tool to perform uploads to the repository. Debian being Debian 
-there are quite a few of each. We will use "rerepro" to manage the 
+there are quite a few of each. We will use "reprepro" to manage the 
 repository since it's modern, maintained, and fairly simple. We will use 
 "dupload" to perform the uploads since it gives us the ability to run 
 arbitrary commands after the upload, which means we don't need to run a 
@@ -99,7 +99,7 @@ machine
 * "rm -rf" the uploads folder
 
 This is a bit cheesy but should be enough for our purposes. The 
-dupload.conf uses scp and ssh so you need a public-key login (or tpye 
+dupload.conf uses scp and ssh so you need a public-key login (or type 
 your password lots).
 
 There's still an open question as to whether dupload is really needed 
diff --git a/packaging/generic-unix/Makefile b/packaging/generic-unix/Makefile
index b5c342aa..b6ef9532 100644
--- a/packaging/generic-unix/Makefile
+++ b/packaging/generic-unix/Makefile
@@ -12,6 +12,13 @@ dist:
 		MAN_DIR=`pwd`/$(TARGET_DIR)/share/man \
 			install
 
+	sed -e 's:^SYS_PREFIX=$$:SYS_PREFIX=\$${RABBITMQ_HOME}:' \
+        $(TARGET_DIR)/sbin/rabbitmq-defaults >$(TARGET_DIR)/sbin/rabbitmq-defaults.tmp \
+        && mv $(TARGET_DIR)/sbin/rabbitmq-defaults.tmp $(TARGET_DIR)/sbin/rabbitmq-defaults
+	chmod 0755 $(TARGET_DIR)/sbin/rabbitmq-defaults
+
+	mkdir -p $(TARGET_DIR)/etc/rabbitmq
+
 	tar -zcf $(TARGET_TARBALL).tar.gz $(TARGET_DIR)
 	rm -rf $(SOURCE_DIR) $(TARGET_DIR)
 
diff --git a/packaging/macports/Makefile b/packaging/macports/Makefile
index 47da02dc..897fc183 100644
--- a/packaging/macports/Makefile
+++ b/packaging/macports/Makefile
@@ -38,9 +38,8 @@ $(DEST)/Portfile: Portfile.in
 # needs vars such as HOME to be set.  So we have to set them
 # explicitly.
 macports: dirs $(DEST)/Portfile
-	cp $(COMMON_DIR)/rabbitmq-script-wrapper $(DEST)/files
-	sed -i -e 's|@SU_RABBITMQ_SH_C@|SHELL=/bin/sh HOME=/var/lib/rabbitmq USER=rabbitmq LOGNAME=rabbitmq PATH="$$(eval `PATH=MACPORTS_PREFIX/bin /usr/libexec/path_helper -s`; echo $$PATH)" su -m rabbitmq -c|' \
-	    $(DEST)/files/rabbitmq-script-wrapper
+	sed -e 's|@SU_RABBITMQ_SH_C@|SHELL=/bin/sh HOME=/var/lib/rabbitmq USER=rabbitmq LOGNAME=rabbitmq PATH="$$(eval `PATH=@MACPORTS_PREFIX@/bin /usr/libexec/path_helper -s`; echo $$PATH)" su -m rabbitmq -c|' \
+		$(COMMON_DIR)/rabbitmq-script-wrapper >$(DEST)/files/rabbitmq-script-wrapper
 	cp patch-org.macports.rabbitmq-server.plist.diff $(DEST)/files
 	if [ -n "$(MACPORTS_USERHOST)" ] ; then \
 	  tar cf - -C $(MACPORTS_DIR) . | ssh $(SSH_OPTS) $(MACPORTS_USERHOST) ' \
diff --git a/packaging/macports/Portfile.in b/packaging/macports/Portfile.in
index b6dad357..e461e49e 100644
--- a/packaging/macports/Portfile.in
+++ b/packaging/macports/Portfile.in
@@ -48,6 +48,7 @@ set serveruser  rabbitmq
 set servergroup rabbitmq
 set serverhome ${prefix}/var/lib/rabbitmq
 set logdir ${prefix}/var/log/rabbitmq
+set confdir ${prefix}/etc/rabbitmq
 set mnesiadbdir ${prefix}/var/lib/rabbitmq/mnesia
 set plistloc ${prefix}/etc/LaunchDaemons/org.macports.rabbitmq-server
 set sbindir ${destroot}${prefix}/lib/rabbitmq/bin
@@ -60,6 +61,12 @@ use_configure   no
 
 use_parallel_build yes
 
+build.env-append HOME=${workpath}
+
+build.env-append VERSION=${version}
+
+destroot.env-append VERSION=${version}
+
 destroot.target install_bin
 
 destroot.destdir \
@@ -68,6 +75,7 @@ destroot.destdir \
     MAN_DIR=${destroot}${prefix}/share/man
 
 destroot.keepdirs \
+    ${destroot}${confdir} \
     ${destroot}${logdir} \
     ${destroot}${mnesiadbdir}
 
@@ -77,22 +85,19 @@ pre-destroot {
 }
 
 post-destroot {
+    xinstall -d -m 775 ${destroot}${confdir}
     xinstall -d -g [existsgroup ${servergroup}] -m 775 ${destroot}${logdir}
     xinstall -d -g [existsgroup ${servergroup}] -m 775 ${destroot}${serverhome}
     xinstall -d -g [existsgroup ${servergroup}] -m 775 ${destroot}${mnesiadbdir}
 
-    reinplace -E "s:(/etc/rabbitmq/rabbitmq):${prefix}\\1:g" \
-        ${realsbin}/rabbitmq-env
-    foreach var {CONFIG_FILE LOG_BASE MNESIA_BASE ENABLED_PLUGINS_FILE} {
-        reinplace -E "s:^($var)=/:\\1=${prefix}/:" \
-            ${realsbin}/rabbitmq-server \
-            ${realsbin}/rabbitmqctl \
-            ${realsbin}/rabbitmq-plugins
-    }
+    reinplace -E "s:^SYS_PREFIX=\${RABBITMQ_HOME}$:SYS_PREFIX=${prefix}:" \
+        ${realsbin}/rabbitmq-defaults
+    reinplace -E "s:^SYS_PREFIX=$:SYS_PREFIX=${prefix}:" \
+        ${realsbin}/rabbitmq-defaults
 
     xinstall -m 555 ${filespath}/rabbitmq-script-wrapper \
                 ${wrappersbin}/rabbitmq-server
-    reinplace -E "s:MACPORTS_PREFIX/bin:${prefix}/bin:g" \
+    reinplace -E "s:@MACPORTS_PREFIX@:${prefix}:g" \
                 ${wrappersbin}/rabbitmq-server
     reinplace -E "s:/usr/lib/rabbitmq/bin/:${prefix}/lib/rabbitmq/bin/:g" \
                 ${wrappersbin}/rabbitmq-server
diff --git a/packaging/windows-exe/rabbitmq_nsi.in b/packaging/windows-exe/rabbitmq_nsi.in
index 27e4e1dc..91510991 100644
--- a/packaging/windows-exe/rabbitmq_nsi.in
+++ b/packaging/windows-exe/rabbitmq_nsi.in
@@ -37,7 +37,7 @@ VIAddVersionKey /LANG=${LANG_ENGLISH} "ProductName" "RabbitMQ Server"
 ;VIAddVersionKey /LANG=${LANG_ENGLISH} "Comments" ""
 VIAddVersionKey /LANG=${LANG_ENGLISH} "CompanyName" "VMware, Inc"
 ;VIAddVersionKey /LANG=${LANG_ENGLISH} "LegalTrademarks" "" ; TODO ?
-VIAddVersionKey /LANG=${LANG_ENGLISH} "LegalCopyright" "Copyright (c) 2007-2011 VMware, Inc.  All rights reserved."
+VIAddVersionKey /LANG=${LANG_ENGLISH} "LegalCopyright" "Copyright (c) 2007-2012 VMware, Inc.  All rights reserved."
 VIAddVersionKey /LANG=${LANG_ENGLISH} "FileDescription" "RabbitMQ Server"
 VIAddVersionKey /LANG=${LANG_ENGLISH} "FileVersion" "%%VERSION%%"
 
diff --git a/packaging/windows/Makefile b/packaging/windows/Makefile
index 828cf000..1c222162 100644
--- a/packaging/windows/Makefile
+++ b/packaging/windows/Makefile
@@ -8,10 +8,7 @@ dist:
 	$(MAKE) -C $(SOURCE_DIR)
 
 	mkdir $(SOURCE_DIR)/sbin
-	mv $(SOURCE_DIR)/scripts/rabbitmq-server.bat $(SOURCE_DIR)/sbin
-	mv $(SOURCE_DIR)/scripts/rabbitmq-service.bat $(SOURCE_DIR)/sbin
-	mv $(SOURCE_DIR)/scripts/rabbitmq-plugins.bat $(SOURCE_DIR)/sbin
-	mv $(SOURCE_DIR)/scripts/rabbitmqctl.bat $(SOURCE_DIR)/sbin
+	mv $(SOURCE_DIR)/scripts/*.bat $(SOURCE_DIR)/sbin
 	rm -rf $(SOURCE_DIR)/scripts
 	rm -rf $(SOURCE_DIR)/codegen* $(SOURCE_DIR)/Makefile $(SOURCE_DIR)/*mk
 	rm -f $(SOURCE_DIR)/README
@@ -26,6 +23,9 @@ dist:
 	elinks -dump -no-references -no-numbering rabbitmq-service.html \
 		> $(TARGET_DIR)/readme-service.txt
 	todos $(TARGET_DIR)/readme-service.txt
+	todos $(TARGET_DIR)/INSTALL
+	todos $(TARGET_DIR)/LICENSE*
+	todos $(TARGET_DIR)/plugins/README.txt
 	rm -rf $(TARGET_DIR)/plugins-src
 	zip -q -r $(TARGET_ZIP).zip $(TARGET_DIR)
 	rm -rf $(TARGET_DIR) rabbitmq-service.html
diff --git a/scripts/rabbitmq-defaults b/scripts/rabbitmq-defaults
new file mode 100644
index 00000000..4763f086
--- /dev/null
+++ b/scripts/rabbitmq-defaults
@@ -0,0 +1,30 @@
+#!/bin/sh
+##  The contents of this file are subject to the Mozilla Public License
+##  Version 1.1 (the "License"); you may not use this file except in
+##  compliance with the License. You may obtain a copy of the License
+##  at http://www.mozilla.org/MPL/
+##
+##  Software distributed under the License is distributed on an "AS IS"
+##  basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+##  the License for the specific language governing rights and
+##  limitations under the License.
+##
+##  The Original Code is RabbitMQ.
+##
+##  The Initial Developer of the Original Code is VMware, Inc.
+##  Copyright (c) 2012 VMware, Inc.  All rights reserved.
+##
+
+### next line potentially updated in package install steps
+SYS_PREFIX=
+
+## Set default values
+
+CONFIG_FILE=${SYS_PREFIX}/etc/rabbitmq/rabbitmq
+LOG_BASE=${SYS_PREFIX}/var/log/rabbitmq
+MNESIA_BASE=${SYS_PREFIX}/var/lib/rabbitmq/mnesia
+ENABLED_PLUGINS_FILE=${SYS_PREFIX}/etc/rabbitmq/enabled_plugins
+
+PLUGINS_DIR="${RABBITMQ_HOME}/plugins"
+
+CONF_ENV_FILE=${SYS_PREFIX}/etc/rabbitmq/rabbitmq-env.conf
diff --git a/scripts/rabbitmq-echopid.bat b/scripts/rabbitmq-echopid.bat
new file mode 100644
index 00000000..5c652c30
--- /dev/null
+++ b/scripts/rabbitmq-echopid.bat
@@ -0,0 +1,49 @@
+@echo off
+
+REM Usage: rabbitmq-echopid.bat <rabbitmq_nodename>
+REM
+REM <rabbitmq_nodename> sname of the erlang node to connect to (required)
+
+setlocal
+
+if "%1"=="" goto fail
+
+:: set timeout vars ::
+set TIMEOUT=10
+set TIMER=1
+
+:: check that wmic exists ::
+set WMIC_PATH=%SYSTEMROOT%\System32\Wbem\wmic.exe
+if not exist "%WMIC_PATH%" (
+  goto fail
+)
+
+:getpid
+for /f "usebackq tokens=* skip=1" %%P IN (`%%WMIC_PATH%% process where "name='erl.exe' and commandline like '%%-sname %1%%'" get processid 2^>nul`) do (
+  set PID=%%P
+  goto echopid
+)
+
+:echopid
+:: check for pid not found ::
+if "%PID%" == "" (
+  PING 127.0.0.1 -n 2 > nul
+  set /a TIMER+=1
+  if %TIMEOUT%==%TIMER% goto fail
+  goto getpid
+)
+
+:: show pid ::
+echo %PID%
+
+:: all done ::
+:ok
+endlocal
+EXIT /B 0
+
+:: something went wrong ::
+:fail
+endlocal
+EXIT /B 1
+
+
diff --git a/scripts/rabbitmq-env b/scripts/rabbitmq-env
index a2ef8d3c..23224943 100755
--- a/scripts/rabbitmq-env
+++ b/scripts/rabbitmq-env
@@ -12,10 +12,11 @@
 ##  The Original Code is RabbitMQ.
 ##
 ##  The Initial Developer of the Original Code is VMware, Inc.
-##  Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+##  Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 ##
 
-# Determine where this script is really located
+# Determine where this script is really located (if this script is
+# invoked from another script, this is the location of the caller)
 SCRIPT_PATH="$0"
 while [ -h "$SCRIPT_PATH" ] ; do
     FULL_PATH=`readlink -f $SCRIPT_PATH 2>/dev/null`
@@ -36,10 +37,19 @@ RABBITMQ_HOME="${SCRIPT_DIR}/.."
 [ "x" = "x$HOSTNAME" ] && HOSTNAME=`env hostname`
 NODENAME=rabbit@${HOSTNAME%%.*}
 
-# Load configuration from the rabbitmq.conf file
+## Set defaults
+. ${SCRIPT_DIR}/rabbitmq-defaults
+
+## Common defaults
+SERVER_ERL_ARGS="+K true +A30 +P 1048576 \
+  -kernel inet_default_connect_options [{nodelay,true}]"
+
+# warn about old rabbitmq.conf file, if no new one
 if [ -f /etc/rabbitmq/rabbitmq.conf ] && \
-   [ ! -f /etc/rabbitmq/rabbitmq-env.conf ] ; then
+   [ ! -f ${CONF_ENV_FILE} ] ; then
     echo -n "WARNING: ignoring /etc/rabbitmq/rabbitmq.conf -- "
-    echo "location has moved to /etc/rabbitmq/rabbitmq-env.conf"
+    echo "location has moved to ${CONF_ENV_FILE}"
 fi
-[ -f /etc/rabbitmq/rabbitmq-env.conf ] && . /etc/rabbitmq/rabbitmq-env.conf
+
+## Get configuration variables from the configure environment file
+[ -f ${CONF_ENV_FILE} ] && . ${CONF_ENV_FILE}
diff --git a/scripts/rabbitmq-plugins b/scripts/rabbitmq-plugins
index 4c6cb1fa..14a18d57 100755
--- a/scripts/rabbitmq-plugins
+++ b/scripts/rabbitmq-plugins
@@ -12,16 +12,19 @@
 ##  The Original Code is RabbitMQ.
 ##
 ##  The Initial Developer of the Original Code is VMware, Inc.
-##  Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+##  Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 ##
 
+# Get default settings with user overrides for (RABBITMQ_)<var_name>
+# Non-empty defaults should be set in rabbitmq-env
 . `dirname $0`/rabbitmq-env
 
-ENABLED_PLUGINS_FILE=/etc/rabbitmq/enabled_plugins
+##--- Set environment vars RABBITMQ_<var_name> to defaults if not set
 
 [ "x" = "x$RABBITMQ_ENABLED_PLUGINS_FILE" ] && RABBITMQ_ENABLED_PLUGINS_FILE=${ENABLED_PLUGINS_FILE}
+[ "x" = "x$RABBITMQ_PLUGINS_DIR" ] && RABBITMQ_PLUGINS_DIR=${PLUGINS_DIR}
 
-[ "x" = "x$RABBITMQ_PLUGINS_DIR" ] && RABBITMQ_PLUGINS_DIR="${RABBITMQ_HOME}/plugins"
+##--- End of overridden <var_name> variables
 
 exec erl \
     -pa "${RABBITMQ_HOME}/ebin" \
diff --git a/scripts/rabbitmq-plugins.bat b/scripts/rabbitmq-plugins.bat
index ca874a7f..66a900a1 100755
--- a/scripts/rabbitmq-plugins.bat
+++ b/scripts/rabbitmq-plugins.bat
@@ -12,7 +12,7 @@ REM
 REM  The Original Code is RabbitMQ.

 REM

 REM  The Initial Developer of the Original Code is VMware, Inc.

-REM  Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.

+REM  Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.

 REM

 

 setlocal

diff --git a/scripts/rabbitmq-server b/scripts/rabbitmq-server
index 1831f876..0a5a4640 100755
--- a/scripts/rabbitmq-server
+++ b/scripts/rabbitmq-server
@@ -12,33 +12,23 @@
 ##  The Original Code is RabbitMQ.
 ##
 ##  The Initial Developer of the Original Code is VMware, Inc.
-##  Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+##  Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 ##
 
-SERVER_ERL_ARGS="+K true +A30 +P 1048576 \
--kernel inet_default_connect_options [{nodelay,true}]"
-CONFIG_FILE=/etc/rabbitmq/rabbitmq
-LOG_BASE=/var/log/rabbitmq
-MNESIA_BASE=/var/lib/rabbitmq/mnesia
-SERVER_START_ARGS=
-ENABLED_PLUGINS_FILE=/etc/rabbitmq/enabled_plugins
-
+# Get default settings with user overrides for (RABBITMQ_)<var_name>
+# Non-empty defaults should be set in rabbitmq-env
 . `dirname $0`/rabbitmq-env
 
+##--- Set environment vars RABBITMQ_<var_name> to defaults if not set
+
 DEFAULT_NODE_IP_ADDRESS=auto
 DEFAULT_NODE_PORT=5672
-[ "x" = "x$RABBITMQ_NODE_IP_ADDRESS" ] && [ "x" != "x$NODE_IP_ADDRESS" ] && RABBITMQ_NODE_IP_ADDRESS=${NODE_IP_ADDRESS}
-[ "x" = "x$RABBITMQ_NODE_PORT" ] && [ "x" != "x$NODE_PORT" ] && RABBITMQ_NODE_PORT=${NODE_PORT}
-if [ "x" = "x$RABBITMQ_NODE_IP_ADDRESS" ]
-then
-    if [ "x" != "x$RABBITMQ_NODE_PORT" ]
-    then RABBITMQ_NODE_IP_ADDRESS=${DEFAULT_NODE_IP_ADDRESS}
-    fi
-else
-    if [ "x" = "x$RABBITMQ_NODE_PORT" ]
-    then RABBITMQ_NODE_PORT=${DEFAULT_NODE_PORT}
-    fi
-fi
+[ "x" = "x$RABBITMQ_NODE_IP_ADDRESS" ] && RABBITMQ_NODE_IP_ADDRESS=${NODE_IP_ADDRESS}
+[ "x" = "x$RABBITMQ_NODE_PORT" ] && RABBITMQ_NODE_PORT=${NODE_PORT}
+
+[ "x" = "x$RABBITMQ_NODE_IP_ADDRESS" ] && [ "x" != "x$RABBITMQ_NODE_PORT" ] && RABBITMQ_NODE_IP_ADDRESS=${DEFAULT_NODE_IP_ADDRESS}
+[ "x" != "x$RABBITMQ_NODE_IP_ADDRESS" ] && [ "x" = "x$RABBITMQ_NODE_PORT" ] && RABBITMQ_NODE_PORT=${DEFAULT_NODE_PORT}
+
 [ "x" = "x$RABBITMQ_NODENAME" ] && RABBITMQ_NODENAME=${NODENAME}
 [ "x" = "x$RABBITMQ_SERVER_ERL_ARGS" ] && RABBITMQ_SERVER_ERL_ARGS=${SERVER_ERL_ARGS}
 [ "x" = "x$RABBITMQ_CONFIG_FILE" ] && RABBITMQ_CONFIG_FILE=${CONFIG_FILE}
@@ -48,13 +38,16 @@ fi
 
 [ "x" = "x$RABBITMQ_MNESIA_DIR" ] && RABBITMQ_MNESIA_DIR=${MNESIA_DIR}
 [ "x" = "x$RABBITMQ_MNESIA_DIR" ] && RABBITMQ_MNESIA_DIR=${RABBITMQ_MNESIA_BASE}/${RABBITMQ_NODENAME}
+
+[ "x" = "x$RABBITMQ_PID_FILE" ] && RABBITMQ_PID_FILE=${PID_FILE}
 [ "x" = "x$RABBITMQ_PID_FILE" ] && RABBITMQ_PID_FILE=${RABBITMQ_MNESIA_DIR}.pid
 
 [ "x" = "x$RABBITMQ_PLUGINS_EXPAND_DIR" ] && RABBITMQ_PLUGINS_EXPAND_DIR=${PLUGINS_EXPAND_DIR}
 [ "x" = "x$RABBITMQ_PLUGINS_EXPAND_DIR" ] && RABBITMQ_PLUGINS_EXPAND_DIR=${RABBITMQ_MNESIA_BASE}/${RABBITMQ_NODENAME}-plugins-expand
 
 [ "x" = "x$RABBITMQ_ENABLED_PLUGINS_FILE" ] && RABBITMQ_ENABLED_PLUGINS_FILE=${ENABLED_PLUGINS_FILE}
-[ "x" = "x$RABBITMQ_PLUGINS_DIR" ] && RABBITMQ_PLUGINS_DIR="${RABBITMQ_HOME}/plugins"
+
+[ "x" = "x$RABBITMQ_PLUGINS_DIR" ] && RABBITMQ_PLUGINS_DIR=${PLUGINS_DIR}
 
 ## Log rotation
 [ "x" = "x$RABBITMQ_LOGS" ] && RABBITMQ_LOGS=${LOGS}
@@ -62,6 +55,8 @@ fi
 [ "x" = "x$RABBITMQ_SASL_LOGS" ] && RABBITMQ_SASL_LOGS=${SASL_LOGS}
 [ "x" = "x$RABBITMQ_SASL_LOGS" ] && RABBITMQ_SASL_LOGS="${RABBITMQ_LOG_BASE}/${RABBITMQ_NODENAME}-sasl.log"
 
+##--- End of overridden <var_name> variables
+
 RABBITMQ_START_RABBIT=
 [ "x" = "x$RABBITMQ_ALLOW_INPUT" ] && RABBITMQ_START_RABBIT='-noinput'
 
@@ -117,7 +112,7 @@ exec erl \
     -sasl sasl_error_logger false \
     -rabbit error_logger '{file,"'${RABBITMQ_LOGS}'"}' \
     -rabbit sasl_error_logger '{file,"'${RABBITMQ_SASL_LOGS}'"}' \
-    -os_mon start_cpu_sup true \
+    -os_mon start_cpu_sup false \
     -os_mon start_disksup false \
     -os_mon start_memsup false \
     -mnesia dir "\"${RABBITMQ_MNESIA_DIR}\"" \
diff --git a/scripts/rabbitmq-server.bat b/scripts/rabbitmq-server.bat
index c27b418a..ca49a5d8 100755
--- a/scripts/rabbitmq-server.bat
+++ b/scripts/rabbitmq-server.bat
@@ -12,7 +12,7 @@ REM
 REM  The Original Code is RabbitMQ.

 REM

 REM  The Initial Developer of the Original Code is VMware, Inc.

-REM  Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.

+REM  Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.

 REM

 

 setlocal

@@ -139,7 +139,7 @@ if not "!RABBITMQ_NODE_IP_ADDRESS!"=="" (
 -sasl sasl_error_logger false ^

 -rabbit error_logger {file,\""!LOGS:\=/!"\"} ^

 -rabbit sasl_error_logger {file,\""!SASL_LOGS:\=/!"\"} ^

--os_mon start_cpu_sup true ^

+-os_mon start_cpu_sup false ^

 -os_mon start_disksup false ^

 -os_mon start_memsup false ^

 -mnesia dir \""!RABBITMQ_MNESIA_DIR:\=/!"\" ^

diff --git a/scripts/rabbitmq-service.bat b/scripts/rabbitmq-service.bat
index 4d3fce49..9e274840 100755
--- a/scripts/rabbitmq-service.bat
+++ b/scripts/rabbitmq-service.bat
@@ -12,7 +12,7 @@ REM
 REM  The Original Code is RabbitMQ.

 REM

 REM  The Initial Developer of the Original Code is VMware, Inc.

-REM  Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.

+REM  Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.

 REM

 

 setlocal

@@ -145,7 +145,7 @@ if not exist "!RABBITMQ_BASE!" (
 

 "!ERLANG_SERVICE_MANAGER_PATH!\erlsrv" list !RABBITMQ_SERVICENAME! 2>NUL 1>NUL

 if errorlevel 1 (

-    "!ERLANG_SERVICE_MANAGER_PATH!\erlsrv" add !RABBITMQ_SERVICENAME!

+    "!ERLANG_SERVICE_MANAGER_PATH!\erlsrv" add !RABBITMQ_SERVICENAME! -internalservicename !RABBITMQ_SERVICENAME!

 ) else (

     echo !RABBITMQ_SERVICENAME! service is already present - only updating service parameters

 )

@@ -204,7 +204,7 @@ set ERLANG_SERVICE_ARGUMENTS= ^
 -sasl sasl_error_logger false ^

 -rabbit error_logger {file,\""!LOGS:\=/!"\"} ^

 -rabbit sasl_error_logger {file,\""!SASL_LOGS:\=/!"\"} ^

--os_mon start_cpu_sup true ^

+-os_mon start_cpu_sup false ^

 -os_mon start_disksup false ^

 -os_mon start_memsup false ^

 -mnesia dir \""!RABBITMQ_MNESIA_DIR:\=/!"\" ^

diff --git a/scripts/rabbitmqctl b/scripts/rabbitmqctl
index 9a11c3b3..4aad6b8f 100755
--- a/scripts/rabbitmqctl
+++ b/scripts/rabbitmqctl
@@ -12,14 +12,20 @@
 ##  The Original Code is RabbitMQ.
 ##
 ##  The Initial Developer of the Original Code is VMware, Inc.
-##  Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+##  Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 ##
 
+# Get default settings with user overrides for (RABBITMQ_)<var_name>
+# Non-empty defaults should be set in rabbitmq-env
 . `dirname $0`/rabbitmq-env
 
+##--- Set environment vars RABBITMQ_<var_name> to defaults if not set
+
 [ "x" = "x$RABBITMQ_NODENAME" ] && RABBITMQ_NODENAME=${NODENAME}
 [ "x" = "x$RABBITMQ_CTL_ERL_ARGS" ] && RABBITMQ_CTL_ERL_ARGS=${CTL_ERL_ARGS}
 
+##--- End of overridden <var_name> variables
+
 exec erl \
     -pa "${RABBITMQ_HOME}/ebin" \
     -noinput \
diff --git a/scripts/rabbitmqctl.bat b/scripts/rabbitmqctl.bat
index a74a91fd..f37fae48 100644..100755
--- a/scripts/rabbitmqctl.bat
+++ b/scripts/rabbitmqctl.bat
@@ -12,7 +12,7 @@ REM
 REM  The Original Code is RabbitMQ.

 REM

 REM  The Initial Developer of the Original Code is VMware, Inc.

-REM  Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.

+REM  Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.

 REM

 

 setlocal

diff --git a/src/credit_flow.erl b/src/credit_flow.erl
new file mode 100644
index 00000000..ba99811f
--- /dev/null
+++ b/src/credit_flow.erl
@@ -0,0 +1,128 @@
+%% The contents of this file are subject to the Mozilla Public License
+%% Version 1.1 (the "License"); you may not use this file except in
+%% compliance with the License. You may obtain a copy of the License
+%% at http://www.mozilla.org/MPL/
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and
+%% limitations under the License.
+%%
+%% The Original Code is RabbitMQ.
+%%
+%% The Initial Developer of the Original Code is VMware, Inc.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
+%%
+
+-module(credit_flow).
+
+%% Credit flow is controlled by a credit specification - a
+%% {InitialCredit, MoreCreditAfter} tuple. For the message sender,
+%% credit starts at InitialCredit and is decremented with every
+%% message sent. The message receiver grants more credit to the sender
+%% by sending it a {bump_credit, ...} control message after receiving
+%% MoreCreditAfter messages. The sender should pass this message in to
+%% handle_bump_msg/1. The sender should block when it goes below 0
+%% (check by invoking blocked/0). If a process is both a sender and a
+%% receiver it will not grant any more credit to its senders when it
+%% is itself blocked - thus the only processes that need to check
+%% blocked/0 are ones that read from network sockets.
+
+-define(DEFAULT_CREDIT, {200, 50}).
+
+-export([send/1, send/2, ack/1, ack/2, handle_bump_msg/1, blocked/0]).
+-export([peer_down/1]).
+
+%%----------------------------------------------------------------------------
+
+-ifdef(use_specs).
+
+-opaque(bump_msg() :: {pid(), non_neg_integer()}).
+-type(credit_spec() :: {non_neg_integer(), non_neg_integer()}).
+
+-spec(send/1 :: (pid()) -> 'ok').
+-spec(send/2 :: (pid(), credit_spec()) -> 'ok').
+-spec(ack/1 :: (pid()) -> 'ok').
+-spec(ack/2 :: (pid(), credit_spec()) -> 'ok').
+-spec(handle_bump_msg/1 :: (bump_msg()) -> 'ok').
+-spec(blocked/0 :: () -> boolean()).
+-spec(peer_down/1 :: (pid()) -> 'ok').
+
+-endif.
+
+%%----------------------------------------------------------------------------
+
+%% There are two "flows" here; of messages and of credit, going in
+%% opposite directions. The variable names "From" and "To" refer to
+%% the flow of credit, but the function names refer to the flow of
+%% messages. This is the clearest I can make it (since the function
+%% names form the API and want to make sense externally, while the
+%% variable names are used in credit bookkeeping and want to make
+%% sense internally).
+
+%% For any given pair of processes, ack/2 and send/2 must always be
+%% called with the same credit_spec().
+
+send(From) -> send(From, ?DEFAULT_CREDIT).
+
+send(From, {InitialCredit, _MoreCreditAfter}) ->
+    update({credit_from, From}, InitialCredit,
+           fun (1) -> block(From),
+                      0;
+               (C) -> C - 1
+           end).
+
+ack(To) -> ack(To, ?DEFAULT_CREDIT).
+
+ack(To, {_InitialCredit, MoreCreditAfter}) ->
+    update({credit_to, To}, MoreCreditAfter,
+           fun (1) -> grant(To, MoreCreditAfter),
+                      MoreCreditAfter;
+               (C) -> C - 1
+           end).
+
+handle_bump_msg({From, MoreCredit}) ->
+    update({credit_from, From}, 0,
+           fun (C) when C =< 0 andalso C + MoreCredit > 0 -> unblock(From),
+                                                             C + MoreCredit;
+               (C)                                        -> C + MoreCredit
+           end).
+
+blocked() -> get(credit_blocked, []) =/= [].
+
+peer_down(Peer) ->
+    %% In theory we could also remove it from credit_deferred here, but it
+    %% doesn't really matter; at some point later we will drain
+    %% credit_deferred and thus send messages into the void...
+    unblock(Peer),
+    erase({credit_from, Peer}),
+    erase({credit_to, Peer}),
+    ok.
+
+%% --------------------------------------------------------------------------
+
+grant(To, Quantity) ->
+    Msg = {bump_credit, {self(), Quantity}},
+    case blocked() of
+        false -> To ! Msg;
+        true  -> update(credit_deferred, [],
+                        fun (Deferred) -> [{To, Msg} | Deferred] end)
+    end.
+
+block(From) -> update(credit_blocked, [], fun (Blocks) -> [From | Blocks] end).
+
+unblock(From) ->
+    update(credit_blocked, [], fun (Blocks) -> Blocks -- [From] end),
+    case blocked() of
+        false -> [To ! Msg || {To, Msg} <- get(credit_deferred, [])],
+                 erase(credit_deferred);
+        true  -> ok
+    end.
+
+get(Key, Default) ->
+    case get(Key) of
+        undefined -> Default;
+        Value     -> Value
+    end.
+
+update(Key, Default, Fun) -> put(Key, Fun(get(Key, Default))), ok.
diff --git a/src/delegate.erl b/src/delegate.erl
index edb4eba4..d595e481 100644
--- a/src/delegate.erl
+++ b/src/delegate.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(delegate).
diff --git a/src/delegate_sup.erl b/src/delegate_sup.erl
index 4c131a6c..2a8b915b 100644
--- a/src/delegate_sup.erl
+++ b/src/delegate_sup.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(delegate_sup).
diff --git a/src/dtree.erl b/src/dtree.erl
new file mode 100644
index 00000000..ca2d30cf
--- /dev/null
+++ b/src/dtree.erl
@@ -0,0 +1,163 @@
+%% The contents of this file are subject to the Mozilla Public License
+%% Version 1.1 (the "License"); you may not use this file except in
+%% compliance with the License. You may obtain a copy of the License
+%% at http://www.mozilla.org/MPL/
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and
+%% limitations under the License.
+%%
+%% The Original Code is RabbitMQ.
+%%
+%% The Initial Developer of the Original Code is VMware, Inc.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
+%%
+
+%% A dual-index tree.
+%%
+%% Entries have the following shape:
+%%
+%% +----+--------------------+---+
+%% | PK | SK1, SK2, ..., SKN | V |
+%% +----+--------------------+---+
+%%
+%% i.e. a primary key, set of secondary keys, and a value.
+%%
+%% There can be only one entry per primary key, but secondary keys may
+%% appear in multiple entries.
+%%
+%% The set of secondary keys must be non-empty. Or, to put it another
+%% way, entries only exist while their secondary key set is non-empty.
+
+-module(dtree).
+
+-export([empty/0, insert/4, take/3, take/2, take_all/2,
+         is_defined/2, is_empty/1, smallest/1, size/1]).
+
+%%----------------------------------------------------------------------------
+
+-ifdef(use_specs).
+
+-export_type([?MODULE/0]).
+
+-opaque(?MODULE()  :: {gb_tree(), gb_tree()}).
+
+-type(pk()         :: any()).
+-type(sk()         :: any()).
+-type(val()        :: any()).
+-type(kv()         :: {pk(), val()}).
+
+-spec(empty/0      :: () -> ?MODULE()).
+-spec(insert/4     :: (pk(), [sk()], val(), ?MODULE()) -> ?MODULE()).
+-spec(take/3       :: ([pk()], sk(), ?MODULE()) -> {[kv()], ?MODULE()}).
+-spec(take/2       :: (sk(), ?MODULE()) -> {[kv()], ?MODULE()}).
+-spec(take_all/2   :: (sk(), ?MODULE()) -> {[kv()], ?MODULE()}).
+-spec(is_defined/2 :: (sk(), ?MODULE()) -> boolean()).
+-spec(is_empty/1   :: (?MODULE()) -> boolean()).
+-spec(smallest/1   :: (?MODULE()) -> kv()).
+-spec(size/1       :: (?MODULE()) -> non_neg_integer()).
+
+-endif.
+
+%%----------------------------------------------------------------------------
+
+empty() -> {gb_trees:empty(), gb_trees:empty()}.
+
+%% Insert an entry. Fails if there already is an entry with the given
+%% primary key.
+insert(PK, [], V, {P, S}) ->
+    %% dummy insert to force error if PK exists
+    gb_trees:insert(PK, {gb_sets:empty(), V}, P),
+    {P, S};
+insert(PK, SKs, V, {P, S}) ->
+    {gb_trees:insert(PK, {gb_sets:from_list(SKs), V}, P),
+     lists:foldl(fun (SK, S0) ->
+                         case gb_trees:lookup(SK, S0) of
+                             {value, PKS} -> PKS1 = gb_sets:insert(PK, PKS),
+                                             gb_trees:update(SK, PKS1, S0);
+                             none         -> PKS = gb_sets:singleton(PK),
+                                             gb_trees:insert(SK, PKS, S0)
+                         end
+                 end, S, SKs)}.
+
+%% Remove the given secondary key from the entries of the given
+%% primary keys, returning the primary-key/value pairs of any entries
+%% that were dropped as the result (i.e. due to their secondary key
+%% set becoming empty). It is ok for the given primary keys and/or
+%% secondary key to not exist.
+take(PKs, SK, {P, S}) ->
+    case gb_trees:lookup(SK, S) of
+        none         -> {[], {P, S}};
+        {value, PKS} -> TakenPKS = gb_sets:from_list(PKs),
+                        PKSInter = gb_sets:intersection(PKS, TakenPKS),
+                        PKSDiff  = gb_sets_difference  (PKS, PKSInter),
+                        {KVs, P1} = take2(PKSInter, SK, P),
+                        {KVs, {P1, case gb_sets:is_empty(PKSDiff) of
+                                       true  -> gb_trees:delete(SK, S);
+                                       false -> gb_trees:update(SK, PKSDiff, S)
+                                   end}}
+    end.
+
+%% Remove the given secondary key from all entries, returning the
+%% primary-key/value pairs of any entries that were dropped as the
+%% result (i.e. due to their secondary key set becoming empty). It is
+%% ok for the given secondary key to not exist.
+take(SK, {P, S}) ->
+    case gb_trees:lookup(SK, S) of
+        none         -> {[], {P, S}};
+        {value, PKS} -> {KVs, P1} = take2(PKS, SK, P),
+                        {KVs, {P1, gb_trees:delete(SK, S)}}
+    end.
+
+%% Drop all entries which contain the given secondary key, returning
+%% the primary-key/value pairs of these entries. It is ok for the
+%% given secondary key to not exist.
+take_all(SK, {P, S}) ->
+    case gb_trees:lookup(SK, S) of
+        none         -> {[], {P, S}};
+        {value, PKS} -> {KVs, SKS, P1} = take_all2(PKS, P),
+                        {KVs, {P1, prune(SKS, PKS, S)}}
+    end.
+
+is_defined(SK, {_P, S}) -> gb_trees:is_defined(SK, S).
+
+is_empty({P, _S}) -> gb_trees:is_empty(P).
+
+smallest({P, _S}) -> {K, {_SKS, V}} = gb_trees:smallest(P),
+                     {K, V}.
+
+size({P, _S}) -> gb_trees:size(P).
+
+%%----------------------------------------------------------------------------
+
+take2(PKS, SK, P) ->
+    gb_sets:fold(fun (PK, {KVs, P0}) ->
+                         {SKS, V} = gb_trees:get(PK, P0),
+                         SKS1 = gb_sets:delete(SK, SKS),
+                         case gb_sets:is_empty(SKS1) of
+                             true  -> KVs1 = [{PK, V} | KVs],
+                                      {KVs1, gb_trees:delete(PK, P0)};
+                             false -> {KVs,  gb_trees:update(PK, {SKS1, V}, P0)}
+                         end
+                 end, {[], P}, PKS).
+
+take_all2(PKS, P) ->
+    gb_sets:fold(fun (PK, {KVs, SKS0, P0}) ->
+                         {SKS, V} = gb_trees:get(PK, P0),
+                         {[{PK, V} | KVs], gb_sets:union(SKS, SKS0),
+                          gb_trees:delete(PK, P0)}
+                 end, {[], gb_sets:empty(), P}, PKS).
+
+prune(SKS, PKS, S) ->
+    gb_sets:fold(fun (SK0, S0) ->
+                         PKS1 = gb_trees:get(SK0, S0),
+                         PKS2 = gb_sets_difference(PKS1, PKS),
+                         case gb_sets:is_empty(PKS2) of
+                             true  -> gb_trees:delete(SK0, S0);
+                             false -> gb_trees:update(SK0, PKS2, S0)
+                         end
+                 end, S, SKS).
+
+gb_sets_difference(S1, S2) ->
+    gb_sets:fold(fun gb_sets:delete_any/2, S1, S2).
diff --git a/src/file_handle_cache.erl b/src/file_handle_cache.erl
index 6c3f1b5f..f3b4dbaf 100644
--- a/src/file_handle_cache.erl
+++ b/src/file_handle_cache.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(file_handle_cache).
@@ -125,8 +125,7 @@
 %% requesting process is considered to 'own' one more
 %% descriptor. release/0 is the inverse operation and releases a
 %% previously obtained descriptor. transfer/1 transfers ownership of a
-%% file descriptor between processes. It is non-blocking. Obtain is
-%% used to obtain permission to accept file descriptors. Obtain has a
+%% file descriptor between processes. It is non-blocking. Obtain has a
 %% lower limit, set by the ?OBTAIN_LIMIT/1 macro. File handles can use
 %% the entire limit, but will be evicted by obtain calls up to the
 %% point at which no more obtain calls can be satisfied by the obtains
@@ -144,9 +143,9 @@
 -behaviour(gen_server2).
 
 -export([register_callback/3]).
--export([open/3, close/1, read/2, append/2, sync/1, position/2, truncate/1,
-         current_virtual_offset/1, current_raw_offset/1, flush/1, copy/3,
-         set_maximum_since_use/1, delete/1, clear/1]).
+-export([open/3, close/1, read/2, append/2, needs_sync/1, sync/1, position/2,
+         truncate/1, current_virtual_offset/1, current_raw_offset/1, flush/1,
+         copy/3, set_maximum_since_use/1, delete/1, clear/1]).
 -export([obtain/0, release/0, transfer/1, set_limit/1, get_limit/0, info_keys/0,
          info/0, info/1]).
 -export([ulimit/0]).
@@ -262,7 +261,7 @@
 -endif.
 
 %%----------------------------------------------------------------------------
--define(INFO_KEYS, [obtain_count, obtain_limit]).
+-define(INFO_KEYS, [total_limit, total_used, sockets_limit, sockets_used]).
 
 %%----------------------------------------------------------------------------
 %% Public API
@@ -374,6 +373,13 @@ sync(Ref) ->
               end
       end).
 
+needs_sync(Ref) ->
+    with_handles(
+      [Ref],
+      fun ([#handle { is_dirty = false, write_buffer = [] }]) -> false;
+          ([_Handle])                                         -> true
+      end).
+
 position(Ref, NewOffset) ->
     with_flushed_handles(
       [Ref],
@@ -790,8 +796,10 @@ write_buffer(Handle = #handle { hdl = Hdl, offset = Offset,
 
 infos(Items, State) -> [{Item, i(Item, State)} || Item <- Items].
 
-i(obtain_count, #fhc_state{obtain_count = Count}) -> Count;
-i(obtain_limit, #fhc_state{obtain_limit = Limit}) -> Limit;
+i(total_limit,   #fhc_state{limit        = Limit})               -> Limit;
+i(total_used,    #fhc_state{open_count = C1, obtain_count = C2}) -> C1 + C2;
+i(sockets_limit, #fhc_state{obtain_limit = Limit})               -> Limit;
+i(sockets_used,  #fhc_state{obtain_count = Count})               -> Count;
 i(Item, _) -> throw({bad_argument, Item}).
 
 %%----------------------------------------------------------------------------
diff --git a/src/gatherer.erl b/src/gatherer.erl
index fe976b50..98b36038 100644
--- a/src/gatherer.erl
+++ b/src/gatherer.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(gatherer).
diff --git a/src/gen_server2.erl b/src/gen_server2.erl
index ab6c4e64..78bbbe06 100644
--- a/src/gen_server2.erl
+++ b/src/gen_server2.erl
@@ -31,13 +31,13 @@
 %% handle_pre_hibernate/1 then the default action is to hibernate.
 %%
 %% 6) init can return a 4th arg, {backoff, InitialTimeout,
-%% MinimumTimeout, DesiredHibernatePeriod} (all in
-%% milliseconds). Then, on all callbacks which can return a timeout
-%% (including init), timeout can be 'hibernate'. When this is the
-%% case, the current timeout value will be used (initially, the
-%% InitialTimeout supplied from init). After this timeout has
-%% occurred, hibernation will occur as normal. Upon awaking, a new
-%% current timeout value will be calculated.
+%% MinimumTimeout, DesiredHibernatePeriod} (all in milliseconds,
+%% 'infinity' does not make sense here). Then, on all callbacks which
+%% can return a timeout (including init), timeout can be
+%% 'hibernate'. When this is the case, the current timeout value will
+%% be used (initially, the InitialTimeout supplied from init). After
+%% this timeout has occurred, hibernation will occur as normal. Upon
+%% awaking, a new current timeout value will be calculated.
 %%
 %% The purpose is that the gen_server2 takes care of adjusting the
 %% current timeout value such that the process will increase the
@@ -73,7 +73,7 @@
 %% but where the second argument is specifically the priority_queue
 %% which contains the prioritised message_queue.
 
-%% All modifications are (C) 2009-2011 VMware, Inc.
+%% All modifications are (C) 2009-2012 VMware, Inc.
 
 %% ``The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -135,9 +135,10 @@
 %%%              Reason = normal | shutdown | Term, terminate(State) is called
 %%%
 %%%   terminate(Reason, State) Let the user module clean up
+%%%              Reason = normal | shutdown | {shutdown, Term} | Term
 %%%        always called when server terminates
 %%%
-%%%    ==> ok
+%%%    ==> ok | Term
 %%%
 %%%   handle_pre_hibernate(State)
 %%%
@@ -182,8 +183,6 @@
          multi_call/2, multi_call/3, multi_call/4,
          enter_loop/3, enter_loop/4, enter_loop/5, enter_loop/6, wake_hib/1]).
 
--export([behaviour_info/1]).
-
 %% System exports
 -export([system_continue/3,
          system_terminate/4,
@@ -200,12 +199,12 @@
                     timeout_state, queue, debug, prioritise_call,
                     prioritise_cast, prioritise_info}).
 
+-ifdef(use_specs).
+
 %%%=========================================================================
 %%%  Specs. These exist only to shut up dialyzer's warnings
 %%%=========================================================================
 
--ifdef(use_specs).
-
 -type(gs2_state() :: #gs2_state{}).
 
 -spec(handle_common_termination/3 ::
@@ -214,18 +213,58 @@
 -spec(pre_hibernate/1 :: (gs2_state()) -> no_return()).
 -spec(system_terminate/4 :: (_, _, _, gs2_state()) -> no_return()).
 
--endif.
+-type(millis() :: non_neg_integer()).
 
 %%%=========================================================================
 %%%  API
 %%%=========================================================================
 
+-callback init(Args :: term()) ->
+    {ok, State :: term()} |
+    {ok, State :: term(), timeout() | hibernate} |
+    {ok, State :: term(), timeout() | hibernate,
+     {backoff, millis(), millis(), millis()}} |
+    ignore |
+    {stop, Reason :: term()}.
+-callback handle_call(Request :: term(), From :: {pid(), Tag :: term()},
+                      State :: term()) ->
+    {reply, Reply :: term(), NewState :: term()} |
+    {reply, Reply :: term(), NewState :: term(), timeout() | hibernate} |
+    {noreply, NewState :: term()} |
+    {noreply, NewState :: term(), timeout() | hibernate} |
+    {stop, Reason :: term(),
+     Reply :: term(), NewState :: term()}.
+-callback handle_cast(Request :: term(), State :: term()) ->
+    {noreply, NewState :: term()} |
+    {noreply, NewState :: term(), timeout() | hibernate} |
+    {stop, Reason :: term(), NewState :: term()}.
+-callback handle_info(Info :: term(), State :: term()) ->
+    {noreply, NewState :: term()} |
+    {noreply, NewState :: term(), timeout() | hibernate} |
+    {stop, Reason :: term(), NewState :: term()}.
+-callback terminate(Reason :: (normal | shutdown | {shutdown, term()} | term()),
+                    State :: term()) ->
+    ok | term().
+-callback code_change(OldVsn :: (term() | {down, term()}), State :: term(),
+                      Extra :: term()) ->
+    {ok, NewState :: term()} | {error, Reason :: term()}.
+
+%% It's not possible to define "optional" -callbacks, so putting specs
+%% for handle_pre_hibernate/1 and handle_post_hibernate/1 will result
+%% in warnings (the same applied for the behaviour_info before).
+
+-else.
+
+-export([behaviour_info/1]).
+
 behaviour_info(callbacks) ->
     [{init,1},{handle_call,3},{handle_cast,2},{handle_info,2},
      {terminate,2},{code_change,3}];
 behaviour_info(_Other) ->
     undefined.
 
+-endif.
+
 %%%  -----------------------------------------------------------------
 %%% Starts a generic server.
 %%% start(Mod, Args, Options)
@@ -1079,7 +1118,7 @@ get_proc_name({local, Name}) ->
             exit(process_not_registered)
     end;
 get_proc_name({global, Name}) ->
-    case global:safe_whereis_name(Name) of
+    case whereis_name(Name) of
         undefined ->
             exit(process_not_registered_globally);
         Pid when Pid =:= self() ->
@@ -1101,7 +1140,7 @@ get_parent() ->
 name_to_pid(Name) ->
     case whereis(Name) of
         undefined ->
-            case global:safe_whereis_name(Name) of
+            case whereis_name(Name) of
                 undefined ->
                     exit(could_not_find_registerd_name);
                 Pid ->
@@ -1111,6 +1150,20 @@ name_to_pid(Name) ->
             Pid
     end.
 
+whereis_name(Name) ->
+    case ets:lookup(global_names, Name) of
+    [{_Name, Pid, _Method, _RPid, _Ref}] ->
+        if node(Pid) == node() ->
+            case is_process_alive(Pid) of
+            true  -> Pid;
+            false -> undefined
+            end;
+           true ->
+            Pid
+        end;
+    [] -> undefined
+    end.
+
 find_prioritisers(GS2State = #gs2_state { mod = Mod }) ->
     PrioriCall = function_exported_or_default(
                    Mod, 'prioritise_call', 3,
diff --git a/src/gm.erl b/src/gm.erl
index a9ddf708..a88d9d3e 100644
--- a/src/gm.erl
+++ b/src/gm.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(gm).
@@ -57,8 +57,8 @@
 %% you wish to be passed into the callback module's functions. The
 %% joined/2 function will be called when we have joined the group,
 %% with the arguments passed to start_link and a list of the current
-%% members of the group. See the comments in behaviour_info/1 below
-%% for further details of the callback functions.
+%% members of the group. See the callbacks specs and the comments
+%% below for further details of the callback functions.
 %%
 %% leave/1
 %% Provide the Pid. Removes the Pid from the group. The callback
@@ -378,7 +378,9 @@
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2,
          code_change/3, prioritise_info/2]).
 
+-ifndef(use_specs).
 -export([behaviour_info/1]).
+-endif.
 
 -export([table_definitions/0]).
 
@@ -431,56 +433,63 @@
 -spec(confirmed_broadcast/2 :: (pid(), any()) -> 'ok').
 -spec(group_members/1 :: (pid()) -> [pid()]).
 
--endif.
+%% The joined, members_changed and handle_msg callbacks can all
+%% return any of the following terms:
+%%
+%% 'ok' - the callback function returns normally
+%%
+%% {'stop', Reason} - the callback indicates the member should
+%% stop with reason Reason and should leave the group.
+%%
+%% {'become', Module, Args} - the callback indicates that the
+%% callback module should be changed to Module and that the
+%% callback functions should now be passed the arguments
+%% Args. This allows the callback module to be dynamically
+%% changed.
+
+%% Called when we've successfully joined the group. Supplied with
+%% Args provided in start_link, plus current group members.
+-callback joined(Args :: term(), Members :: [pid()]) ->
+    ok | {stop, Reason :: term()} | {become, Module :: atom(), Args :: any()}.
+
+%% Supplied with Args provided in start_link, the list of new
+%% members and the list of members previously known to us that
+%% have since died. Note that if a member joins and dies very
+%% quickly, it's possible that we will never see that member
+%% appear in either births or deaths. However we are guaranteed
+%% that (1) we will see a member joining either in the births
+%% here, or in the members passed to joined/2 before receiving
+%% any messages from it; and (2) we will not see members die that
+%% we have not seen born (or supplied in the members to
+%% joined/2).
+-callback members_changed(Args :: term(), Births :: [pid()],
+                          Deaths :: [pid()]) ->
+    ok | {stop, Reason :: term()} | {become, Module :: atom(), Args :: any()}.
+
+%% Supplied with Args provided in start_link, the sender, and the
+%% message. This does get called for messages injected by this
+%% member, however, in such cases, there is no special
+%% significance of this invocation: it does not indicate that the
+%% message has made it to any other members, let alone all other
+%% members.
+-callback handle_msg(Args :: term(), From :: pid(), Message :: term()) ->
+    ok | {stop, Reason :: term()} | {become, Module :: atom(), Args :: any()}.
+
+%% Called on gm member termination as per rules in gen_server,
+%% with the Args provided in start_link plus the termination
+%% Reason.
+-callback terminate(Args :: term(), Reason :: term()) ->
+    ok | term().
+
+-else.
 
 behaviour_info(callbacks) ->
-    [
-     %% The joined, members_changed and handle_msg callbacks can all
-     %% return any of the following terms:
-     %%
-     %% 'ok' - the callback function returns normally
-     %%
-     %% {'stop', Reason} - the callback indicates the member should
-     %% stop with reason Reason and should leave the group.
-     %%
-     %% {'become', Module, Args} - the callback indicates that the
-     %% callback module should be changed to Module and that the
-     %% callback functions should now be passed the arguments
-     %% Args. This allows the callback module to be dynamically
-     %% changed.
-
-     %% Called when we've successfully joined the group. Supplied with
-     %% Args provided in start_link, plus current group members.
-     {joined, 2},
-
-     %% Supplied with Args provided in start_link, the list of new
-     %% members and the list of members previously known to us that
-     %% have since died. Note that if a member joins and dies very
-     %% quickly, it's possible that we will never see that member
-     %% appear in either births or deaths. However we are guaranteed
-     %% that (1) we will see a member joining either in the births
-     %% here, or in the members passed to joined/2 before receiving
-     %% any messages from it; and (2) we will not see members die that
-     %% we have not seen born (or supplied in the members to
-     %% joined/2).
-     {members_changed, 3},
-
-     %% Supplied with Args provided in start_link, the sender, and the
-     %% message. This does get called for messages injected by this
-     %% member, however, in such cases, there is no special
-     %% significance of this invocation: it does not indicate that the
-     %% message has made it to any other members, let alone all other
-     %% members.
-     {handle_msg, 3},
-
-     %% Called on gm member termination as per rules in gen_server,
-     %% with the Args provided in start_link plus the termination
-     %% Reason.
-     {terminate, 2}
-    ];
+    [{joined, 2}, {members_changed, 3}, {handle_msg, 3}, {terminate, 2}];
 behaviour_info(_Other) ->
     undefined.
 
+-endif.
+
 create_tables() ->
     create_tables([?TABLE]).
 
@@ -524,7 +533,7 @@ init([GroupName, Module, Args]) ->
                   group_name       = GroupName,
                   module           = Module,
                   view             = undefined,
-                  pub_count        = 0,
+                  pub_count        = -1,
                   members_state    = undefined,
                   callback_args    = Args,
                   confirms         = queue:new(),
@@ -584,33 +593,39 @@ handle_call({add_on_right, NewMember}, _From,
     %%       without a catchup message being received by
     %%       the joining member.
 
-    Group = record_new_member_in_group(
-              GroupName, Self, NewMember,
-              fun (Group1) ->
-                      View1 = group_to_view(Group1),
-                      ok = send_right(NewMember, View1,
-                                      {catchup, Self, view_version(View1),
-                                       prepare_members_state(MembersState)})
-              end),
+    {MembersState1, Group} =
+      record_new_member_in_group(
+        GroupName, Self, NewMember,
+        fun (Group1) ->
+                View1 = group_to_view(Group1),
+                MembersState1 = remove_erased_members(MembersState, View1),
+                ok = send_right(NewMember, View1,
+                                {catchup, Self, view_version(View1),
+                                 prepare_members_state(MembersState1)}),
+                MembersState1
+        end),
     View2 = group_to_view(Group),
-    State1 = check_neighbours(State #state { view = View2 }),
+    State1 = check_neighbours(State #state { view          = View2,
+                                             members_state = MembersState1 }),
     Result = callback_view_changed(Args, Module, View, View2),
     handle_callback_result({Result, {ok, Group}, State1}).
 
 
 handle_cast({?TAG, ReqVer, Msg},
             State = #state { view          = View,
+                             members_state = MembersState,
                              group_name    = GroupName,
                              module        = Module,
                              callback_args = Args }) ->
     {Result, State1} =
         case needs_view_update(ReqVer, View) of
-            true ->
-                View1 = group_to_view(read_group(GroupName)),
-                {callback_view_changed(Args, Module, View, View1),
-                 check_neighbours(State #state { view = View1 })};
-            false ->
-                {ok, State}
+            true  -> View1 = group_to_view(read_group(GroupName)),
+                     MemberState1 = remove_erased_members(MembersState, View1),
+                     {callback_view_changed(Args, Module, View, View1),
+                      check_neighbours(
+                        State #state { view          = View1,
+                                       members_state = MemberState1 })};
+            false -> {ok, State}
         end,
     handle_callback_result(
       if_callback_success(
@@ -674,22 +689,21 @@ handle_info({'DOWN', MRef, process, _Pid, _Reason},
         _ ->
             View1 =
                 group_to_view(record_dead_member_in_group(Member, GroupName)),
-            State1 = State #state { view = View1 },
             {Result, State2} =
                 case alive_view_members(View1) of
                     [Self] ->
-                        maybe_erase_aliases(
-                          State1 #state {
+                        {Result1, State1} = maybe_erase_aliases(State, View1),
+                        {Result1, State1 #state {
                             members_state = blank_member_state(),
-                            confirms      = purge_confirms(Confirms) });
+                            confirms      = purge_confirms(Confirms) }};
                     _ ->
                         %% here we won't be pointing out any deaths:
                         %% the concern is that there maybe births
                         %% which we'd otherwise miss.
                         {callback_view_changed(Args, Module, View, View1),
-                         State1}
+                         check_neighbours(State #state { view = View1 })}
                 end,
-            handle_callback_result({Result, check_neighbours(State2)})
+            handle_callback_result({Result, State2})
     end.
 
 
@@ -702,9 +716,13 @@ terminate(Reason, State = #state { module        = Module,
 code_change(_OldVsn, State, _Extra) ->
     {ok, State}.
 
-prioritise_info(flush,                                   _State) -> 1;
-prioritise_info({'DOWN', _MRef, process, _Pid, _Reason}, _State) -> 1;
-prioritise_info(_                                      , _State) -> 0.
+prioritise_info(flush, _State) ->
+    1;
+prioritise_info({'DOWN', _MRef, process, _Pid, _Reason},
+                #state { members_state = MS }) when MS /= undefined ->
+    1;
+prioritise_info(_, _State) ->
+    0.
 
 
 handle_msg(check_neighbours, State) ->
@@ -812,8 +830,8 @@ handle_msg({activity, Left, Activity},
     State1 = State #state { members_state = MembersState1,
                             confirms      = Confirms1 },
     Activity3 = activity_finalise(Activity1),
-    {Result, State2} = maybe_erase_aliases(State1),
-    ok = maybe_send_activity(Activity3, State2),
+    ok = maybe_send_activity(Activity3, State1),
+    {Result, State2} = maybe_erase_aliases(State1, View),
     if_callback_success(
       Result, fun activity_true/3, fun activity_false/3, Activity3, State2);
 
@@ -846,13 +864,14 @@ internal_broadcast(Msg, From, State = #state { self             = Self,
                                                confirms         = Confirms,
                                                callback_args    = Args,
                                                broadcast_buffer = Buffer }) ->
+    PubCount1 = PubCount + 1,
     Result = Module:handle_msg(Args, get_pid(Self), Msg),
-    Buffer1 = [{PubCount, Msg} | Buffer],
+    Buffer1 = [{PubCount1, Msg} | Buffer],
     Confirms1 = case From of
                     none -> Confirms;
-                    _    -> queue:in({PubCount, From}, Confirms)
+                    _    -> queue:in({PubCount1, From}, Confirms)
                 end,
-    State1 = State #state { pub_count        = PubCount + 1,
+    State1 = State #state { pub_count        = PubCount1,
                             confirms         = Confirms1,
                             broadcast_buffer = Buffer1 },
     case From =/= none of
@@ -867,14 +886,17 @@ flush_broadcast_buffer(State = #state { broadcast_buffer = [] }) ->
     State;
 flush_broadcast_buffer(State = #state { self             = Self,
                                         members_state    = MembersState,
-                                        broadcast_buffer = Buffer }) ->
+                                        broadcast_buffer = Buffer,
+                                        pub_count        = PubCount }) ->
+    [{PubCount, _Msg}|_] = Buffer, %% ASSERTION match on PubCount
     Pubs = lists:reverse(Buffer),
     Activity = activity_cons(Self, Pubs, [], activity_nil()),
     ok = maybe_send_activity(activity_finalise(Activity), State),
     MembersState1 = with_member(
                       fun (Member = #member { pending_ack = PA }) ->
                               PA1 = queue:join(PA, queue:from_list(Pubs)),
-                              Member #member { pending_ack = PA1 }
+                              Member #member { pending_ack = PA1,
+                                               last_pub = PubCount }
                       end, Self, MembersState),
     State #state { members_state    = MembersState1,
                    broadcast_buffer = [] }.
@@ -1069,7 +1091,7 @@ record_dead_member_in_group(Member, GroupName) ->
     Group.
 
 record_new_member_in_group(GroupName, Left, NewMember, Fun) ->
-    {atomic, Group} =
+    {atomic, {Result, Group}} =
         mnesia:sync_transaction(
           fun () ->
                   [#gm_group { members = Members, version = Ver } = Group1] =
@@ -1079,11 +1101,11 @@ record_new_member_in_group(GroupName, Left, NewMember, Fun) ->
                   Members1 = Prefix ++ [Left, NewMember | Suffix],
                   Group2 = Group1 #gm_group { members = Members1,
                                               version = Ver + 1 },
-                  ok = Fun(Group2),
+                  Result = Fun(Group2),
                   mnesia:write(Group2),
-                  Group2
+                  {Result, Group2}
           end),
-    Group.
+    {Result, Group}.
 
 erase_members_in_group(Members, GroupName) ->
     DeadMembers = [{dead, Id} || Id <- Members],
@@ -1106,10 +1128,10 @@ erase_members_in_group(Members, GroupName) ->
 
 maybe_erase_aliases(State = #state { self          = Self,
                                      group_name    = GroupName,
-                                     view          = View,
+                                     view          = View0,
                                      members_state = MembersState,
                                      module        = Module,
-                                     callback_args = Args }) ->
+                                     callback_args = Args }, View) ->
     #view_member { aliases = Aliases } = fetch_view_member(Self, View),
     {Erasable, MembersState1}
         = ?SETS:fold(
@@ -1124,11 +1146,11 @@ maybe_erase_aliases(State = #state { self          = Self,
              end, {[], MembersState}, Aliases),
     State1 = State #state { members_state = MembersState1 },
     case Erasable of
-        [] -> {ok, State1};
+        [] -> {ok, State1 #state { view = View }};
         _  -> View1 = group_to_view(
                         erase_members_in_group(Erasable, GroupName)),
-              {callback_view_changed(Args, Module, View, View1),
-               State1 #state { view = View1 }}
+              {callback_view_changed(Args, Module, View0, View1),
+               check_neighbours(State1 #state { view = View1 })}
     end.
 
 can_erase_view_member(Self, Self, _LA, _LP) -> false;
@@ -1275,6 +1297,12 @@ make_member(GroupName) ->
         {error, not_found}              -> ?VERSION_START
     end, self()}.
 
+remove_erased_members(MembersState, View) ->
+    lists:foldl(fun (Id, MembersState1) ->
+                    store_member(Id, find_member_or_blank(Id, MembersState),
+                                 MembersState1)
+                end, blank_member_state(), all_known_members(View)).
+
 get_pid({_Version, Pid}) -> Pid.
 
 get_pids(Ids) -> [Pid || {_Version, Pid} <- Ids].
@@ -1305,16 +1333,30 @@ send_right(Right, View, Msg) ->
     ok = gen_server2:cast(get_pid(Right), {?TAG, view_version(View), Msg}).
 
 callback(Args, Module, Activity) ->
-    lists:foldl(
-      fun ({Id, Pubs, _Acks}, ok) ->
-              lists:foldl(fun ({_PubNum, Pub}, ok) ->
-                                  Module:handle_msg(Args, get_pid(Id), Pub);
-                              (_, Error) ->
-                                  Error
-                          end, ok, Pubs);
-          (_, Error) ->
-              Error
-      end, ok, Activity).
+    Result =
+      lists:foldl(
+        fun ({Id, Pubs, _Acks}, {Args1, Module1, ok}) ->
+                lists:foldl(fun ({_PubNum, Pub}, Acc = {Args2, Module2, ok}) ->
+                                    case Module2:handle_msg(
+                                           Args2, get_pid(Id), Pub) of
+                                        ok ->
+                                            Acc;
+                                        {become, Module3, Args3} ->
+                                            {Args3, Module3, ok};
+                                        {stop, _Reason} = Error ->
+                                            Error
+                                    end;
+                                (_, Error = {stop, _Reason}) ->
+                                    Error
+                            end, {Args1, Module1, ok}, Pubs);
+            (_, Error = {stop, _Reason}) ->
+                Error
+        end, {Args, Module, ok}, Activity),
+    case Result of
+        {Args, Module, ok}      -> ok;
+        {Args1, Module1, ok}    -> {become, Module1, Args1};
+        {stop, _Reason} = Error -> Error
+    end.
 
 callback_view_changed(Args, Module, OldView, NewView) ->
     OldMembers = all_known_members(OldView),
diff --git a/src/gm_soak_test.erl b/src/gm_soak_test.erl
index 5e5a3a5a..57217541 100644
--- a/src/gm_soak_test.erl
+++ b/src/gm_soak_test.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(gm_soak_test).
diff --git a/src/gm_speed_test.erl b/src/gm_speed_test.erl
index defb0f29..dad75bd4 100644
--- a/src/gm_speed_test.erl
+++ b/src/gm_speed_test.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(gm_speed_test).
diff --git a/src/gm_tests.erl b/src/gm_tests.erl
index ca0ffd64..0a2d4204 100644
--- a/src/gm_tests.erl
+++ b/src/gm_tests.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(gm_tests).
diff --git a/src/lqueue.erl b/src/lqueue.erl
index 04b40706..c4e046b5 100644
--- a/src/lqueue.erl
+++ b/src/lqueue.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2011-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2011-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(lqueue).
diff --git a/src/mirrored_supervisor.erl b/src/mirrored_supervisor.erl
index 6e8f96d9..4fc488b8 100644
--- a/src/mirrored_supervisor.erl
+++ b/src/mirrored_supervisor.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2011-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(mirrored_supervisor).
@@ -120,8 +120,6 @@
          delete_child/2, terminate_child/2,
          which_children/1, count_children/1, check_childspecs/1]).
 
--export([behaviour_info/1]).
-
 -behaviour(?GEN_SERVER).
 -behaviour(?SUPERVISOR).
 
@@ -142,34 +140,24 @@
 
 -ifdef(use_specs).
 
--type child()    :: pid() | 'undefined'.
--type child_id() :: term().
--type mfargs()   :: {M :: module(), F :: atom(), A :: [term()] | 'undefined'}.
--type modules()  :: [module()] | 'dynamic'.
--type restart()  :: 'permanent' | 'transient' | 'temporary'.
--type shutdown() :: 'brutal_kill' | timeout().
--type worker()   :: 'worker' | 'supervisor'.
--type sup_name() :: {'local', Name :: atom()} | {'global', Name :: atom()}.
--type sup_ref()  :: (Name :: atom())
-                  | {Name :: atom(), Node :: node()}
-                  | {'global', Name :: atom()}
-                  | pid().
--type child_spec() :: {Id :: child_id(),
-                       StartFunc :: mfargs(),
-                       Restart :: restart(),
-                       Shutdown :: shutdown(),
-                       Type :: worker(),
-                       Modules :: modules()}.
+%%--------------------------------------------------------------------------
+%% Callback behaviour
+%%--------------------------------------------------------------------------
+
+-callback init(Args :: term()) ->
+    {ok, {{RestartStrategy :: supervisor2:strategy(),
+           MaxR :: non_neg_integer(),
+           MaxT :: non_neg_integer()},
+           [ChildSpec :: supervisor2:child_spec()]}}
+    | ignore.
+
+%%--------------------------------------------------------------------------
+%% Specs
+%%--------------------------------------------------------------------------
 
 -type startlink_err() :: {'already_started', pid()} | 'shutdown' | term().
 -type startlink_ret() :: {'ok', pid()} | 'ignore' | {'error', startlink_err()}.
 
--type startchild_err() :: 'already_present'
-                        | {'already_started', Child :: child()} | term().
--type startchild_ret() :: {'ok', Child :: child()}
-                        | {'ok', Child :: child(), Info :: term()}
-                        | {'error', startchild_err()}.
-
 -type group_name() :: any().
 
 -spec start_link(GroupName, Module, Args) -> startlink_ret() when
@@ -178,54 +166,26 @@
       Args :: term().
 
 -spec start_link(SupName, GroupName, Module, Args) -> startlink_ret() when
-      SupName :: sup_name(),
+      SupName :: supervisor2:sup_name(),
       GroupName :: group_name(),
       Module :: module(),
       Args :: term().
 
--spec start_child(SupRef, ChildSpec) -> startchild_ret() when
-      SupRef :: sup_ref(),
-      ChildSpec :: child_spec() | (List :: [term()]).
-
--spec restart_child(SupRef, Id) -> Result when
-      SupRef :: sup_ref(),
-      Id :: child_id(),
-      Result :: {'ok', Child :: child()}
-              | {'ok', Child :: child(), Info :: term()}
-              | {'error', Error},
-      Error :: 'running' | 'not_found' | 'simple_one_for_one' | term().
-
--spec delete_child(SupRef, Id) -> Result when
-      SupRef :: sup_ref(),
-      Id :: child_id(),
-      Result :: 'ok' | {'error', Error},
-      Error :: 'running' | 'not_found' | 'simple_one_for_one'.
-
--spec terminate_child(SupRef, Id) -> Result when
-      SupRef :: sup_ref(),
-      Id :: pid() | child_id(),
-      Result :: 'ok' | {'error', Error},
-      Error :: 'not_found' | 'simple_one_for_one'.
-
--spec which_children(SupRef) -> [{Id,Child,Type,Modules}] when
-      SupRef :: sup_ref(),
-      Id :: child_id() | 'undefined',
-      Child :: child(),
-      Type :: worker(),
-      Modules :: modules().
-
--spec check_childspecs(ChildSpecs) -> Result when
-      ChildSpecs :: [child_spec()],
-      Result :: 'ok' | {'error', Error :: term()}.
-
 -spec start_internal(Group, ChildSpecs) -> Result when
       Group :: group_name(),
-      ChildSpecs :: [child_spec()],
-      Result :: startlink_ret().
+      ChildSpecs :: [supervisor2:child_spec()],
+      Result :: supervisor2:startlink_ret().
 
 -spec create_tables() -> Result when
       Result :: 'ok'.
 
+-else.
+
+-export([behaviour_info/1]).
+
+behaviour_info(callbacks) -> [{init,1}];
+behaviour_info(_Other)    -> undefined.
+
 -endif.
 
 %%----------------------------------------------------------------------------
@@ -265,11 +225,8 @@ which_children(Sup)         -> fold(which_children, Sup, fun lists:append/2).
 count_children(Sup)         -> fold(count_children, Sup, fun add_proplists/2).
 check_childspecs(Specs)     -> ?SUPERVISOR:check_childspecs(Specs).
 
-behaviour_info(callbacks) -> [{init,1}];
-behaviour_info(_Other)    -> undefined.
-
-call(Sup, Msg) ->
-    ?GEN_SERVER:call(child(Sup, mirroring), Msg, infinity).
+call(Sup, Msg) -> ?GEN_SERVER:call(mirroring(Sup), Msg, infinity).
+cast(Sup, Msg) -> ?GEN_SERVER:cast(mirroring(Sup), Msg).
 
 find_call(Sup, Id, Msg) ->
     Group = call(Sup, group),
@@ -280,7 +237,7 @@ find_call(Sup, Id, Msg) ->
     %% immediately after the tx - we can't be 100% here. So we may as
     %% well dirty_select.
     case mnesia:dirty_select(?TABLE, [{MatchHead, [], ['$1']}]) of
-        [Mirror] -> ?GEN_SERVER:call(Mirror, Msg, infinity);
+        [Mirror] -> call(Mirror, Msg);
         []       -> {error, not_found}
     end.
 
@@ -289,13 +246,16 @@ fold(FunAtom, Sup, AggFun) ->
     lists:foldl(AggFun, [],
                 [apply(?SUPERVISOR, FunAtom, [D]) ||
                     M <- ?PG2:get_members(Group),
-                    D <- [?GEN_SERVER:call(M, delegate_supervisor, infinity)]]).
+                    D <- [delegate(M)]]).
 
 child(Sup, Id) ->
     [Pid] = [Pid || {Id1, Pid, _, _} <- ?SUPERVISOR:which_children(Sup),
                     Id1 =:= Id],
     Pid.
 
+delegate(Sup) -> child(Sup, delegate).
+mirroring(Sup) -> child(Sup, mirroring).
+
 %%----------------------------------------------------------------------------
 
 start_internal(Group, ChildSpecs) ->
@@ -304,24 +264,19 @@ start_internal(Group, ChildSpecs) ->
 
 %%----------------------------------------------------------------------------
 
-init({overall, Group, Init}) ->
-    case Init of
-        {ok, {Restart, ChildSpecs}} ->
-            Delegate = {delegate, {?SUPERVISOR, start_link,
-                                   [?MODULE, {delegate, Restart}]},
-                        temporary, 16#ffffffff, supervisor, [?SUPERVISOR]},
-            Mirroring = {mirroring, {?MODULE, start_internal,
-                                     [Group, ChildSpecs]},
-                         permanent, 16#ffffffff, worker, [?MODULE]},
-            %% Important: Delegate MUST start before Mirroring so that
-            %% when we shut down from above it shuts down last, so
-            %% Mirroring does not see it die.
-            %%
-            %% See comment in handle_info('DOWN', ...) below
-            {ok, {{one_for_all, 0, 1}, [Delegate, Mirroring]}};
-        ignore ->
-            ignore
-    end;
+init({overall, _Group, ignore}) -> ignore;
+init({overall,  Group, {ok, {Restart, ChildSpecs}}}) ->
+    %% Important: Delegate MUST start before Mirroring so that when we
+    %% shut down from above it shuts down last, so Mirroring does not
+    %% see it die.
+    %%
+    %% See comment in handle_info('DOWN', ...) below
+    {ok, {{one_for_all, 0, 1},
+          [{delegate, {?SUPERVISOR, start_link, [?MODULE, {delegate, Restart}]},
+            temporary, 16#ffffffff, supervisor, [?SUPERVISOR]},
+           {mirroring, {?MODULE, start_internal, [Group, ChildSpecs]},
+            permanent, 16#ffffffff, worker, [?MODULE]}]}};
+
 
 init({delegate, Restart}) ->
     {ok, {Restart, []}};
@@ -336,28 +291,29 @@ handle_call({init, Overall}, _From,
                            initial_childspecs = ChildSpecs}) ->
     process_flag(trap_exit, true),
     ?PG2:create(Group),
-    ok = ?PG2:join(Group, self()),
-    Rest = ?PG2:get_members(Group) -- [self()],
+    ok = ?PG2:join(Group, Overall),
+    Rest = ?PG2:get_members(Group) -- [Overall],
     case Rest of
         [] -> {atomic, _} = mnesia:transaction(fun() -> delete_all(Group) end);
         _  -> ok
     end,
     [begin
-         ?GEN_SERVER:cast(Pid, {ensure_monitoring, self()}),
+         ?GEN_SERVER:cast(mirroring(Pid), {ensure_monitoring, Overall}),
          erlang:monitor(process, Pid)
      end || Pid <- Rest],
-    Delegate = child(Overall, delegate),
+    Delegate = delegate(Overall),
     erlang:monitor(process, Delegate),
     State1 = State#state{overall = Overall, delegate = Delegate},
-    case all_started([maybe_start(Group, Delegate, S) || S <- ChildSpecs]) of
-        true  -> {reply, ok, State1};
-        false -> {stop, shutdown, State1}
+    case errors([maybe_start(Group, Overall, Delegate, S) || S <- ChildSpecs]) of
+        []     -> {reply, ok, State1};
+        Errors -> {stop, {shutdown, Errors}, State1}
     end;
 
 handle_call({start_child, ChildSpec}, _From,
-            State = #state{delegate = Delegate,
+            State = #state{overall  = Overall,
+                           delegate = Delegate,
                            group    = Group}) ->
-    {reply, case maybe_start(Group, Delegate, ChildSpec) of
+    {reply, case maybe_start(Group, Overall, Delegate, ChildSpec) of
                 already_in_mnesia        -> {error, already_present};
                 {already_in_mnesia, Pid} -> {error, {already_started, Pid}};
                 Else                     -> Else
@@ -370,9 +326,6 @@ handle_call({delete_child, Id}, _From, State = #state{delegate = Delegate,
 handle_call({msg, F, A}, _From, State = #state{delegate = Delegate}) ->
     {reply, apply(?SUPERVISOR, F, [Delegate | A]), State};
 
-handle_call(delegate_supervisor, _From, State = #state{delegate = Delegate}) ->
-    {reply, Delegate, State};
-
 handle_call(group, _From, State = #state{group = Group}) ->
     {reply, Group, State};
 
@@ -391,7 +344,7 @@ handle_cast(Msg, State) ->
     {stop, {unexpected_cast, Msg}, State}.
 
 handle_info({'DOWN', _Ref, process, Pid, Reason},
-            State = #state{delegate = Pid, group = Group}) ->
+            State = #state{overall = Pid, group = Group}) ->
     %% Since the delegate is temporary, its death won't cause us to
     %% die. Since the overall supervisor kills processes in reverse
     %% order when shutting down "from above" and we started after the
@@ -405,19 +358,20 @@ handle_info({'DOWN', _Ref, process, Pid, Reason},
     {stop, Reason, State};
 
 handle_info({'DOWN', _Ref, process, Pid, _Reason},
-            State = #state{delegate = Delegate, group = Group}) ->
+            State = #state{delegate = Delegate, group = Group,
+                           overall = O}) ->
     %% TODO load balance this
     %% No guarantee pg2 will have received the DOWN before us.
-    Self = self(),
     R = case lists:sort(?PG2:get_members(Group)) -- [Pid] of
-            [Self | _] -> {atomic, ChildSpecs} =
-                              mnesia:transaction(fun() -> update_all(Pid) end),
-                          [start(Delegate, ChildSpec) || ChildSpec <- ChildSpecs];
-            _          -> []
+            [O | _] -> {atomic, ChildSpecs} =
+                           mnesia:transaction(
+                             fun() -> update_all(O, Pid) end),
+                       [start(Delegate, ChildSpec) || ChildSpec <- ChildSpecs];
+            _       -> []
         end,
-    case all_started(R) of
-        true  -> {noreply, State};
-        false -> {stop, shutdown, State}
+    case errors(R) of
+        []     -> {noreply, State};
+        Errors -> {stop, {shutdown, Errors}, State}
     end;
 
 handle_info(Info, State) ->
@@ -432,13 +386,11 @@ code_change(_OldVsn, State, _Extra) ->
 %%----------------------------------------------------------------------------
 
 tell_all_peers_to_die(Group, Reason) ->
-    [?GEN_SERVER:cast(P, {die, Reason}) ||
-        P <- ?PG2:get_members(Group) -- [self()]].
+    [cast(P, {die, Reason}) || P <- ?PG2:get_members(Group) -- [self()]].
 
-maybe_start(Group, Delegate, ChildSpec) ->
-    case mnesia:transaction(fun() ->
-                                    check_start(Group, Delegate, ChildSpec)
-                            end) of
+maybe_start(Group, Overall, Delegate, ChildSpec) ->
+    case mnesia:transaction(
+           fun() -> check_start(Group, Overall, Delegate, ChildSpec) end) of
         {atomic, start}     -> start(Delegate, ChildSpec);
         {atomic, undefined} -> already_in_mnesia;
         {atomic, Pid}       -> {already_in_mnesia, Pid};
@@ -446,31 +398,29 @@ maybe_start(Group, Delegate, ChildSpec) ->
         {aborted, E}        -> {error, E}
     end.
 
-check_start(Group, Delegate, ChildSpec) ->
+check_start(Group, Overall, Delegate, ChildSpec) ->
     case mnesia:wread({?TABLE, {Group, id(ChildSpec)}}) of
-        []  -> write(Group, ChildSpec),
+        []  -> write(Group, Overall, ChildSpec),
                start;
         [S] -> #mirrored_sup_childspec{key           = {Group, Id},
                                        mirroring_pid = Pid} = S,
-               case self() of
+               case Overall of
                    Pid -> child(Delegate, Id);
                    _   -> case supervisor(Pid) of
-                              dead      -> write(Group, ChildSpec),
+                              dead      -> write(Group, Overall, ChildSpec),
                                            start;
                               Delegate0 -> child(Delegate0, Id)
                           end
                end
     end.
 
-supervisor(Pid) ->
-    with_exit_handler(
-      fun() -> dead end,
-      fun() -> gen_server:call(Pid, delegate_supervisor, infinity) end).
+supervisor(Pid) -> with_exit_handler(fun() -> dead end,
+                                     fun() -> delegate(Pid) end).
 
-write(Group, ChildSpec) ->
+write(Group, Overall, ChildSpec) ->
     ok = mnesia:write(
            #mirrored_sup_childspec{key           = {Group, id(ChildSpec)},
-                                   mirroring_pid = self(),
+                                   mirroring_pid = Overall,
                                    childspec     = ChildSpec}),
     ChildSpec.
 
@@ -496,12 +446,12 @@ check_stop(Group, Delegate, Id) ->
 
 id({Id, _, _, _, _, _}) -> Id.
 
-update_all(OldPid) ->
-    MatchHead = #mirrored_sup_childspec{mirroring_pid = OldPid,
+update_all(Overall, OldOverall) ->
+    MatchHead = #mirrored_sup_childspec{mirroring_pid = OldOverall,
                                         key           = '$1',
                                         childspec     = '$2',
                                         _             = '_'},
-    [write(Group, C) ||
+    [write(Group, Overall, C) ||
         [{Group, _Id}, C] <- mnesia:select(?TABLE, [{MatchHead, [], ['$$']}])].
 
 delete_all(Group) ->
@@ -511,12 +461,11 @@ delete_all(Group) ->
     [delete(Group, id(C)) ||
         C <- mnesia:select(?TABLE, [{MatchHead, [], ['$1']}])].
 
-all_started(Results) -> [] =:= [R || R = {error, _} <- Results].
+errors(Results) -> [E || {error, E} <- Results].
 
 %%----------------------------------------------------------------------------
 
-create_tables() ->
-    create_tables([?TABLE_DEF]).
+create_tables() -> create_tables([?TABLE_DEF]).
 
 create_tables([]) ->
     ok;
diff --git a/src/mirrored_supervisor_tests.erl b/src/mirrored_supervisor_tests.erl
index d48a9ca5..f8cbd853 100644
--- a/src/mirrored_supervisor_tests.erl
+++ b/src/mirrored_supervisor_tests.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2011-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(mirrored_supervisor_tests).
@@ -51,7 +51,7 @@ test_migrate() ->
     with_sups(fun([A, _]) ->
                       ?MS:start_child(a, childspec(worker)),
                       Pid1 = pid_of(worker),
-                      kill(A, Pid1),
+                      kill_registered(A, Pid1),
                       Pid2 = pid_of(worker),
                       false = (Pid1 =:= Pid2)
               end, [a, b]).
@@ -61,10 +61,10 @@ test_migrate_twice() ->
     with_sups(fun([A, B]) ->
                       ?MS:start_child(a, childspec(worker)),
                       Pid1 = pid_of(worker),
-                      kill(A, Pid1),
+                      kill_registered(A, Pid1),
                       {ok, C} = start_sup(c),
                       Pid2 = pid_of(worker),
-                      kill(B, Pid2),
+                      kill_registered(B, Pid2),
                       Pid3 = pid_of(worker),
                       false = (Pid1 =:= Pid3),
                       kill(C)
@@ -124,7 +124,7 @@ test_large_group() ->
     with_sups(fun([A, _, _, _]) ->
                       ?MS:start_child(a, childspec(worker)),
                       Pid1 = pid_of(worker),
-                      kill(A, Pid1),
+                      kill_registered(A, Pid1),
                       Pid2 = pid_of(worker),
                       false = (Pid1 =:= Pid2)
               end, [a, b, c, d]).
@@ -134,7 +134,7 @@ test_childspecs_at_init() ->
     S = childspec(worker),
     with_sups(fun([A, _]) ->
                       Pid1 = pid_of(worker),
-                      kill(A, Pid1),
+                      kill_registered(A, Pid1),
                       Pid2 = pid_of(worker),
                       false = (Pid1 =:= Pid2)
               end, [{a, [S]}, {b, [S]}]).
@@ -143,7 +143,7 @@ test_anonymous_supervisors() ->
     with_sups(fun([A, _B]) ->
                       ?MS:start_child(A, childspec(worker)),
                       Pid1 = pid_of(worker),
-                      kill(A, Pid1),
+                      kill_registered(A, Pid1),
                       Pid2 = pid_of(worker),
                       false = (Pid1 =:= Pid2)
               end, [anon, anon]).
@@ -157,7 +157,7 @@ test_no_migration_on_shutdown() ->
     with_sups(fun([Evil, _]) ->
                       ?MS:start_child(Evil, childspec(worker)),
                       try
-                          call(worker, ping),
+                          call(worker, ping, 1000, 100),
                           exit(worker_should_not_have_migrated)
                       catch exit:{timeout_waiting_for_server, _, _} ->
                               ok
@@ -268,7 +268,7 @@ inc_group() ->
 get_group(Group) ->
     {Group, get(counter)}.
 
-call(Id, Msg) -> call(Id, Msg, 1000, 100).
+call(Id, Msg) -> call(Id, Msg, 10*1000, 100).
 
 call(Id, Msg, 0, _Decr) ->
     exit({timeout_waiting_for_server, {Id, Msg}, erlang:get_stacktrace()});
@@ -285,10 +285,16 @@ kill(Pid, Wait) when is_pid(Wait) -> kill(Pid, [Wait]);
 kill(Pid, Waits) ->
     erlang:monitor(process, Pid),
     [erlang:monitor(process, P) || P <- Waits],
-    exit(Pid, kill),
+    exit(Pid, bang),
     kill_wait(Pid),
     [kill_wait(P) || P <- Waits].
 
+kill_registered(Pid, Child) ->
+    {registered_name, Name} = erlang:process_info(Child, registered_name),
+    kill(Pid, Child),
+    false = (Child =:= whereis(Name)),
+    ok.
+
 kill_wait(Pid) ->
     receive
         {'DOWN', _Ref, process, Pid, _Reason} ->
diff --git a/src/mnesia_sync.erl b/src/mnesia_sync.erl
new file mode 100644
index 00000000..a3773d90
--- /dev/null
+++ b/src/mnesia_sync.erl
@@ -0,0 +1,77 @@
+%% The contents of this file are subject to the Mozilla Public License
+%% Version 1.1 (the "License"); you may not use this file except in
+%% compliance with the License. You may obtain a copy of the License
+%% at http://www.mozilla.org/MPL/
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and
+%% limitations under the License.
+%%
+%% The Original Code is RabbitMQ.
+%%
+%% The Initial Developer of the Original Code is VMware, Inc.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
+%%
+
+-module(mnesia_sync).
+
+%% mnesia:sync_transaction/3 fails to guarantee that the log is flushed to disk
+%% at commit. This module is an attempt to minimise the risk of data loss by
+%% performing a coalesced log fsync. Unfortunately this is performed regardless
+%% of whether or not the log was appended to.
+
+-behaviour(gen_server).
+
+-export([sync/0]).
+
+-export([start_link/0, init/1, handle_call/3, handle_cast/2, handle_info/2,
+         terminate/2, code_change/3]).
+
+-define(SERVER, ?MODULE).
+
+-record(state, {waiting, disc_node}).
+
+%%----------------------------------------------------------------------------
+
+-ifdef(use_specs).
+
+-spec(sync/0 :: () -> 'ok').
+
+-endif.
+
+%%----------------------------------------------------------------------------
+
+start_link() ->
+    gen_server:start_link({local, ?SERVER}, ?MODULE, [], []).
+
+sync() ->
+    gen_server:call(?SERVER, sync, infinity).
+
+%%----------------------------------------------------------------------------
+
+init([]) ->
+    {ok, #state{disc_node = mnesia:system_info(use_dir), waiting = []}}.
+
+handle_call(sync, _From, #state{disc_node = false} = State) ->
+    {reply, ok, State};
+handle_call(sync, From, #state{waiting = Waiting} = State) ->
+    {noreply, State#state{waiting = [From | Waiting]}, 0};
+handle_call(Request, _From, State) ->
+    {stop, {unhandled_call, Request}, State}.
+
+handle_cast(Request, State) ->
+    {stop, {unhandled_cast, Request}, State}.
+
+handle_info(timeout, #state{waiting = Waiting} = State) ->
+    ok = disk_log:sync(latest_log),
+    [gen_server:reply(From, ok) || From <- Waiting],
+    {noreply, State#state{waiting = []}};
+handle_info(Message, State) ->
+    {stop, {unhandled_info, Message}, State}.
+
+terminate(_Reason, _State) ->
+    ok.
+
+code_change(_OldVsn, State, _Extra) ->
+    {ok, State}.
diff --git a/src/pg_local.erl b/src/pg_local.erl
index c9c3a3a7..e2e82f1f 100644
--- a/src/pg_local.erl
+++ b/src/pg_local.erl
@@ -13,7 +13,7 @@
 %%    versions of Erlang/OTP. The remaining type specs have been
 %%    removed.
 
-%% All modifications are (C) 2010-2011 VMware, Inc.
+%% All modifications are (C) 2010-2012 VMware, Inc.
 
 %% %CopyrightBegin%
 %% 
diff --git a/src/pmon.erl b/src/pmon.erl
new file mode 100644
index 00000000..45786577
--- /dev/null
+++ b/src/pmon.erl
@@ -0,0 +1,64 @@
+%% The contents of this file are subject to the Mozilla Public License
+%% Version 1.1 (the "License"); you may not use this file except in
+%% compliance with the License. You may obtain a copy of the License
+%% at http://www.mozilla.org/MPL/
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and
+%% limitations under the License.
+%%
+%% The Original Code is RabbitMQ.
+%%
+%% The Initial Developer of the Original Code is VMware, Inc.
+%% Copyright (c) 2011-2012 VMware, Inc.  All rights reserved.
+%%
+
+-module(pmon).
+
+-export([new/0, monitor/2, monitor_all/2, demonitor/2, is_monitored/2, erase/2,
+         monitored/1, is_empty/1]).
+
+-ifdef(use_specs).
+
+%%----------------------------------------------------------------------------
+
+-export_type([?MODULE/0]).
+
+-opaque(?MODULE()    :: dict()).
+
+-spec(new/0          :: () -> ?MODULE()).
+-spec(monitor/2      :: (pid(), ?MODULE()) -> ?MODULE()).
+-spec(monitor_all/2  :: ([pid()], ?MODULE()) -> ?MODULE()).
+-spec(demonitor/2    :: (pid(), ?MODULE()) -> ?MODULE()).
+-spec(is_monitored/2 :: (pid(), ?MODULE()) -> boolean()).
+-spec(erase/2        :: (pid(), ?MODULE()) -> ?MODULE()).
+-spec(monitored/1    :: (?MODULE()) -> [pid()]).
+-spec(is_empty/1     :: (?MODULE()) -> boolean()).
+
+-endif.
+
+new() -> dict:new().
+
+monitor(Pid, M) ->
+    case dict:is_key(Pid, M) of
+        true  -> M;
+        false -> dict:store(Pid, erlang:monitor(process, Pid), M)
+    end.
+
+monitor_all(Pids, M) -> lists:foldl(fun monitor/2, M, Pids).
+
+demonitor(Pid, M) ->
+    case dict:find(Pid, M) of
+        {ok, MRef} -> erlang:demonitor(MRef),
+                      dict:erase(Pid, M);
+        error      -> M
+    end.
+
+is_monitored(Pid, M) -> dict:is_key(Pid, M).
+
+erase(Pid, M) -> dict:erase(Pid, M).
+
+monitored(M) -> dict:fetch_keys(M).
+
+is_empty(M) -> dict:size(M) == 0.
diff --git a/src/priority_queue.erl b/src/priority_queue.erl
index 4fc8b469..780fa2e9 100644
--- a/src/priority_queue.erl
+++ b/src/priority_queue.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 %% Priority queues have essentially the same interface as ordinary
diff --git a/src/rabbit.erl b/src/rabbit.erl
index 0a2681a2..df009529 100644
--- a/src/rabbit.erl
+++ b/src/rabbit.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit).
@@ -45,6 +45,12 @@
                     {requires,    file_handle_cache},
                     {enables,     external_infrastructure}]}).
 
+-rabbit_boot_step({database_sync,
+                   [{description, "database sync"},
+                    {mfa,         {rabbit_sup, start_child, [mnesia_sync]}},
+                    {requires,    database},
+                    {enables,     external_infrastructure}]}).
+
 -rabbit_boot_step({file_handle_cache,
                    [{description, "file handle cache server"},
                     {mfa,         {rabbit_sup, start_restartable_child,
@@ -54,7 +60,8 @@
 
 -rabbit_boot_step({worker_pool,
                    [{description, "worker pool"},
-                    {mfa,         {rabbit_sup, start_child, [worker_pool_sup]}},
+                    {mfa,         {rabbit_sup, start_supervisor_child,
+                                   [worker_pool_sup]}},
                     {requires,    pre_boot},
                     {enables,     external_infrastructure}]}).
 
@@ -132,12 +139,13 @@
 -rabbit_boot_step({recovery,
                    [{description, "exchange, queue and binding recovery"},
                     {mfa,         {rabbit, recover, []}},
-                    {requires,    empty_db_check},
+                    {requires,    core_initialized},
                     {enables,     routing_ready}]}).
 
 -rabbit_boot_step({mirror_queue_slave_sup,
                    [{description, "mirror queue slave sup"},
-                    {mfa,         {rabbit_mirror_queue_slave_sup, start, []}},
+                    {mfa,         {rabbit_sup, start_supervisor_child,
+                                   [rabbit_mirror_queue_slave_sup]}},
                     {requires,    recovery},
                     {enables,     routing_ready}]}).
 
@@ -158,8 +166,9 @@
                     {enables,     networking}]}).
 
 -rabbit_boot_step({direct_client,
-                   [{mfa,        {rabbit_direct, boot, []}},
-                    {requires,   log_relay}]}).
+                   [{description, "direct client"},
+                    {mfa,         {rabbit_direct, boot, []}},
+                    {requires,    log_relay}]}).
 
 -rabbit_boot_step({networking,
                    [{mfa,         {rabbit_networking, boot, []}},
@@ -190,7 +199,7 @@
          rabbit_queue_index, gen, dict, ordsets, file_handle_cache,
          rabbit_msg_store, array, rabbit_msg_store_ets_index, rabbit_msg_file,
          rabbit_exchange_type_fanout, rabbit_exchange_type_topic, mnesia,
-         mnesia_lib, rpc, mnesia_tm, qlc, sofs, proplists]).
+         mnesia_lib, rpc, mnesia_tm, qlc, sofs, proplists, credit_flow, pmon]).
 
 %% HiPE compilation uses multiple cores anyway, but some bits are
 %% IO-bound so we can go faster if we parallelise a bit more. In
@@ -205,14 +214,13 @@
 -type(file_suffix() :: binary()).
 %% this really should be an abstract type
 -type(log_location() :: 'tty' | 'undefined' | file:filename()).
+-type(param() :: atom()).
 
 -spec(maybe_hipe_compile/0 :: () -> 'ok').
 -spec(prepare/0 :: () -> 'ok').
 -spec(start/0 :: () -> 'ok').
 -spec(stop/0 :: () -> 'ok').
 -spec(stop_and_halt/0 :: () -> no_return()).
--spec(rotate_logs/1 :: (file_suffix()) -> rabbit_types:ok_or_error(any())).
--spec(force_event_refresh/0 :: () -> 'ok').
 -spec(status/0 ::
         () -> [{pid, integer()} |
                {running_applications, [{atom(), string(), string()}]} |
@@ -221,12 +229,11 @@
                {memory, any()}]).
 -spec(is_running/0 :: () -> boolean()).
 -spec(is_running/1 :: (node()) -> boolean()).
--spec(environment/0 :: () -> [{atom() | term()}]).
--spec(log_location/1 :: ('sasl' | 'kernel') -> log_location()).
+-spec(environment/0 :: () -> [{param() | term()}]).
+-spec(rotate_logs/1 :: (file_suffix()) -> rabbit_types:ok_or_error(any())).
+-spec(force_event_refresh/0 :: () -> 'ok').
 
--spec(maybe_insert_default_data/0 :: () -> 'ok').
--spec(boot_delegate/0 :: () -> 'ok').
--spec(recover/0 :: () -> 'ok').
+-spec(log_location/1 :: ('sasl' | 'kernel') -> log_location()).
 
 -spec(start/2 :: ('normal',[]) ->
 		      {'error',
@@ -236,6 +243,10 @@
 		      {'ok',pid()}).
 -spec(stop/1 :: (_) -> 'ok').
 
+-spec(maybe_insert_default_data/0 :: () -> 'ok').
+-spec(boot_delegate/0 :: () -> 'ok').
+-spec(recover/0 :: () -> 'ok').
+
 -endif.
 
 %%----------------------------------------------------------------------------
@@ -308,25 +319,37 @@ stop_and_halt() ->
     ok.
 
 status() ->
-    [{pid, list_to_integer(os:getpid())},
-     {running_applications, application:which_applications(infinity)},
-     {os, os:type()},
-     {erlang_version, erlang:system_info(system_version)},
-     {memory, erlang:memory()}] ++
-    rabbit_misc:filter_exit_map(
-        fun ({Key, {M, F, A}}) -> {Key, erlang:apply(M, F, A)} end,
-        [{vm_memory_high_watermark, {vm_memory_monitor,
-                                     get_vm_memory_high_watermark, []}},
-         {vm_memory_limit,          {vm_memory_monitor,
-                                     get_memory_limit, []}}]).
+    S1 = [{pid,                  list_to_integer(os:getpid())},
+          {running_applications, application:which_applications(infinity)},
+          {os,                   os:type()},
+          {erlang_version,       erlang:system_info(system_version)},
+          {memory,               erlang:memory()}],
+    S2 = rabbit_misc:filter_exit_map(
+           fun ({Key, {M, F, A}}) -> {Key, erlang:apply(M, F, A)} end,
+           [{vm_memory_high_watermark, {vm_memory_monitor,
+                                        get_vm_memory_high_watermark, []}},
+            {vm_memory_limit,          {vm_memory_monitor,
+                                        get_memory_limit, []}},
+            {disk_free_limit,          {rabbit_disk_monitor,
+                                        get_disk_free_limit, []}},
+            {disk_free,                {rabbit_disk_monitor,
+                                        get_disk_free, []}}]),
+    S3 = rabbit_misc:with_exit_handler(
+           fun () -> [] end,
+           fun () -> [{file_descriptors, file_handle_cache:info()}] end),
+    S4 = [{processes,        [{limit, erlang:system_info(process_limit)},
+                              {used, erlang:system_info(process_count)}]},
+          {run_queue,        erlang:statistics(run_queue)},
+          {uptime,           begin
+                                 {T,_} = erlang:statistics(wall_clock),
+                                 T div 1000
+                             end}],
+    S1 ++ S2 ++ S3 ++ S4.
 
 is_running() -> is_running(node()).
 
 is_running(Node) ->
-    case rpc:call(Node, application, which_applications, [infinity]) of
-        {badrpc, _} -> false;
-        Apps        -> proplists:is_defined(rabbit, Apps)
-    end.
+    rabbit_nodes:is_running(Node, rabbit).
 
 environment() ->
     lists:keysort(
@@ -348,10 +371,8 @@ rotate_logs(BinarySuffix) ->
 start(normal, []) ->
     case erts_version_check() of
         ok ->
-            ok = rabbit_mnesia:delete_previously_running_nodes(),
             {ok, SupPid} = rabbit_sup:start_link(),
             true = register(rabbit, self()),
-
             print_banner(),
             [ok = run_boot_step(Step) || Step <- boot_steps()],
             io:format("~nbroker running~n"),
@@ -430,8 +451,7 @@ run_boot_step({StepName, Attributes}) ->
             [try
                  apply(M,F,A)
              catch
-                 _:Reason -> boot_error("FAILED~nReason: ~p~nStacktrace: ~p~n",
-                                        [Reason, erlang:get_stacktrace()])
+                 _:Reason -> boot_step_error(Reason, erlang:get_stacktrace())
              end || {M,F,A} <- MFAs],
             io:format("done~n"),
             ok
@@ -490,8 +510,27 @@ sort_boot_steps(UnsortedSteps) ->
                end])
     end.
 
+boot_step_error({error, {timeout_waiting_for_tables, _}}, _Stacktrace) ->
+    {Err, Nodes} =
+        case rabbit_mnesia:read_previously_running_nodes() of
+            [] -> {"Timeout contacting cluster nodes. Since RabbitMQ was"
+                   " shut down forcefully~nit cannot determine which nodes"
+                   " are timing out. Details on all nodes will~nfollow.~n",
+                   rabbit_mnesia:all_clustered_nodes() -- [node()]};
+            Ns -> {rabbit_misc:format(
+                     "Timeout contacting cluster nodes: ~p.~n", [Ns]),
+                   Ns}
+        end,
+    boot_error(Err ++ rabbit_nodes:diagnostics(Nodes) ++ "~n~n", []);
+
+boot_step_error(Reason, Stacktrace) ->
+    boot_error("Error description:~n   ~p~n~n"
+               "Log files (may contain more information):~n   ~s~n   ~s~n~n"
+               "Stack trace:~n   ~p~n~n",
+               [Reason, log_location(kernel), log_location(sasl), Stacktrace]).
+
 boot_error(Format, Args) ->
-    io:format("BOOT ERROR: " ++ Format, Args),
+    io:format("~n~nBOOT FAILED~n===========~n~n" ++ Format, Args),
     error_logger:error_msg(Format, Args),
     timer:sleep(1000),
     exit({?MODULE, failure_during_boot}).
@@ -501,7 +540,7 @@ boot_error(Format, Args) ->
 
 boot_delegate() ->
     {ok, Count} = application:get_env(rabbit, delegate_count),
-    rabbit_sup:start_child(delegate_sup, [Count]).
+    rabbit_sup:start_supervisor_child(delegate_sup, [Count]).
 
 recover() ->
     rabbit_binding:recover(rabbit_exchange:recover(), rabbit_amqqueue:start()).
@@ -584,15 +623,12 @@ log_location(Type) ->
 rotate_logs(File, Suffix, Handler) ->
     rotate_logs(File, Suffix, Handler, Handler).
 
-rotate_logs(File, Suffix, OldHandler, NewHandler) ->
-    case File of
-        undefined -> ok;
-        tty       -> ok;
-        _         -> gen_event:swap_handler(
-                       error_logger,
-                       {OldHandler, swap},
-                       {NewHandler, {File, Suffix}})
-    end.
+rotate_logs(undefined, _Suffix, _OldHandler, _NewHandler) -> ok;
+rotate_logs(tty,       _Suffix, _OldHandler, _NewHandler) -> ok;
+rotate_logs(File,       Suffix,  OldHandler,  NewHandler) ->
+    gen_event:swap_handler(error_logger,
+                           {OldHandler, swap},
+                           {NewHandler, {File, Suffix}}).
 
 log_rotation_result({error, MainLogError}, {error, SaslLogError}) ->
     {error, {{cannot_rotate_main_logs, MainLogError},
@@ -645,7 +681,7 @@ print_banner() ->
                 {"app descriptor", app_location()},
                 {"home dir",       home_dir()},
                 {"config file(s)", config_files()},
-                {"cookie hash",    rabbit_misc:cookie_hash()},
+                {"cookie hash",    rabbit_nodes:cookie_hash()},
                 {"log",            log_location(kernel)},
                 {"sasl log",       log_location(sasl)},
                 {"database dir",   rabbit_mnesia:dir()},
@@ -678,6 +714,6 @@ config_files() ->
     case init:get_argument(config) of
         {ok, Files} -> [filename:absname(
                           filename:rootname(File, ".config") ++ ".config") ||
-                           File <- Files];
+                           [File] <- Files];
         error       -> []
     end.
diff --git a/src/rabbit_access_control.erl b/src/rabbit_access_control.erl
index ca28d686..75c53511 100644
--- a/src/rabbit_access_control.erl
+++ b/src/rabbit_access_control.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_access_control).
@@ -66,7 +66,6 @@ check_user_login(Username, AuthProps) ->
 
 check_vhost_access(User = #user{ username     = Username,
                                  auth_backend = Module }, VHostPath) ->
-    ?LOGDEBUG("Checking VHost access for ~p to ~p~n", [Username, VHostPath]),
     check_access(
       fun() ->
               rabbit_vhost:exists(VHostPath) andalso
diff --git a/src/rabbit_alarm.erl b/src/rabbit_alarm.erl
index fd03ca85..04e0c141 100644
--- a/src/rabbit_alarm.erl
+++ b/src/rabbit_alarm.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_alarm).
@@ -23,7 +23,7 @@
 -export([init/1, handle_call/2, handle_event/2, handle_info/2,
          terminate/2, code_change/3]).
 
--export([remote_conserve_memory/2]). %% Internal use only
+-export([remote_conserve_resources/3]). %% Internal use only
 
 -record(alarms, {alertees, alarmed_nodes}).
 
@@ -31,10 +31,9 @@
 
 -ifdef(use_specs).
 
--type(mfa_tuple() :: {atom(), atom(), list()}).
 -spec(start/0 :: () -> 'ok').
 -spec(stop/0 :: () -> 'ok').
--spec(register/2 :: (pid(), mfa_tuple()) -> boolean()).
+-spec(register/2 :: (pid(), rabbit_types:mfargs()) -> boolean()).
 -spec(on_node_up/1 :: (node()) -> 'ok').
 -spec(on_node_down/1 :: (node()) -> 'ok').
 
@@ -46,6 +45,9 @@ start() ->
     ok = alarm_handler:add_alarm_handler(?MODULE, []),
     {ok, MemoryWatermark} = application:get_env(vm_memory_high_watermark),
     rabbit_sup:start_restartable_child(vm_memory_monitor, [MemoryWatermark]),
+
+    {ok, DiskLimit} = application:get_env(disk_free_limit),
+    rabbit_sup:start_restartable_child(rabbit_disk_monitor, [DiskLimit]),
     ok.
 
 stop() ->
@@ -62,41 +64,41 @@ on_node_down(Node) -> gen_event:notify(alarm_handler, {node_down, Node}).
 
 %% Can't use alarm_handler:{set,clear}_alarm because that doesn't
 %% permit notifying a remote node.
-remote_conserve_memory(Pid, true) ->
+remote_conserve_resources(Pid, Source, true) ->
     gen_event:notify({alarm_handler, node(Pid)},
-                     {set_alarm, {{vm_memory_high_watermark, node()}, []}});
-remote_conserve_memory(Pid, false) ->
+                     {set_alarm, {{resource_limit, Source, node()}, []}});
+remote_conserve_resources(Pid, Source, false) ->
     gen_event:notify({alarm_handler, node(Pid)},
-                     {clear_alarm, {vm_memory_high_watermark, node()}}).
+                     {clear_alarm, {resource_limit, Source, node()}}).
 
 %%----------------------------------------------------------------------------
 
 init([]) ->
     {ok, #alarms{alertees      = dict:new(),
-                 alarmed_nodes = sets:new()}}.
+                 alarmed_nodes = dict:new()}}.
 
 handle_call({register, Pid, HighMemMFA}, State) ->
-    {ok, 0 < sets:size(State#alarms.alarmed_nodes),
+    {ok, 0 < dict:size(State#alarms.alarmed_nodes),
      internal_register(Pid, HighMemMFA, State)};
 
 handle_call(_Request, State) ->
     {ok, not_understood, State}.
 
-handle_event({set_alarm, {{vm_memory_high_watermark, Node}, []}}, State) ->
-    {ok, maybe_alert(fun sets:add_element/2, Node, State)};
+handle_event({set_alarm, {{resource_limit, Source, Node}, []}}, State) ->
+    {ok, maybe_alert(fun dict:append/3, Node, Source, State)};
 
-handle_event({clear_alarm, {vm_memory_high_watermark, Node}}, State) ->
-    {ok, maybe_alert(fun sets:del_element/2, Node, State)};
+handle_event({clear_alarm, {resource_limit, Source, Node}}, State) ->
+    {ok, maybe_alert(fun dict_unappend/3, Node, Source, State)};
 
 handle_event({node_up, Node}, State) ->
     %% Must do this via notify and not call to avoid possible deadlock.
     ok = gen_event:notify(
            {alarm_handler, Node},
-           {register, self(), {?MODULE, remote_conserve_memory, []}}),
+           {register, self(), {?MODULE, remote_conserve_resources, []}}),
     {ok, State};
 
 handle_event({node_down, Node}, State) ->
-    {ok, maybe_alert(fun sets:del_element/2, Node, State)};
+    {ok, maybe_alert(fun dict_unappend_all/3, Node, [], State)};
 
 handle_event({register, Pid, HighMemMFA}, State) ->
     {ok, internal_register(Pid, HighMemMFA, State)};
@@ -119,34 +121,58 @@ code_change(_OldVsn, State, _Extra) ->
 
 %%----------------------------------------------------------------------------
 
-maybe_alert(SetFun, Node, State = #alarms{alarmed_nodes = AN,
-                                          alertees      = Alertees}) ->
-    AN1 = SetFun(Node, AN),
-    BeforeSz = sets:size(AN),
-    AfterSz  = sets:size(AN1),
+dict_unappend_all(Key, _Val, Dict) ->
+    dict:erase(Key, Dict).
+
+dict_unappend(Key, Val, Dict) ->
+    case lists:delete(Val, dict:fetch(Key, Dict)) of
+        [] -> dict:erase(Key, Dict);
+        X  -> dict:store(Key, X, Dict)
+    end.
+
+count_dict_values(Val, Dict) ->
+    dict:fold(fun (_Node, List, Count) ->
+                  Count + case lists:member(Val, List) of
+                              true  -> 1;
+                              false -> 0
+                          end
+              end, 0, Dict).
+
+maybe_alert(UpdateFun, Node, Source,
+            State = #alarms{alarmed_nodes = AN,
+                            alertees      = Alertees}) ->
+    AN1 = UpdateFun(Node, Source, AN),
+    BeforeSz = count_dict_values(Source, AN),
+    AfterSz  = count_dict_values(Source, AN1),
+
     %% If we have changed our alarm state, inform the remotes.
     IsLocal = Node =:= node(),
-    if IsLocal andalso BeforeSz < AfterSz -> ok = alert_remote(true,  Alertees);
-       IsLocal andalso BeforeSz > AfterSz -> ok = alert_remote(false, Alertees);
-       true                               -> ok
+    if IsLocal andalso BeforeSz < AfterSz ->
+           ok = alert_remote(true,  Alertees, Source);
+       IsLocal andalso BeforeSz > AfterSz ->
+           ok = alert_remote(false, Alertees, Source);
+       true                               ->
+           ok
     end,
     %% If the overall alarm state has changed, inform the locals.
-    case {BeforeSz, AfterSz} of
-        {0, 1} -> ok = alert_local(true,  Alertees);
-        {1, 0} -> ok = alert_local(false, Alertees);
+    case {dict:size(AN), dict:size(AN1)} of
+        {0, 1} -> ok = alert_local(true,  Alertees, Source);
+        {1, 0} -> ok = alert_local(false, Alertees, Source);
         {_, _} -> ok
     end,
     State#alarms{alarmed_nodes = AN1}.
 
-alert_local(Alert, Alertees)  -> alert(Alert, Alertees, fun erlang:'=:='/2).
+alert_local(Alert, Alertees, _Source) ->
+    alert(Alertees, [Alert], fun erlang:'=:='/2).
 
-alert_remote(Alert, Alertees) -> alert(Alert, Alertees, fun erlang:'=/='/2).
+alert_remote(Alert, Alertees, Source) ->
+    alert(Alertees, [Source, Alert], fun erlang:'=/='/2).
 
-alert(Alert, Alertees, NodeComparator) ->
+alert(Alertees, AlertArg, NodeComparator) ->
     Node = node(),
     dict:fold(fun (Pid, {M, F, A}, ok) ->
                       case NodeComparator(Node, node(Pid)) of
-                          true  -> apply(M, F, A ++ [Pid, Alert]);
+                          true  -> apply(M, F, A ++ [Pid] ++ AlertArg);
                           false -> ok
                       end
               end, ok, Alertees).
@@ -154,9 +180,9 @@ alert(Alert, Alertees, NodeComparator) ->
 internal_register(Pid, {M, F, A} = HighMemMFA,
                   State = #alarms{alertees = Alertees}) ->
     _MRef = erlang:monitor(process, Pid),
-    case sets:is_element(node(), State#alarms.alarmed_nodes) of
-        true  -> ok = apply(M, F, A ++ [Pid, true]);
-        false -> ok
+    case dict:find(node(), State#alarms.alarmed_nodes) of
+        {ok, _Sources} -> apply(M, F, A ++ [Pid, true]);
+        error          -> ok
     end,
     NewAlertees = dict:store(Pid, HighMemMFA, Alertees),
     State#alarms{alertees = NewAlertees}.
diff --git a/src/rabbit_amqqueue.erl b/src/rabbit_amqqueue.erl
index 96017df8..c1673504 100644
--- a/src/rabbit_amqqueue.erl
+++ b/src/rabbit_amqqueue.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_amqqueue).
@@ -20,19 +20,19 @@
 -export([pseudo_queue/2]).
 -export([lookup/1, with/2, with_or_die/2, assert_equivalence/5,
          check_exclusive_access/2, with_exclusive_access_or_die/3,
-         stat/1, deliver/2, requeue/3, ack/3, reject/4]).
+         stat/1, deliver/2, deliver_flow/2, requeue/3, ack/3, reject/4]).
 -export([list/0, list/1, info_keys/0, info/1, info/2, info_all/1, info_all/2]).
 -export([force_event_refresh/0]).
 -export([consumers/1, consumers_all/1, consumer_info_keys/0]).
 -export([basic_get/3, basic_consume/7, basic_cancel/4]).
--export([notify_sent/2, unblock/2, flush_all/2]).
+-export([notify_sent/2, notify_sent_queue_down/1, unblock/2, flush_all/2]).
 -export([notify_down_all/2, limit_all/3]).
 -export([on_node_down/1]).
 -export([store_queue/1]).
 
 
 %% internal
--export([internal_declare/2, internal_delete/1, run_backing_queue/3,
+-export([internal_declare/2, internal_delete/2, run_backing_queue/3,
          set_ram_duration_target/2, set_maximum_since_use/2]).
 
 -include("rabbit.hrl").
@@ -40,21 +40,25 @@
 
 -define(INTEGER_ARG_TYPES, [byte, short, signedint, long]).
 
+-define(MORE_CONSUMER_CREDIT_AFTER, 50).
+
+-define(FAILOVER_WAIT_MILLIS, 100).
+
 %%----------------------------------------------------------------------------
 
 -ifdef(use_specs).
 
--export_type([name/0, qmsg/0]).
+-export_type([name/0, qmsg/0, routing_result/0]).
 
 -type(name() :: rabbit_types:r('queue')).
-
+-type(qpids() :: [pid()]).
 -type(qlen() :: rabbit_types:ok(non_neg_integer())).
 -type(qfun(A) :: fun ((rabbit_types:amqqueue()) -> A | no_return())).
 -type(qmsg() :: {name(), pid(), msg_id(), boolean(), rabbit_types:message()}).
 -type(msg_id() :: non_neg_integer()).
 -type(ok_or_errors() ::
         'ok' | {'error', [{'error' | 'exit' | 'throw', any()}]}).
-
+-type(routing_result() :: 'routed' | 'unroutable' | 'not_delivered').
 -type(queue_or_not_found() :: rabbit_types:amqqueue() | 'not_found').
 
 -spec(start/0 :: () -> [name()]).
@@ -69,7 +73,8 @@
         -> queue_or_not_found() | rabbit_misc:thunk(queue_or_not_found())).
 -spec(lookup/1 ::
         (name()) -> rabbit_types:ok(rabbit_types:amqqueue()) |
-                    rabbit_types:error('not_found')).
+                    rabbit_types:error('not_found');
+        ([name()]) -> [rabbit_types:amqqueue()]).
 -spec(with/2 :: (name(), qfun(A)) -> A | rabbit_types:error('not_found')).
 -spec(with_or_die/2 ::
         (name(), qfun(A)) -> A | rabbit_types:channel_exit()).
@@ -104,7 +109,7 @@
 -spec(stat/1 ::
         (rabbit_types:amqqueue())
         -> {'ok', non_neg_integer(), non_neg_integer()}).
--spec(delete_immediately/1 :: (rabbit_types:amqqueue()) -> 'ok').
+-spec(delete_immediately/1 :: (qpids()) -> 'ok').
 -spec(delete/3 ::
         (rabbit_types:amqqueue(), 'false', 'false')
         -> qlen();
@@ -117,12 +122,15 @@
            rabbit_types:error('in_use') |
            rabbit_types:error('not_empty')).
 -spec(purge/1 :: (rabbit_types:amqqueue()) -> qlen()).
--spec(deliver/2 :: (pid(), rabbit_types:delivery()) -> boolean()).
+-spec(deliver/2 :: ([rabbit_types:amqqueue()], rabbit_types:delivery()) ->
+                        {routing_result(), qpids()}).
+-spec(deliver_flow/2 :: ([rabbit_types:amqqueue()], rabbit_types:delivery()) ->
+                             {routing_result(), qpids()}).
 -spec(requeue/3 :: (pid(), [msg_id()],  pid()) -> 'ok').
 -spec(ack/3 :: (pid(), [msg_id()], pid()) -> 'ok').
 -spec(reject/4 :: (pid(), [msg_id()], boolean(), pid()) -> 'ok').
--spec(notify_down_all/2 :: ([pid()], pid()) -> ok_or_errors()).
--spec(limit_all/3 :: ([pid()], pid(), rabbit_limiter:token()) ->
+-spec(notify_down_all/2 :: (qpids(), pid()) -> ok_or_errors()).
+-spec(limit_all/3 :: (qpids(), pid(), rabbit_limiter:token()) ->
                           ok_or_errors()).
 -spec(basic_get/3 :: (rabbit_types:amqqueue(), pid(), boolean()) ->
                           {'ok', non_neg_integer(), qmsg()} | 'empty').
@@ -133,13 +141,14 @@
 -spec(basic_cancel/4 ::
         (rabbit_types:amqqueue(), pid(), rabbit_types:ctag(), any()) -> 'ok').
 -spec(notify_sent/2 :: (pid(), pid()) -> 'ok').
+-spec(notify_sent_queue_down/1 :: (pid()) -> 'ok').
 -spec(unblock/2 :: (pid(), pid()) -> 'ok').
--spec(flush_all/2 :: ([pid()], pid()) -> 'ok').
--spec(internal_delete/1 ::
-        (name()) -> rabbit_types:ok_or_error('not_found') |
-                    rabbit_types:connection_exit() |
-                    fun (() -> rabbit_types:ok_or_error('not_found') |
-                               rabbit_types:connection_exit())).
+-spec(flush_all/2 :: (qpids(), pid()) -> 'ok').
+-spec(internal_delete/2 ::
+        (name(), pid()) -> rabbit_types:ok_or_error('not_found') |
+                           rabbit_types:connection_exit() |
+                           fun (() -> rabbit_types:ok_or_error('not_found') |
+                                      rabbit_types:connection_exit())).
 -spec(run_backing_queue/3 ::
         (pid(), atom(),
          (fun ((atom(), A) -> {[rabbit_types:msg_id()], A}))) -> 'ok').
@@ -222,7 +231,7 @@ internal_declare(Q = #amqqueue{name = QueueName}, false) ->
                   [ExistingQ = #amqqueue{pid = QPid}] ->
                       case rabbit_misc:is_process_alive(QPid) of
                           true  -> rabbit_misc:const(ExistingQ);
-                          false -> TailFun = internal_delete(QueueName),
+                          false -> TailFun = internal_delete(QueueName, QPid),
                                    fun () -> TailFun(), ExistingQ end
                       end
               end
@@ -264,6 +273,10 @@ add_default_binding(#amqqueue{name = QueueName}) ->
                                 key         = RoutingKey,
                                 args        = []}).
 
+lookup(Names) when is_list(Names) ->
+    %% Normally we'd call mnesia:dirty_read/1 here, but that is quite
+    %% expensive for reasons explained in rabbit_misc:dirty_read/1.
+    lists:append([ets:lookup(rabbit_queue, Name) || Name <- Names]);
 lookup(Name) ->
     rabbit_misc:dirty_read({rabbit_queue, Name}).
 
@@ -317,33 +330,60 @@ assert_args_equivalence(#amqqueue{name = QueueName, arguments = Args},
       [<<"x-expires">>, <<"x-message-ttl">>, <<"x-ha-policy">>]).
 
 check_declare_arguments(QueueName, Args) ->
-    [case Fun(rabbit_misc:table_lookup(Args, Key), Args) of
-         ok             -> ok;
-         {error, Error} -> rabbit_misc:protocol_error(
-                             precondition_failed,
-                             "invalid arg '~s' for ~s: ~255p",
-                             [Key, rabbit_misc:rs(QueueName), Error])
-     end || {Key, Fun} <-
-                [{<<"x-expires">>,     fun check_integer_argument/2},
-                 {<<"x-message-ttl">>, fun check_integer_argument/2},
-                 {<<"x-ha-policy">>,   fun check_ha_policy_argument/2}]],
+    Checks = [{<<"x-expires">>,                 fun check_positive_int_arg/2},
+              {<<"x-message-ttl">>,             fun check_non_neg_int_arg/2},
+              {<<"x-ha-policy">>,               fun check_ha_policy_arg/2},
+              {<<"x-dead-letter-exchange">>,    fun check_string_arg/2},
+              {<<"x-dead-letter-routing-key">>, fun check_dlxrk_arg/2}],
+    [case rabbit_misc:table_lookup(Args, Key) of
+         undefined -> ok;
+         TypeVal   -> case Fun(TypeVal, Args) of
+                          ok             -> ok;
+                          {error, Error} -> rabbit_misc:protocol_error(
+                                              precondition_failed,
+                                              "invalid arg '~s' for ~s: ~255p",
+                                              [Key, rabbit_misc:rs(QueueName),
+                                               Error])
+                      end
+     end || {Key, Fun} <- Checks],
     ok.
 
-check_integer_argument(undefined, _Args) ->
+check_string_arg({longstr, _}, _Args) ->
     ok;
-check_integer_argument({Type, Val}, _Args) when Val > 0 ->
+check_string_arg({Type, _}, _) ->
+    {error, {unacceptable_type, Type}}.
+
+check_int_arg({Type, _}, _) ->
     case lists:member(Type, ?INTEGER_ARG_TYPES) of
         true  -> ok;
         false -> {error, {unacceptable_type, Type}}
+    end.
+
+check_positive_int_arg({Type, Val}, Args) ->
+    case check_int_arg({Type, Val}, Args) of
+        ok when Val > 0 -> ok;
+        ok              -> {error, {value_zero_or_less, Val}};
+        Error           -> Error
+    end.
+
+check_non_neg_int_arg({Type, Val}, Args) ->
+    case check_int_arg({Type, Val}, Args) of
+        ok when Val >= 0 -> ok;
+        ok               -> {error, {value_less_than_zero, Val}};
+        Error            -> Error
+    end.
+
+check_dlxrk_arg({longstr, _}, Args) ->
+    case rabbit_misc:table_lookup(Args, <<"x-dead-letter-exchange">>) of
+        undefined -> {error, routing_key_but_no_dlx_defined};
+        _         -> ok
     end;
-check_integer_argument({_Type, Val}, _Args) ->
-    {error, {value_zero_or_less, Val}}.
+check_dlxrk_arg({Type, _}, _Args) ->
+    {error, {unacceptable_type, Type}}.
 
-check_ha_policy_argument(undefined, _Args) ->
-    ok;
-check_ha_policy_argument({longstr, <<"all">>}, _Args) ->
+check_ha_policy_arg({longstr, <<"all">>}, _Args) ->
     ok;
-check_ha_policy_argument({longstr, <<"nodes">>}, Args) ->
+check_ha_policy_arg({longstr, <<"nodes">>}, Args) ->
     case rabbit_misc:table_lookup(Args, <<"x-ha-policy-params">>) of
         undefined ->
             {error, {require, 'x-ha-policy-params'}};
@@ -359,9 +399,9 @@ check_ha_policy_argument({longstr, <<"nodes">>}, Args) ->
         {Type, _} ->
             {error, {ha_nodes_policy_params_not_array_of_longstr, Type}}
     end;
-check_ha_policy_argument({longstr, Policy}, _Args) ->
+check_ha_policy_arg({longstr, Policy}, _Args) ->
     {error, {invalid_ha_policy, Policy}};
-check_ha_policy_argument({Type, _}, _Args) ->
+check_ha_policy_arg({Type, _}, _Args) ->
     {error, {unacceptable_type, Type}}.
 
 list() ->
@@ -389,9 +429,26 @@ info_all(VHostPath) -> map(VHostPath, fun (Q) -> info(Q) end).
 
 info_all(VHostPath, Items) -> map(VHostPath, fun (Q) -> info(Q, Items) end).
 
+%% We need to account for the idea that queues may be mid-promotion
+%% during force_event_refresh (since it's likely we're doing this in
+%% the first place since a node failed). Therefore we keep poking at
+%% the list of queues until we were able to talk to a live process or
+%% the queue no longer exists.
 force_event_refresh() ->
-    [gen_server2:cast(Q#amqqueue.pid, force_event_refresh) || Q <- list()],
-    ok.
+    force_event_refresh([Q#amqqueue.name || Q <- list()]).
+
+force_event_refresh(QNames) ->
+    Qs = [Q || Q <- list(), lists:member(Q#amqqueue.name, QNames)],
+    {_, Bad} = rabbit_misc:multi_call(
+                 [Q#amqqueue.pid || Q <- Qs], force_event_refresh),
+    FailedPids = [Pid || {Pid, _Reason} <- Bad],
+    Failed = [Name || #amqqueue{name = Name, pid = Pid} <- Qs,
+                      lists:member(Pid, FailedPids)],
+    case Failed of
+        [] -> ok;
+        _  -> timer:sleep(?FAILOVER_WAIT_MILLIS),
+              force_event_refresh(Failed)
+    end.
 
 consumers(#amqqueue{ pid = QPid }) ->
     delegate_call(QPid, consumers).
@@ -411,22 +468,18 @@ consumers_all(VHostPath) ->
 stat(#amqqueue{pid = QPid}) ->
     delegate_call(QPid, stat).
 
-delete_immediately(#amqqueue{ pid = QPid }) ->
-    gen_server2:cast(QPid, delete_immediately).
+delete_immediately(QPids) ->
+    [gen_server2:cast(QPid, delete_immediately) || QPid <- QPids],
+    ok.
 
 delete(#amqqueue{ pid = QPid }, IfUnused, IfEmpty) ->
     delegate_call(QPid, {delete, IfUnused, IfEmpty}).
 
 purge(#amqqueue{ pid = QPid }) -> delegate_call(QPid, purge).
 
-deliver(QPid, Delivery = #delivery{immediate = true}) ->
-    gen_server2:call(QPid, {deliver_immediately, Delivery}, infinity);
-deliver(QPid, Delivery = #delivery{mandatory = true}) ->
-    gen_server2:call(QPid, {deliver, Delivery}, infinity),
-    true;
-deliver(QPid, Delivery) ->
-    gen_server2:cast(QPid, {deliver, Delivery}),
-    true.
+deliver(Qs, Delivery) -> deliver(Qs, Delivery, noflow).
+
+deliver_flow(Qs, Delivery) -> deliver(Qs, Delivery, flow).
 
 requeue(QPid, MsgIds, ChPid) ->
     delegate_call(QPid, {requeue, MsgIds, ChPid}).
@@ -458,7 +511,21 @@ basic_cancel(#amqqueue{pid = QPid}, ChPid, ConsumerTag, OkMsg) ->
     ok = delegate_call(QPid, {basic_cancel, ChPid, ConsumerTag, OkMsg}).
 
 notify_sent(QPid, ChPid) ->
-    gen_server2:cast(QPid, {notify_sent, ChPid}).
+    Key = {consumer_credit_to, QPid},
+    put(Key, case get(Key) of
+                 1         -> gen_server2:cast(
+                                QPid, {notify_sent, ChPid,
+                                       ?MORE_CONSUMER_CREDIT_AFTER}),
+                              ?MORE_CONSUMER_CREDIT_AFTER;
+                 undefined -> erlang:monitor(process, QPid),
+                              ?MORE_CONSUMER_CREDIT_AFTER - 1;
+                 C         -> C - 1
+             end),
+    ok.
+
+notify_sent_queue_down(QPid) ->
+    erase({consumer_credit_to, QPid}),
+    ok.
 
 unblock(QPid, ChPid) ->
     delegate_cast(QPid, {unblock, ChPid}).
@@ -474,13 +541,19 @@ internal_delete1(QueueName) ->
     %% after the transaction.
     rabbit_binding:remove_for_destination(QueueName).
 
-internal_delete(QueueName) ->
+internal_delete(QueueName, QPid) ->
     rabbit_misc:execute_mnesia_tx_with_tail(
       fun () ->
               case mnesia:wread({rabbit_queue, QueueName}) of
                   []  -> rabbit_misc:const({error, not_found});
                   [_] -> Deletions = internal_delete1(QueueName),
-                         rabbit_binding:process_deletions(Deletions)
+                         T = rabbit_binding:process_deletions(Deletions),
+                         fun() ->
+                                 ok = T(),
+                                 ok = rabbit_event:notify(queue_deleted,
+                                                          [{pid,  QPid},
+                                                           {name, QueueName}])
+                         end
               end
       end).
 
@@ -495,14 +568,25 @@ set_maximum_since_use(QPid, Age) ->
 
 on_node_down(Node) ->
     rabbit_misc:execute_mnesia_tx_with_tail(
-      fun () -> Dels = qlc:e(qlc:q([delete_queue(QueueName) ||
-                                       #amqqueue{name = QueueName, pid = Pid,
-                                                 slave_pids = []}
-                                           <- mnesia:table(rabbit_queue),
-                                       node(Pid) == Node])),
-                rabbit_binding:process_deletions(
-                  lists:foldl(fun rabbit_binding:combine_deletions/2,
-                              rabbit_binding:new_deletions(), Dels))
+      fun () -> QsDels =
+                    qlc:e(qlc:q([{{QName, Pid}, delete_queue(QName)} ||
+                                    #amqqueue{name = QName, pid = Pid,
+                                              slave_pids = []}
+                                        <- mnesia:table(rabbit_queue),
+                                    node(Pid) == Node])),
+                {Qs, Dels} = lists:unzip(QsDels),
+                T = rabbit_binding:process_deletions(
+                      lists:foldl(fun rabbit_binding:combine_deletions/2,
+                                  rabbit_binding:new_deletions(), Dels)),
+                fun () ->
+                        T(),
+                        lists:foreach(
+                          fun({QName, QPid}) ->
+                                  ok = rabbit_event:notify(queue_deleted,
+                                                           [{pid,  QPid},
+                                                            {name, QName}])
+                          end, Qs)
+                end
       end).
 
 delete_queue(QueueName) ->
@@ -518,6 +602,49 @@ pseudo_queue(QueueName, Pid) ->
               slave_pids   = [],
               mirror_nodes = undefined}.
 
+deliver([], #delivery{mandatory = false, immediate = false}, _Flow) ->
+    %% /dev/null optimisation
+    {routed, []};
+
+deliver(Qs, Delivery = #delivery{mandatory = false, immediate = false}, Flow) ->
+    %% optimisation: when Mandatory = false and Immediate = false,
+    %% rabbit_amqqueue:deliver will deliver the message to the queue
+    %% process asynchronously, and return true, which means all the
+    %% QPids will always be returned. It is therefore safe to use a
+    %% fire-and-forget cast here and return the QPids - the semantics
+    %% is preserved. This scales much better than the non-immediate
+    %% case below.
+    QPids = qpids(Qs),
+    case Flow of
+        flow   -> [credit_flow:send(QPid) || QPid <- QPids];
+        noflow -> ok
+    end,
+    delegate:invoke_no_result(
+      QPids, fun (QPid) ->
+                     gen_server2:cast(QPid, {deliver, Delivery, Flow})
+             end),
+    {routed, QPids};
+
+deliver(Qs, Delivery = #delivery{mandatory = Mandatory, immediate = Immediate},
+        _Flow) ->
+    QPids = qpids(Qs),
+    {Success, _} =
+        delegate:invoke(
+          QPids, fun (QPid) ->
+                         gen_server2:call(QPid, {deliver, Delivery}, infinity)
+                 end),
+    case {Mandatory, Immediate,
+          lists:foldl(fun ({QPid, true}, {_, H}) -> {true, [QPid | H]};
+                          ({_,   false}, {_, H}) -> {true, H}
+                      end, {false, []}, Success)} of
+        {true, _   , {false, []}} -> {unroutable,    []};
+        {_   , true, {_    , []}} -> {not_delivered, []};
+        {_   , _   , {_    ,  R}} -> {routed,         R}
+    end.
+
+qpids(Qs) -> lists:append([[QPid | SPids] ||
+                              #amqqueue{pid = QPid, slave_pids = SPids} <- Qs]).
+
 safe_delegate_call_ok(F, Pids) ->
     case delegate:invoke(Pids, fun (Pid) ->
                                        rabbit_misc:with_exit_handler(
diff --git a/src/rabbit_amqqueue_process.erl b/src/rabbit_amqqueue_process.erl
index ba20b355..5701efeb 100644
--- a/src/rabbit_amqqueue_process.erl
+++ b/src/rabbit_amqqueue_process.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_amqqueue_process).
@@ -20,16 +20,13 @@
 
 -behaviour(gen_server2).
 
--define(UNSENT_MESSAGE_LIMIT,          100).
+-define(UNSENT_MESSAGE_LIMIT,          200).
 -define(SYNC_INTERVAL,                 25). %% milliseconds
 -define(RAM_DURATION_UPDATE_INTERVAL,  5000).
 
--define(BASE_MESSAGE_PROPERTIES,
-        #message_properties{expiry = undefined, needs_confirming = false}).
-
 -export([start_link/1, info_keys/0]).
 
--export([init_with_backing_queue_state/7]).
+-export([init_with_backing_queue_state/8]).
 
 -export([init/1, terminate/2, code_change/3, handle_call/3, handle_cast/2,
          handle_info/2, handle_pre_hibernate/1, prioritise_call/3,
@@ -49,7 +46,14 @@
             stats_timer,
             msg_id_to_channel,
             ttl,
-            ttl_timer_ref
+            ttl_timer_ref,
+            senders,
+            publish_seqno,
+            unconfirmed,
+            delayed_stop,
+            queue_monitors,
+            dlx,
+            dlx_routing_key
            }).
 
 -record(consumer, {tag, ack_required}).
@@ -71,9 +75,9 @@
 -spec(start_link/1 ::
         (rabbit_types:amqqueue()) -> rabbit_types:ok_pid_or_error()).
 -spec(info_keys/0 :: () -> rabbit_types:info_keys()).
--spec(init_with_backing_queue_state/7 ::
+-spec(init_with_backing_queue_state/8 ::
         (rabbit_types:amqqueue(), atom(), tuple(), any(), [any()],
-         [rabbit_types:delivery()], dict()) -> #q{}).
+         [rabbit_types:delivery()], pmon:pmon(), dict()) -> #q{}).
 
 -endif.
 
@@ -115,7 +119,6 @@ info_keys() -> ?INFO_KEYS.
 %%----------------------------------------------------------------------------
 
 init(Q) ->
-    ?LOGDEBUG("Queue starting - ~p~n", [Q]),
     process_flag(trap_exit, true),
 
     State = #q{q                   = Q#amqqueue{pid = self()},
@@ -129,13 +132,19 @@ init(Q) ->
                rate_timer_ref      = undefined,
                expiry_timer_ref    = undefined,
                ttl                 = undefined,
+               senders             = pmon:new(),
+               dlx                 = undefined,
+               dlx_routing_key     = undefined,
+               publish_seqno       = 1,
+               unconfirmed         = dtree:empty(),
+               delayed_stop        = undefined,
+               queue_monitors      = pmon:new(),
                msg_id_to_channel   = gb_trees:empty()},
     {ok, rabbit_event:init_stats_timer(State, #q.stats_timer), hibernate,
      {backoff, ?HIBERNATE_AFTER_MIN, ?HIBERNATE_AFTER_MIN, ?DESIRED_HIBERNATE}}.
 
 init_with_backing_queue_state(Q = #amqqueue{exclusive_owner = Owner}, BQ, BQS,
-                              RateTRef, AckTags, Deliveries, MTC) ->
-    ?LOGDEBUG("Queue starting - ~p~n", [Q]),
+                              RateTRef, AckTags, Deliveries, Senders, MTC) ->
     case Owner of
         none -> ok;
         _    -> erlang:monitor(process, Owner)
@@ -151,6 +160,11 @@ init_with_backing_queue_state(Q = #amqqueue{exclusive_owner = Owner}, BQ, BQS,
                rate_timer_ref      = RateTRef,
                expiry_timer_ref    = undefined,
                ttl                 = undefined,
+               senders             = Senders,
+               publish_seqno       = 1,
+               unconfirmed         = dtree:empty(),
+               delayed_stop        = undefined,
+               queue_monitors      = pmon:new(),
                msg_id_to_channel   = MTC},
     State1 = requeue_and_run(AckTags, process_args(
                                         rabbit_event:init_stats_timer(
@@ -166,16 +180,13 @@ terminate({shutdown, _} = R, State = #q{backing_queue = BQ}) ->
 terminate(Reason,            State = #q{q             = #amqqueue{name = QName},
                                         backing_queue = BQ}) ->
     %% FIXME: How do we cancel active subscriptions?
-    terminate_shutdown(fun (BQS) ->
-                               rabbit_event:notify(
-                                 queue_deleted, [{pid,  self()},
-                                                 {name, QName}]),
-                               BQS1 = BQ:delete_and_terminate(Reason, BQS),
-                               %% don't care if the internal delete
-                               %% doesn't return 'ok'.
-                               rabbit_amqqueue:internal_delete(qname(State)),
-                               BQS1
-                       end, State).
+    terminate_shutdown(
+      fun (BQS) ->
+              BQS1 = BQ:delete_and_terminate(Reason, BQS),
+              %% don't care if the internal delete doesn't return 'ok'.
+              rabbit_amqqueue:internal_delete(QName, self()),
+              BQS1
+      end, State).
 
 code_change(_OldVsn, State, _Extra) ->
     {ok, State}.
@@ -212,18 +223,28 @@ bq_init(BQ, Q, Recover) ->
             end).
 
 process_args(State = #q{q = #amqqueue{arguments = Arguments}}) ->
-    lists:foldl(fun({Arg, Fun}, State1) ->
-                        case rabbit_misc:table_lookup(Arguments, Arg) of
-                            {_Type, Val} -> Fun(Val, State1);
-                            undefined    -> State1
-                        end
-                end, State, [{<<"x-expires">>,     fun init_expires/2},
-                             {<<"x-message-ttl">>, fun init_ttl/2}]).
+    lists:foldl(
+      fun({Arg, Fun}, State1) ->
+              case rabbit_misc:table_lookup(Arguments, Arg) of
+                  {_Type, Val} -> Fun(Val, State1);
+                  undefined    -> State1
+              end
+      end, State,
+      [{<<"x-expires">>,                 fun init_expires/2},
+       {<<"x-message-ttl">>,             fun init_ttl/2},
+       {<<"x-dead-letter-exchange">>,    fun init_dlx/2},
+       {<<"x-dead-letter-routing-key">>, fun init_dlx_routing_key/2}]).
 
 init_expires(Expires, State) -> ensure_expiry_timer(State#q{expires = Expires}).
 
 init_ttl(TTL, State) -> drop_expired_messages(State#q{ttl = TTL}).
 
+init_dlx(DLX, State = #q{q = #amqqueue{name = QName}}) ->
+    State#q{dlx = rabbit_misc:r(QName, exchange, DLX)}.
+
+init_dlx_routing_key(RoutingKey, State) ->
+    State#q{dlx_routing_key = RoutingKey}.
+
 terminate_shutdown(Fun, State) ->
     State1 = #q{backing_queue_state = BQS} =
         stop_sync_timer(stop_rate_timer(State)),
@@ -252,9 +273,9 @@ next_state(State = #q{backing_queue = BQ, backing_queue_state = BQS}) ->
                  confirm_messages(MsgIds, State#q{
                                             backing_queue_state = BQS1}))),
     case BQ:needs_timeout(BQS1) of
-        false -> {stop_sync_timer(State1),   hibernate};
-        idle  -> {stop_sync_timer(State1),   0        };
-        timed -> {ensure_sync_timer(State1), 0        }
+        false -> {stop_sync_timer(State1),   hibernate     };
+        idle  -> {stop_sync_timer(State1),   ?SYNC_INTERVAL};
+        timed -> {ensure_sync_timer(State1), 0             }
     end.
 
 backing_queue_module(#amqqueue{arguments = Args}) ->
@@ -306,12 +327,10 @@ ensure_expiry_timer(State = #q{expires = undefined}) ->
     State;
 ensure_expiry_timer(State = #q{expires = Expires}) ->
     case is_unused(State) of
-        true ->
-            NewState = stop_expiry_timer(State),
-            TRef = erlang:send_after(Expires, self(), maybe_expire),
-            NewState#q{expiry_timer_ref = TRef};
-        false ->
-            State
+        true  -> NewState = stop_expiry_timer(State),
+                 TRef = erlang:send_after(Expires, self(), maybe_expire),
+                 NewState#q{expiry_timer_ref = TRef};
+        false -> State
     end.
 
 ensure_stats_timer(State) ->
@@ -390,34 +409,32 @@ ch_record_state_transition(OldCR, NewCR) ->
         {_, _}        -> ok
     end.
 
-deliver_msgs_to_consumers(Funs = {PredFun, DeliverFun}, FunAcc,
+deliver_msgs_to_consumers(_DeliverFun, true, State) ->
+    {true, State};
+deliver_msgs_to_consumers(DeliverFun, false,
                           State = #q{active_consumers = ActiveConsumers}) ->
-    case PredFun(FunAcc, State) of
-        false -> {FunAcc, State};
-        true  -> case queue:out(ActiveConsumers) of
-                     {empty, _} ->
-                         {FunAcc, State};
-                     {{value, QEntry}, Tail} ->
-                         {FunAcc1, State1} =
-                             deliver_msg_to_consumer(
+    case queue:out(ActiveConsumers) of
+        {empty, _} ->
+            {false, State};
+        {{value, QEntry}, Tail} ->
+            {Stop, State1} = deliver_msg_to_consumer(
                                DeliverFun, QEntry,
-                               FunAcc, State#q{active_consumers = Tail}),
-                         deliver_msgs_to_consumers(Funs, FunAcc1, State1)
-                 end
+                               State#q{active_consumers = Tail}),
+            deliver_msgs_to_consumers(DeliverFun, Stop, State1)
     end.
 
-deliver_msg_to_consumer(DeliverFun, E = {ChPid, Consumer}, FunAcc, State) ->
+deliver_msg_to_consumer(DeliverFun, E = {ChPid, Consumer}, State) ->
     C = ch_record(ChPid),
     case is_ch_blocked(C) of
         true  -> block_consumer(C, E),
-                 {FunAcc, State};
+                 {false, State};
         false -> case rabbit_limiter:can_send(C#cr.limiter, self(),
                                               Consumer#consumer.ack_required) of
                      false -> block_consumer(C#cr{is_limit_active = true}, E),
-                              {FunAcc, State};
+                              {false, State};
                      true  -> AC1 = queue:in(E, State#q.active_consumers),
                               deliver_msg_to_consumer(
-                                DeliverFun, Consumer, C, FunAcc,
+                                DeliverFun, Consumer, C,
                                 State#q{active_consumers = AC1})
                  end
     end.
@@ -428,9 +445,9 @@ deliver_msg_to_consumer(DeliverFun,
                         C = #cr{ch_pid               = ChPid,
                                 acktags              = ChAckTags,
                                 unsent_message_count = Count},
-                        FunAcc, State = #q{q = #amqqueue{name = QName}}) ->
-    {{Message, IsDelivered, AckTag}, FunAcc1, State1} =
-        DeliverFun(AckRequired, FunAcc, State),
+                        State = #q{q = #amqqueue{name = QName}}) ->
+    {{Message, IsDelivered, AckTag}, Stop, State1} =
+        DeliverFun(AckRequired, State),
     rabbit_channel:deliver(ChPid, ConsumerTag, AckRequired,
                            {QName, self(), AckTag, IsDelivered, Message}),
     ChAckTags1 = case AckRequired of
@@ -439,11 +456,9 @@ deliver_msg_to_consumer(DeliverFun,
                  end,
     update_ch_record(C#cr{acktags              = ChAckTags1,
                           unsent_message_count = Count + 1}),
-    {FunAcc1, State1}.
+    {Stop, State1}.
 
-deliver_from_queue_pred(IsEmpty, _State) -> not IsEmpty.
-
-deliver_from_queue_deliver(AckRequired, false, State) ->
+deliver_from_queue_deliver(AckRequired, State) ->
     {{Message, IsDelivered, AckTag, Remaining}, State1} =
         fetch(AckRequired, State),
     {{Message, IsDelivered, AckTag}, 0 == Remaining, State1}.
@@ -455,100 +470,96 @@ confirm_messages(MsgIds, State = #q{msg_id_to_channel = MTC}) ->
         lists:foldl(
           fun(MsgId, {CMs, MTC0}) ->
                   case gb_trees:lookup(MsgId, MTC0) of
-                      {value, {ChPid, MsgSeqNo}} ->
-                          {rabbit_misc:gb_trees_cons(ChPid, MsgSeqNo, CMs),
+                      {value, {SenderPid, MsgSeqNo}} ->
+                          {rabbit_misc:gb_trees_cons(SenderPid,
+                                                     MsgSeqNo, CMs),
                            gb_trees:delete(MsgId, MTC0)};
                       none ->
                           {CMs, MTC0}
                   end
           end, {gb_trees:empty(), MTC}, MsgIds),
-    rabbit_misc:gb_trees_foreach(fun rabbit_channel:confirm/2, CMs),
+    rabbit_misc:gb_trees_foreach(fun rabbit_misc:confirm_to_sender/2, CMs),
     State#q{msg_id_to_channel = MTC1}.
 
 should_confirm_message(#delivery{msg_seq_no = undefined}, _State) ->
     never;
-should_confirm_message(#delivery{sender     = ChPid,
+should_confirm_message(#delivery{sender     = SenderPid,
                                  msg_seq_no = MsgSeqNo,
                                  message    = #basic_message {
                                    is_persistent = true,
                                    id            = MsgId}},
                        #q{q = #amqqueue{durable = true}}) ->
-    {eventually, ChPid, MsgSeqNo, MsgId};
-should_confirm_message(_Delivery, _State) ->
-    immediately.
+    {eventually, SenderPid, MsgSeqNo, MsgId};
+should_confirm_message(#delivery{sender     = SenderPid,
+                                 msg_seq_no = MsgSeqNo},
+                       _State) ->
+    {immediately, SenderPid, MsgSeqNo}.
 
 needs_confirming({eventually, _, _, _}) -> true;
 needs_confirming(_)                     -> false.
 
-maybe_record_confirm_message({eventually, ChPid, MsgSeqNo, MsgId},
+maybe_record_confirm_message({eventually, SenderPid, MsgSeqNo, MsgId},
                              State = #q{msg_id_to_channel = MTC}) ->
-    State#q{msg_id_to_channel = gb_trees:insert(MsgId, {ChPid, MsgSeqNo}, MTC)};
+    State#q{msg_id_to_channel =
+                gb_trees:insert(MsgId, {SenderPid, MsgSeqNo}, MTC)};
+maybe_record_confirm_message({immediately, SenderPid, MsgSeqNo}, State) ->
+    rabbit_misc:confirm_to_sender(SenderPid, [MsgSeqNo]),
+    State;
 maybe_record_confirm_message(_Confirm, State) ->
     State.
 
 run_message_queue(State) ->
-    Funs = {fun deliver_from_queue_pred/2,
-            fun deliver_from_queue_deliver/3},
     State1 = #q{backing_queue = BQ, backing_queue_state = BQS} =
         drop_expired_messages(State),
-    IsEmpty = BQ:is_empty(BQS),
-    {_IsEmpty1, State2} = deliver_msgs_to_consumers(Funs, IsEmpty, State1),
+    {_IsEmpty1, State2} = deliver_msgs_to_consumers(
+                            fun deliver_from_queue_deliver/2,
+                            BQ:is_empty(BQS), State1),
     State2.
 
-attempt_delivery(Delivery = #delivery{sender     = ChPid,
-                                      message    = Message,
-                                      msg_seq_no = MsgSeqNo},
+attempt_delivery(#delivery{sender = SenderPid, message = Message}, Confirm,
                  State = #q{backing_queue = BQ, backing_queue_state = BQS}) ->
-    Confirm = should_confirm_message(Delivery, State),
-    case Confirm of
-        immediately -> rabbit_channel:confirm(ChPid, [MsgSeqNo]);
-        _           -> ok
-    end,
     case BQ:is_duplicate(Message, BQS) of
         {false, BQS1} ->
-            PredFun = fun (IsEmpty, _State) -> not IsEmpty end,
-            DeliverFun =
-                fun (AckRequired, false,
-                     State1 = #q{backing_queue_state = BQS2}) ->
-                        %% we don't need an expiry here because
-                        %% messages are not being enqueued, so we use
-                        %% an empty message_properties.
-                        {AckTag, BQS3} =
-                            BQ:publish_delivered(
-                              AckRequired, Message,
-                              (?BASE_MESSAGE_PROPERTIES)#message_properties{
-                                needs_confirming = needs_confirming(Confirm)},
-                              ChPid, BQS2),
-                        {{Message, false, AckTag}, true,
-                         State1#q{backing_queue_state = BQS3}}
-                end,
-            {Delivered, State2} =
-                deliver_msgs_to_consumers({ PredFun, DeliverFun }, false,
-                                          State#q{backing_queue_state = BQS1}),
-            {Delivered, Confirm, State2};
+            deliver_msgs_to_consumers(
+              fun (AckRequired, State1 = #q{backing_queue_state = BQS2}) ->
+                      Props = message_properties(Confirm, State1),
+                      {AckTag, BQS3} = BQ:publish_delivered(
+                                         AckRequired, Message, Props,
+                                         SenderPid, BQS2),
+                      {{Message, false, AckTag}, true,
+                       State1#q{backing_queue_state = BQS3}}
+              end, false, State#q{backing_queue_state = BQS1});
         {Duplicate, BQS1} ->
             %% if the message has previously been seen by the BQ then
             %% it must have been seen under the same circumstances as
             %% now: i.e. if it is now a deliver_immediately then it
             %% must have been before.
-            Delivered = case Duplicate of
-                            published -> true;
-                            discarded -> false
-                        end,
-            {Delivered, Confirm, State#q{backing_queue_state = BQS1}}
+            {case Duplicate of
+                 published -> true;
+                 discarded -> false
+             end,
+             State#q{backing_queue_state = BQS1}}
     end.
 
-deliver_or_enqueue(Delivery = #delivery{message = Message,
-                                        sender  = ChPid}, State) ->
-    {Delivered, Confirm, State1} = attempt_delivery(Delivery, State),
-    State2 = #q{backing_queue = BQ, backing_queue_state = BQS} =
-        maybe_record_confirm_message(Confirm, State1),
-    case Delivered of
-        true  -> State2;
-        false -> Props = (message_properties(State)) #message_properties{
-                           needs_confirming = needs_confirming(Confirm)},
-                 BQS1 = BQ:publish(Message, Props, ChPid, BQS),
-                 ensure_ttl_timer(State2#q{backing_queue_state = BQS1})
+deliver_or_enqueue(Delivery = #delivery{message    = Message,
+                                        msg_seq_no = MsgSeqNo,
+                                        sender     = SenderPid}, State) ->
+    Confirm = should_confirm_message(Delivery, State),
+    case attempt_delivery(Delivery, Confirm, State) of
+        {true, State1} ->
+            maybe_record_confirm_message(Confirm, State1);
+        %% the next two are optimisations
+        {false, State1 = #q{ttl = 0, dlx = undefined}} when Confirm == never ->
+            discard_delivery(Delivery, State1);
+        {false, State1 = #q{ttl = 0, dlx = undefined}} ->
+            rabbit_misc:confirm_to_sender(SenderPid, [MsgSeqNo]),
+            discard_delivery(Delivery, State1);
+        {false, State1} ->
+            State2 = #q{backing_queue = BQ, backing_queue_state = BQS} =
+                maybe_record_confirm_message(Confirm, State1),
+            Props = message_properties(Confirm, State2),
+            BQS1 = BQ:publish(Message, Props, SenderPid, BQS),
+            ensure_ttl_timer(State2#q{backing_queue_state = BQS1})
     end.
 
 requeue_and_run(AckTags, State = #q{backing_queue = BQ}) ->
@@ -597,10 +608,16 @@ should_auto_delete(#q{q = #amqqueue{auto_delete = false}}) -> false;
 should_auto_delete(#q{has_had_consumers = false}) -> false;
 should_auto_delete(State) -> is_unused(State).
 
-handle_ch_down(DownPid, State = #q{exclusive_consumer = Holder}) ->
+handle_ch_down(DownPid, State = #q{exclusive_consumer = Holder,
+                                   senders            = Senders}) ->
+    Senders1 = case pmon:is_monitored(DownPid, Senders) of
+                   false -> Senders;
+                   true  -> credit_flow:peer_down(DownPid),
+                            pmon:demonitor(DownPid, Senders)
+               end,
     case lookup_ch(DownPid) of
         not_found ->
-            {ok, State};
+            {ok, State#q{senders = Senders1}};
         C = #cr{ch_pid            = ChPid,
                 acktags           = ChAckTags,
                 blocked_consumers = Blocked} ->
@@ -612,7 +629,8 @@ handle_ch_down(DownPid, State = #q{exclusive_consumer = Holder}) ->
                                                 Other      -> Other
                                             end,
                        active_consumers = remove_consumers(
-                                            ChPid, State#q.active_consumers)},
+                                            ChPid, State#q.active_consumers),
+                       senders          = Senders1},
             case should_auto_delete(State1) of
                 true  -> {stop, State1};
                 false -> {ok, requeue_and_run(sets:to_list(ChAckTags),
@@ -662,14 +680,15 @@ subtract_acks(ChPid, AckTags, State, Fun) ->
             Fun(State)
     end.
 
-discard_delivery(#delivery{sender = ChPid,
+discard_delivery(#delivery{sender = SenderPid,
                            message = Message},
                  State = #q{backing_queue = BQ,
                             backing_queue_state = BQS}) ->
-    State#q{backing_queue_state = BQ:discard(Message, ChPid, BQS)}.
+    State#q{backing_queue_state = BQ:discard(Message, SenderPid, BQS)}.
 
-message_properties(#q{ttl=TTL}) ->
-    #message_properties{expiry = calculate_msg_expiry(TTL)}.
+message_properties(Confirm, #q{ttl = TTL}) ->
+    #message_properties{expiry           = calculate_msg_expiry(TTL),
+                        needs_confirming = needs_confirming(Confirm)}.
 
 calculate_msg_expiry(undefined) -> undefined;
 calculate_msg_expiry(TTL)       -> now_micros() + (TTL * 1000).
@@ -677,11 +696,18 @@ calculate_msg_expiry(TTL)       -> now_micros() + (TTL * 1000).
 drop_expired_messages(State = #q{ttl = undefined}) ->
     State;
 drop_expired_messages(State = #q{backing_queue_state = BQS,
-                                 backing_queue = BQ}) ->
+                                 backing_queue       = BQ }) ->
     Now = now_micros(),
-    BQS1 = BQ:dropwhile(
-             fun (#message_properties{expiry = Expiry}) -> Now > Expiry end,
-             BQS),
+    DLXFun = dead_letter_fun(expired, State),
+    ExpirePred = fun (#message_properties{expiry = Expiry}) -> Now > Expiry end,
+    case DLXFun of
+        undefined -> {undefined, BQS1} = BQ:dropwhile(ExpirePred, false, BQS),
+                     BQS1;
+        _         -> {Msgs, BQS1} = BQ:dropwhile(ExpirePred, true, BQS),
+                     lists:foreach(
+                       fun({Msg, AckTag}) -> DLXFun(Msg, AckTag) end, Msgs),
+                     BQS1
+    end,
     ensure_ttl_timer(State#q{backing_queue_state = BQS1}).
 
 ensure_ttl_timer(State = #q{backing_queue       = BQ,
@@ -697,6 +723,156 @@ ensure_ttl_timer(State = #q{backing_queue       = BQ,
 ensure_ttl_timer(State) ->
     State.
 
+ack_if_no_dlx(AckTags, State = #q{dlx                 = undefined,
+                                  backing_queue       = BQ,
+                                  backing_queue_state = BQS }) ->
+    {_Guids, BQS1} = BQ:ack(AckTags, BQS),
+    State#q{backing_queue_state = BQS1};
+ack_if_no_dlx(_AckTags, State) ->
+    State.
+
+dead_letter_fun(_Reason, #q{dlx = undefined}) ->
+    undefined;
+dead_letter_fun(Reason, _State) ->
+    fun(Msg, AckTag) ->
+            gen_server2:cast(self(), {dead_letter, {Msg, AckTag}, Reason})
+    end.
+
+dead_letter_publish(Msg, Reason, State = #q{publish_seqno = MsgSeqNo}) ->
+    DLMsg = #basic_message{exchange_name = XName} =
+        make_dead_letter_msg(Reason, Msg, State),
+    case rabbit_exchange:lookup(XName) of
+        {ok, X} ->
+            Delivery = rabbit_basic:delivery(false, false, DLMsg, MsgSeqNo),
+            {Queues, Cycles} = detect_dead_letter_cycles(
+                                 DLMsg, rabbit_exchange:route(X, Delivery)),
+            lists:foreach(fun log_cycle_once/1, Cycles),
+            QPids = rabbit_amqqueue:lookup(Queues),
+            {_, DeliveredQPids} = rabbit_amqqueue:deliver(QPids, Delivery),
+            DeliveredQPids;
+        {error, not_found} ->
+            []
+    end.
+
+dead_letter_msg(Msg, AckTag, Reason, State = #q{publish_seqno = MsgSeqNo,
+                                                unconfirmed   = UC}) ->
+    QPids = dead_letter_publish(Msg, Reason, State),
+    State1 = State#q{queue_monitors = pmon:monitor_all(
+                                        QPids, State#q.queue_monitors),
+                     publish_seqno  = MsgSeqNo + 1},
+    case QPids of
+        [] -> cleanup_after_confirm([AckTag], State1);
+        _  -> UC1 = dtree:insert(MsgSeqNo, QPids, AckTag, UC),
+              noreply(State1#q{unconfirmed = UC1})
+    end.
+
+handle_queue_down(QPid, Reason, State = #q{queue_monitors = QMons,
+                                           unconfirmed    = UC}) ->
+    case pmon:is_monitored(QPid, QMons) of
+        false -> noreply(State);
+        true  -> case rabbit_misc:is_abnormal_termination(Reason) of
+                     true  -> {Lost, _UC1} = dtree:take_all(QPid, UC),
+                              QNameS = rabbit_misc:rs(qname(State)),
+                              rabbit_log:warning("DLQ ~p for ~s died with "
+                                                 "~p unconfirmed messages~n",
+                                                 [QPid, QNameS, length(Lost)]);
+                     false -> ok
+                 end,
+                 {MsgSeqNoAckTags, UC1} = dtree:take(QPid, UC),
+                 cleanup_after_confirm(
+                   [AckTag || {_MsgSeqNo, AckTag} <- MsgSeqNoAckTags],
+                   State#q{queue_monitors = pmon:erase(QPid, QMons),
+                           unconfirmed    = UC1})
+    end.
+
+stop_later(Reason, State) ->
+    stop_later(Reason, undefined, noreply, State).
+
+stop_later(Reason, From, Reply, State = #q{unconfirmed = UC}) ->
+    case {dtree:is_empty(UC), Reply} of
+        {true, noreply} ->
+            {stop, Reason, State};
+        {true, _} ->
+            {stop, Reason, Reply, State};
+        {false, _} ->
+            noreply(State#q{delayed_stop = {Reason, {From, Reply}}})
+    end.
+
+cleanup_after_confirm(AckTags, State = #q{delayed_stop        = DS,
+                                          unconfirmed         = UC,
+                                          backing_queue       = BQ,
+                                          backing_queue_state = BQS}) ->
+    {_Guids, BQS1} = BQ:ack(AckTags, BQS),
+    State1 = State#q{backing_queue_state = BQS1},
+    case dtree:is_empty(UC) andalso DS =/= undefined of
+        true  -> case DS of
+                     {_, {_, noreply}}  -> ok;
+                     {_, {From, Reply}} -> gen_server2:reply(From, Reply)
+                 end,
+                 {Reason, _} = DS,
+                 {stop, Reason, State1};
+        false -> noreply(State1)
+    end.
+
+detect_dead_letter_cycles(#basic_message{content = Content}, Queues) ->
+    #content{properties = #'P_basic'{headers = Headers}} =
+        rabbit_binary_parser:ensure_content_decoded(Content),
+    NoCycles = {Queues, []},
+    case Headers of
+        undefined ->
+            NoCycles;
+        _ ->
+            case rabbit_misc:table_lookup(Headers, <<"x-death">>) of
+                {array, DeathTables} ->
+                    OldQueues = [rabbit_misc:table_lookup(D, <<"queue">>) ||
+                                    {table, D} <- DeathTables],
+                    OldQueues1 = [QName || {longstr, QName} <- OldQueues],
+                    OldQueuesSet = ordsets:from_list(OldQueues1),
+                    {Cycling, NotCycling} =
+                        lists:partition(
+                          fun(Queue) ->
+                                  ordsets:is_element(Queue#resource.name,
+                                                     OldQueuesSet)
+                          end, Queues),
+                    {NotCycling, [[QName | OldQueues1] ||
+                                     #resource{name = QName} <- Cycling]};
+                _ ->
+                    NoCycles
+            end
+    end.
+
+make_dead_letter_msg(Reason,
+                     Msg = #basic_message{content       = Content,
+                                          exchange_name = Exchange,
+                                          routing_keys  = RoutingKeys},
+                     State = #q{dlx = DLX, dlx_routing_key = DlxRoutingKey}) ->
+    {DeathRoutingKeys, HeadersFun1} =
+        case DlxRoutingKey of
+            undefined -> {RoutingKeys, fun (H) -> H end};
+            _         -> {[DlxRoutingKey],
+                          fun (H) -> lists:keydelete(<<"CC">>, 1, H) end}
+        end,
+    ReasonBin = list_to_binary(atom_to_list(Reason)),
+    #resource{name = QName} = qname(State),
+    TimeSec = rabbit_misc:now_ms() div 1000,
+    HeadersFun2 =
+        fun (Headers) ->
+                %% The first routing key is the one specified in the
+                %% basic.publish; all others are CC or BCC keys.
+                RKs  = [hd(RoutingKeys) | rabbit_basic:header_routes(Headers)],
+                RKs1 = [{longstr, Key} || Key <- RKs],
+                Info = [{<<"reason">>,       longstr,   ReasonBin},
+                        {<<"queue">>,        longstr,   QName},
+                        {<<"time">>,         timestamp, TimeSec},
+                        {<<"exchange">>,     longstr,   Exchange#resource.name},
+                        {<<"routing-keys">>, array,     RKs1}],
+                HeadersFun1(rabbit_basic:append_table_header(<<"x-death">>,
+                                                             Info, Headers))
+        end,
+    Content1 = rabbit_basic:map_headers(HeadersFun2, Content),
+    Msg#basic_message{exchange_name = DLX, id = rabbit_guid:gen(),
+                      routing_keys = DeathRoutingKeys, content = Content1}.
+
 now_micros() -> timer:now_diff(now(), {0,0,0}).
 
 infos(Items, State) ->
@@ -713,15 +889,12 @@ infos(Items, State) ->
                || Item <- (Items1 -- [synchronised_slave_pids])].
 
 slaves_status(#q{q = #amqqueue{name = Name}}) ->
-    {ok, #amqqueue{mirror_nodes = MNodes, slave_pids = SPids}} =
-        rabbit_amqqueue:lookup(Name),
-    case MNodes of
-        undefined ->
+    case rabbit_amqqueue:lookup(Name) of
+        {ok, #amqqueue{mirror_nodes = undefined}} ->
             [{slave_pids, ''}, {synchronised_slave_pids, ''}];
-        _ ->
+        {ok, #amqqueue{slave_pids = SPids}} ->
             {Results, _Bad} =
-                delegate:invoke(
-                  SPids, fun (Pid) -> rabbit_mirror_queue_slave:info(Pid) end),
+                delegate:invoke(SPids, fun rabbit_mirror_queue_slave:info/1),
             {SPids1, SSPids} =
                 lists:foldl(
                   fun ({Pid, Infos}, {SPidsN, SSPidsN}) ->
@@ -765,11 +938,9 @@ i(memory, _) ->
     {memory, M} = process_info(self(), memory),
     M;
 i(slave_pids, #q{q = #amqqueue{name = Name}}) ->
-    {ok, #amqqueue{mirror_nodes = MNodes,
-                   slave_pids = SPids}} = rabbit_amqqueue:lookup(Name),
-    case MNodes of
-        undefined -> [];
-        _         -> SPids
+    case rabbit_amqqueue:lookup(Name) of
+        {ok, #amqqueue{mirror_nodes = undefined}} -> [];
+        {ok, #amqqueue{slave_pids = SPids}}       -> SPids
     end;
 i(backing_queue_status, #q{backing_queue_state = BQS, backing_queue = BQ}) ->
     BQ:status(BQS);
@@ -826,7 +997,7 @@ prioritise_cast(Msg, _State) ->
         {set_maximum_since_use, _Age}        -> 8;
         {ack, _AckTags, _ChPid}              -> 7;
         {reject, _AckTags, _Requeue, _ChPid} -> 7;
-        {notify_sent, _ChPid}                -> 7;
+        {notify_sent, _ChPid, _Credit}       -> 7;
         {unblock, _ChPid}                    -> 7;
         {run_backing_queue, _Mod, _Fun}      -> 6;
         _                                    -> 0
@@ -843,6 +1014,9 @@ prioritise_info(Msg, #q{q = #amqqueue{exclusive_owner = DownPid}}) ->
         _                                    -> 0
     end.
 
+handle_call(_, _, State = #q{delayed_stop = DS}) when DS =/= undefined ->
+    noreply(State);
+
 handle_call({init, Recover}, From,
             State = #q{q = #amqqueue{exclusive_owner = none}}) ->
     declare(Recover, From, State);
@@ -877,9 +1051,7 @@ handle_call({info, Items}, _From, State) ->
 handle_call(consumers, _From, State) ->
     reply(consumers(State), State);
 
-handle_call({deliver_immediately, Delivery}, _From, State) ->
-    %% Synchronous, "immediate" delivery mode
-    %%
+handle_call({deliver, Delivery = #delivery{immediate = true}}, _From, State) ->
     %% FIXME: Is this correct semantics?
     %%
     %% I'm worried in particular about the case where an exchange has
@@ -891,26 +1063,26 @@ handle_call({deliver_immediately, Delivery}, _From, State) ->
     %% just all ready-to-consume queues get the message, with unready
     %% queues discarding the message?
     %%
-    {Delivered, Confirm, State1} = attempt_delivery(Delivery, State),
+    Confirm = should_confirm_message(Delivery, State),
+    {Delivered, State1} = attempt_delivery(Delivery, Confirm, State),
     reply(Delivered, case Delivered of
                          true  -> maybe_record_confirm_message(Confirm, State1);
                          false -> discard_delivery(Delivery, State1)
                      end);
 
-handle_call({deliver, Delivery}, From, State) ->
-    %% Synchronous, "mandatory" delivery mode. Reply asap.
+handle_call({deliver, Delivery = #delivery{mandatory = true}}, From, State) ->
     gen_server2:reply(From, true),
     noreply(deliver_or_enqueue(Delivery, State));
 
-handle_call({notify_down, ChPid}, _From, State) ->
+handle_call({notify_down, ChPid}, From, State) ->
     %% we want to do this synchronously, so that auto_deleted queues
     %% are no longer visible by the time we send a response to the
     %% client.  The queue is ultimately deleted in terminate/2; if we
     %% return stop with a reply, terminate/2 will be called by
     %% gen_server2 *before* the reply is sent.
     case handle_ch_down(ChPid, State) of
-        {ok, NewState}   -> reply(ok, NewState);
-        {stop, NewState} -> {stop, normal, ok, NewState}
+        {ok, State1}   -> reply(ok, State1);
+        {stop, State1} -> stop_later(normal, From, ok, State1)
     end;
 
 handle_call({basic_get, ChPid, NoAck}, _From,
@@ -965,7 +1137,7 @@ handle_call({basic_consume, NoAck, ChPid, Limiter,
             reply(ok, State2)
     end;
 
-handle_call({basic_cancel, ChPid, ConsumerTag, OkMsg}, _From,
+handle_call({basic_cancel, ChPid, ConsumerTag, OkMsg}, From,
             State = #q{exclusive_consumer = Holder}) ->
     ok = maybe_send_reply(ChPid, OkMsg),
     case lookup_ch(ChPid) of
@@ -985,7 +1157,7 @@ handle_call({basic_cancel, ChPid, ConsumerTag, OkMsg}, _From,
                                              State#q.active_consumers)},
             case should_auto_delete(State1) of
                 false -> reply(ok, ensure_expiry_timer(State1));
-                true  -> {stop, normal, ok, State1}
+                true  -> stop_later(normal, From, ok, State1)
             end
     end;
 
@@ -994,20 +1166,18 @@ handle_call(stat, _From, State) ->
         drop_expired_messages(ensure_expiry_timer(State)),
     reply({ok, BQ:len(BQS), active_consumer_count()}, State1);
 
-handle_call({delete, IfUnused, IfEmpty}, _From,
+handle_call({delete, IfUnused, IfEmpty}, From,
             State = #q{backing_queue_state = BQS, backing_queue = BQ}) ->
     IsEmpty = BQ:is_empty(BQS),
     IsUnused = is_unused(State),
     if
-        IfEmpty and not(IsEmpty) ->
-            reply({error, not_empty}, State);
-        IfUnused and not(IsUnused) ->
-            reply({error, in_use}, State);
-        true ->
-            {stop, normal, {ok, BQ:len(BQS)}, State}
+        IfEmpty and not(IsEmpty)   -> reply({error, not_empty}, State);
+        IfUnused and not(IsUnused) -> reply({error, in_use}, State);
+        true                       -> stop_later(normal, From,
+                                                 {ok, BQ:len(BQS)}, State)
     end;
 
-handle_call(purge, _From, State = #q{backing_queue = BQ,
+handle_call(purge, _From, State = #q{backing_queue       = BQ,
                                      backing_queue_state = BQS}) ->
     {Count, BQS1} = BQ:purge(BQS),
     reply({ok, Count}, State#q{backing_queue_state = BQS1});
@@ -1016,14 +1186,45 @@ handle_call({requeue, AckTags, ChPid}, From, State) ->
     gen_server2:reply(From, ok),
     noreply(subtract_acks(
               ChPid, AckTags, State,
-              fun (State1) -> requeue_and_run(AckTags, State1) end)).
+              fun (State1) -> requeue_and_run(AckTags, State1) end));
+
+handle_call(force_event_refresh, _From,
+            State = #q{exclusive_consumer = Exclusive}) ->
+    rabbit_event:notify(queue_created, infos(?CREATION_EVENT_KEYS, State)),
+    case Exclusive of
+        none       -> [emit_consumer_created(Ch, CTag, false, AckRequired) ||
+                          {Ch, CTag, AckRequired} <- consumers(State)];
+        {Ch, CTag} -> [{Ch, CTag, AckRequired}] = consumers(State),
+                      emit_consumer_created(Ch, CTag, true, AckRequired)
+    end,
+    reply(ok, State).
+
+handle_cast({confirm, MsgSeqNos, QPid}, State = #q{unconfirmed = UC}) ->
+    {MsgSeqNoAckTags, UC1} = dtree:take(MsgSeqNos, QPid, UC),
+    State1 = case dtree:is_defined(QPid, UC1) of
+                 false -> QMons = State#q.queue_monitors,
+                          State#q{queue_monitors = pmon:demonitor(QPid, QMons)};
+                 true  -> State
+             end,
+    cleanup_after_confirm([AckTag || {_MsgSeqNo, AckTag} <- MsgSeqNoAckTags],
+                          State1#q{unconfirmed = UC1});
+
+handle_cast(_, State = #q{delayed_stop = DS}) when DS =/= undefined ->
+    noreply(State);
 
 handle_cast({run_backing_queue, Mod, Fun}, State) ->
     noreply(run_backing_queue(Mod, Fun, State));
 
-handle_cast({deliver, Delivery}, State) ->
+handle_cast({deliver, Delivery = #delivery{sender = Sender}, Flow},
+            State = #q{senders = Senders}) ->
     %% Asynchronous, non-"mandatory", non-"immediate" deliver mode.
-    noreply(deliver_or_enqueue(Delivery, State));
+    Senders1 = case Flow of
+                   flow   -> credit_flow:ack(Sender),
+                             pmon:monitor(Sender, Senders);
+                   noflow -> Senders
+               end,
+    State1 = State#q{senders = Senders1},
+    noreply(deliver_or_enqueue(Delivery, State1));
 
 handle_cast({ack, AckTags, ChPid}, State) ->
     noreply(subtract_acks(
@@ -1037,28 +1238,31 @@ handle_cast({ack, AckTags, ChPid}, State) ->
 handle_cast({reject, AckTags, Requeue, ChPid}, State) ->
     noreply(subtract_acks(
               ChPid, AckTags, State,
-              fun (State1 = #q{backing_queue       = BQ,
-                               backing_queue_state = BQS}) ->
-                      case Requeue of
-                          true  -> requeue_and_run(AckTags, State1);
-                          false -> {_Guids, BQS1} = BQ:ack(AckTags, BQS),
-                                   State1#q{backing_queue_state = BQS1}
-                      end
+              case Requeue of
+                  true  -> fun (State1) -> requeue_and_run(AckTags, State1) end;
+                  false -> fun (State1 = #q{backing_queue       = BQ,
+                                            backing_queue_state = BQS}) ->
+                                   Fun = dead_letter_fun(rejected, State1),
+                                   BQS1 = BQ:fold(Fun, BQS, AckTags),
+                                   ack_if_no_dlx(
+                                     AckTags,
+                                     State1#q{backing_queue_state = BQS1})
+                           end
               end));
 
 handle_cast(delete_immediately, State) ->
-    {stop, normal, State};
+    stop_later(normal, State);
 
 handle_cast({unblock, ChPid}, State) ->
     noreply(
       possibly_unblock(State, ChPid,
                        fun (C) -> C#cr{is_limit_active = false} end));
 
-handle_cast({notify_sent, ChPid}, State) ->
+handle_cast({notify_sent, ChPid, Credit}, State) ->
     noreply(
       possibly_unblock(State, ChPid,
                        fun (C = #cr{unsent_message_count = Count}) ->
-                               C#cr{unsent_message_count = Count - 1}
+                               C#cr{unsent_message_count = Count - Credit}
                        end));
 
 handle_cast({limit, ChPid, Limiter}, State) ->
@@ -1090,20 +1294,21 @@ handle_cast({set_maximum_since_use, Age}, State) ->
     ok = file_handle_cache:set_maximum_since_use(Age),
     noreply(State);
 
-handle_cast(force_event_refresh, State = #q{exclusive_consumer = Exclusive}) ->
-    rabbit_event:notify(queue_created, infos(?CREATION_EVENT_KEYS, State)),
-    case Exclusive of
-        none       -> [emit_consumer_created(Ch, CTag, false, AckRequired) ||
-                          {Ch, CTag, AckRequired} <- consumers(State)];
-        {Ch, CTag} -> [{Ch, CTag, AckRequired}] = consumers(State),
-                      emit_consumer_created(Ch, CTag, true, AckRequired)
-    end,
-    noreply(State).
+handle_cast({dead_letter, {Msg, AckTag}, Reason}, State) ->
+    dead_letter_msg(Msg, AckTag, Reason, State).
+
+%% We need to not ignore this as we need to remove outstanding
+%% confirms due to queue death.
+handle_info({'DOWN', _MonitorRef, process, DownPid, Reason},
+            State = #q{delayed_stop = DS}) when DS =/= undefined ->
+    handle_queue_down(DownPid, Reason, State);
+
+handle_info(_, State = #q{delayed_stop = DS}) when DS =/= undefined ->
+    noreply(State);
 
 handle_info(maybe_expire, State) ->
     case is_unused(State) of
-        true  -> ?LOGDEBUG("Queue lease expired for ~p~n", [State#q.q]),
-                 {stop, normal, State};
+        true  -> stop_later(normal, State);
         false -> noreply(ensure_expiry_timer(State))
     end;
 
@@ -1125,11 +1330,12 @@ handle_info({'DOWN', _MonitorRef, process, DownPid, _Reason},
     %% match what people expect (see bug 21824). However we need this
     %% monitor-and-async- delete in case the connection goes away
     %% unexpectedly.
-    {stop, normal, State};
-handle_info({'DOWN', _MonitorRef, process, DownPid, _Reason}, State) ->
+    stop_later(normal, State);
+
+handle_info({'DOWN', _MonitorRef, process, DownPid, Reason}, State) ->
     case handle_ch_down(DownPid, State) of
-        {ok, NewState}   -> noreply(NewState);
-        {stop, NewState} -> {stop, normal, NewState}
+        {ok, State1}   -> handle_queue_down(DownPid, Reason, State1);
+        {stop, State1} -> stop_later(normal, State1)
     end;
 
 handle_info(update_ram_duration, State = #q{backing_queue = BQ,
@@ -1150,8 +1356,11 @@ handle_info(timeout, State) ->
 handle_info({'EXIT', _Pid, Reason}, State) ->
     {stop, Reason, State};
 
+handle_info({bump_credit, Msg}, State) ->
+    credit_flow:handle_bump_msg(Msg),
+    noreply(State);
+
 handle_info(Info, State) ->
-    ?LOGDEBUG("Info in queue: ~p~n", [Info]),
     {stop, {unhandled_info, Info}, State}.
 
 handle_pre_hibernate(State = #q{backing_queue_state = undefined}) ->
@@ -1171,3 +1380,14 @@ handle_pre_hibernate(State = #q{backing_queue = BQ,
     {hibernate, stop_rate_timer(State1)}.
 
 format_message_queue(Opt, MQ) -> rabbit_misc:format_message_queue(Opt, MQ).
+
+log_cycle_once(Queues) ->
+    Key = {queue_cycle, Queues},
+    case get(Key) of
+        true      -> ok;
+        undefined -> rabbit_log:warning(
+                       "Message dropped. Dead-letter queues cycle detected" ++
+                       ": ~p~nThis cycle will NOT be reported again.~n",
+                       [Queues]),
+                     put(Key, true)
+    end.
diff --git a/src/rabbit_amqqueue_sup.erl b/src/rabbit_amqqueue_sup.erl
index 7b3ebcf2..a4305e5f 100644
--- a/src/rabbit_amqqueue_sup.erl
+++ b/src/rabbit_amqqueue_sup.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_amqqueue_sup).
diff --git a/src/rabbit_auth_backend.erl b/src/rabbit_auth_backend.erl
index ade158bb..e89951e7 100644
--- a/src/rabbit_auth_backend.erl
+++ b/src/rabbit_auth_backend.erl
@@ -11,47 +11,62 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_auth_backend).
 
+-ifdef(use_specs).
+
+%% A description proplist as with auth mechanisms,
+%% exchanges. Currently unused.
+-callback description() -> [proplist:property()].
+
+%% Check a user can log in, given a username and a proplist of
+%% authentication information (e.g. [{password, Password}]).
+%%
+%% Possible responses:
+%% {ok, User}
+%%     Authentication succeeded, and here's the user record.
+%% {error, Error}
+%%     Something went wrong. Log and die.
+%% {refused, Msg, Args}
+%%     Client failed authentication. Log and die.
+-callback check_user_login(rabbit_types:username(), [term()]) ->
+    {'ok', rabbit_types:user()} |
+    {'refused', string(), [any()]} |
+    {'error', any()}.
+
+%% Given #user and vhost, can a user log in to a vhost?
+%% Possible responses:
+%% true
+%% false
+%% {error, Error}
+%%     Something went wrong. Log and die.
+-callback check_vhost_access(rabbit_types:user(), rabbit_types:vhost()) ->
+    boolean() | {'error', any()}.
+
+
+%% Given #user, resource and permission, can a user access a resource?
+%%
+%% Possible responses:
+%% true
+%% false
+%% {error, Error}
+%%     Something went wrong. Log and die.
+-callback check_resource_access(rabbit_types:user(),
+                                rabbit_types:r(atom()),
+                                rabbit_access_control:permission_atom()) ->
+    boolean() | {'error', any()}.
+
+-else.
+
 -export([behaviour_info/1]).
 
 behaviour_info(callbacks) ->
-    [
-     %% A description proplist as with auth mechanisms,
-     %% exchanges. Currently unused.
-     {description, 0},
-
-     %% Check a user can log in, given a username and a proplist of
-     %% authentication information (e.g. [{password, Password}]).
-     %%
-     %% Possible responses:
-     %% {ok, User}
-     %%     Authentication succeeded, and here's the user record.
-     %% {error, Error}
-     %%     Something went wrong. Log and die.
-     %% {refused, Msg, Args}
-     %%     Client failed authentication. Log and die.
-     {check_user_login, 2},
-
-     %% Given #user and vhost, can a user log in to a vhost?
-     %% Possible responses:
-     %% true
-     %% false
-     %% {error, Error}
-     %%     Something went wrong. Log and die.
-     {check_vhost_access, 2},
-
-     %% Given #user, resource and permission, can a user access a resource?
-     %%
-     %% Possible responses:
-     %% true
-     %% false
-     %% {error, Error}
-     %%     Something went wrong. Log and die.
-     {check_resource_access, 3}
-    ];
+    [{description, 0}, {check_user_login, 2}, {check_vhost_access, 2},
+     {check_resource_access, 3}];
 behaviour_info(_Other) ->
     undefined.
+
+-endif.
diff --git a/src/rabbit_auth_backend_internal.erl b/src/rabbit_auth_backend_internal.erl
index 086a90b4..7b9df81e 100644
--- a/src/rabbit_auth_backend_internal.erl
+++ b/src/rabbit_auth_backend_internal.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_auth_backend_internal).
@@ -32,8 +32,6 @@
          vhost_perms_info_keys/0, user_perms_info_keys/0,
          user_vhost_perms_info_keys/0]).
 
--include("rabbit_auth_backend_spec.hrl").
-
 -ifdef(use_specs).
 
 -type(regexp() :: binary()).
diff --git a/src/rabbit_auth_mechanism.erl b/src/rabbit_auth_mechanism.erl
index 897199ee..eda6a743 100644
--- a/src/rabbit_auth_mechanism.erl
+++ b/src/rabbit_auth_mechanism.erl
@@ -11,36 +11,46 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_auth_mechanism).
 
+-ifdef(use_specs).
+
+%% A description.
+-callback description() -> [proplist:property()].
+
+%% If this mechanism is enabled, should it be offered for a given socket?
+%% (primarily so EXTERNAL can be SSL-only)
+-callback should_offer(rabbit_net:socket()) -> boolean().
+
+%% Called before authentication starts. Should create a state
+%% object to be passed through all the stages of authentication.
+-callback init(rabbit_net:socket()) -> any().
+
+%% Handle a stage of authentication. Possible responses:
+%% {ok, User}
+%%     Authentication succeeded, and here's the user record.
+%% {challenge, Challenge, NextState}
+%%     Another round is needed. Here's the state I want next time.
+%% {protocol_error, Msg, Args}
+%%     Client got the protocol wrong. Log and die.
+%% {refused, Msg, Args}
+%%     Client failed authentication. Log and die.
+-callback handle_response(binary(), any()) ->
+    {'ok', rabbit_types:user()} |
+    {'challenge', binary(), any()} |
+    {'protocol_error', string(), [any()]} |
+    {'refused', string(), [any()]}.
+
+-else.
+
 -export([behaviour_info/1]).
 
 behaviour_info(callbacks) ->
-    [
-     %% A description.
-     {description, 0},
-
-     %% If this mechanism is enabled, should it be offered for a given socket?
-     %% (primarily so EXTERNAL can be SSL-only)
-     {should_offer, 1},
-
-     %% Called before authentication starts. Should create a state
-     %% object to be passed through all the stages of authentication.
-     {init, 1},
-
-     %% Handle a stage of authentication. Possible responses:
-     %% {ok, User}
-     %%     Authentication succeeded, and here's the user record.
-     %% {challenge, Challenge, NextState}
-     %%     Another round is needed. Here's the state I want next time.
-     %% {protocol_error, Msg, Args}
-     %%     Client got the protocol wrong. Log and die.
-     %% {refused, Msg, Args}
-     %%     Client failed authentication. Log and die.
-     {handle_response, 2}
-    ];
+    [{description, 0}, {should_offer, 1}, {init, 1}, {handle_response, 2}];
 behaviour_info(_Other) ->
     undefined.
+
+-endif.
diff --git a/src/rabbit_auth_mechanism_amqplain.erl b/src/rabbit_auth_mechanism_amqplain.erl
index b8682a46..c0d86cd1 100644
--- a/src/rabbit_auth_mechanism_amqplain.erl
+++ b/src/rabbit_auth_mechanism_amqplain.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_auth_mechanism_amqplain).
@@ -21,8 +21,6 @@
 
 -export([description/0, should_offer/1, init/1, handle_response/2]).
 
--include("rabbit_auth_mechanism_spec.hrl").
-
 -rabbit_boot_step({?MODULE,
                    [{description, "auth mechanism amqplain"},
                     {mfa,         {rabbit_registry, register,
diff --git a/src/rabbit_auth_mechanism_cr_demo.erl b/src/rabbit_auth_mechanism_cr_demo.erl
index acbb6e48..5df1d5d7 100644
--- a/src/rabbit_auth_mechanism_cr_demo.erl
+++ b/src/rabbit_auth_mechanism_cr_demo.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_auth_mechanism_cr_demo).
@@ -21,8 +21,6 @@
 
 -export([description/0, should_offer/1, init/1, handle_response/2]).
 
--include("rabbit_auth_mechanism_spec.hrl").
-
 -rabbit_boot_step({?MODULE,
                    [{description, "auth mechanism cr-demo"},
                     {mfa,         {rabbit_registry, register,
diff --git a/src/rabbit_auth_mechanism_plain.erl b/src/rabbit_auth_mechanism_plain.erl
index 2448acb6..423170e1 100644
--- a/src/rabbit_auth_mechanism_plain.erl
+++ b/src/rabbit_auth_mechanism_plain.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_auth_mechanism_plain).
@@ -21,8 +21,6 @@
 
 -export([description/0, should_offer/1, init/1, handle_response/2]).
 
--include("rabbit_auth_mechanism_spec.hrl").
-
 -rabbit_boot_step({?MODULE,
                    [{description, "auth mechanism plain"},
                     {mfa,         {rabbit_registry, register,
diff --git a/src/rabbit_backing_queue.erl b/src/rabbit_backing_queue.erl
index c3b322ee..dc144a0e 100644
--- a/src/rabbit_backing_queue.erl
+++ b/src/rabbit_backing_queue.erl
@@ -11,161 +11,206 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_backing_queue).
 
+-ifdef(use_specs).
+
+%% We can't specify a per-queue ack/state with callback signatures
+-type(ack()   :: any()).
+-type(state() :: any()).
+
+-type(fetch_result(Ack) ::
+        ('empty' |
+         %% Message,                  IsDelivered, AckTag, Remaining_Len
+         {rabbit_types:basic_message(), boolean(), Ack, non_neg_integer()})).
+-type(attempt_recovery() :: boolean()).
+-type(purged_msg_count() :: non_neg_integer()).
+-type(async_callback() :: fun ((atom(), fun ((atom(), state()) -> state())) -> 'ok')).
+-type(duration() :: ('undefined' | 'infinity' | number())).
+
+-type(msg_fun() :: fun((rabbit_types:basic_message(), ack()) -> 'ok') |
+                   'undefined').
+-type(msg_pred() :: fun ((rabbit_types:message_properties()) -> boolean())).
+
+%% Called on startup with a list of durable queue names. The queues
+%% aren't being started at this point, but this call allows the
+%% backing queue to perform any checking necessary for the consistency
+%% of those queues, or initialise any other shared resources.
+-callback start([rabbit_amqqueue:name()]) -> 'ok'.
+
+%% Called to tear down any state/resources. NB: Implementations should
+%% not depend on this function being called on shutdown and instead
+%% should hook into the rabbit supervision hierarchy.
+-callback stop() -> 'ok'.
+
+%% Initialise the backing queue and its state.
+%%
+%% Takes
+%% 1. the amqqueue record
+%% 2. a boolean indicating whether the queue is an existing queue that
+%%    should be recovered
+%% 3. an asynchronous callback which accepts a function of type
+%%    backing-queue-state to backing-queue-state. This callback
+%%    function can be safely invoked from any process, which makes it
+%%    useful for passing messages back into the backing queue,
+%%    especially as the backing queue does not have control of its own
+%%    mailbox.
+-callback init(rabbit_types:amqqueue(), attempt_recovery(),
+               async_callback()) -> state().
+
+%% Called on queue shutdown when queue isn't being deleted.
+-callback terminate(any(), state()) -> state().
+
+%% Called when the queue is terminating and needs to delete all its
+%% content.
+-callback delete_and_terminate(any(), state()) -> state().
+
+%% Remove all messages in the queue, but not messages which have been
+%% fetched and are pending acks.
+-callback purge(state()) -> {purged_msg_count(), state()}.
+
+%% Publish a message.
+-callback publish(rabbit_types:basic_message(),
+                  rabbit_types:message_properties(), pid(), state()) ->
+    state().
+
+%% Called for messages which have already been passed straight
+%% out to a client. The queue will be empty for these calls
+%% (i.e. saves the round trip through the backing queue).
+-callback publish_delivered(true, rabbit_types:basic_message(),
+                            rabbit_types:message_properties(), pid(), state())
+                           -> {ack(), state()};
+                           (false, rabbit_types:basic_message(),
+                            rabbit_types:message_properties(), pid(), state())
+                           -> {undefined, state()}.
+
+%% Return ids of messages which have been confirmed since the last
+%% invocation of this function (or initialisation).
+%%
+%% Message ids should only appear in the result of drain_confirmed
+%% under the following circumstances:
+%%
+%% 1. The message appears in a call to publish_delivered/4 and the
+%%    first argument (ack_required) is false; or
+%% 2. The message is fetched from the queue with fetch/2 and the first
+%%    argument (ack_required) is false; or
+%% 3. The message is acked (ack/2 is called for the message); or
+%% 4. The message is fully fsync'd to disk in such a way that the
+%%    recovery of the message is guaranteed in the event of a crash of
+%%    this rabbit node (excluding hardware failure).
+%%
+%% In addition to the above conditions, a message id may only appear
+%% in the result of drain_confirmed if
+%% #message_properties.needs_confirming = true when the msg was
+%% published (through whichever means) to the backing queue.
+%%
+%% It is legal for the same message id to appear in the results of
+%% multiple calls to drain_confirmed, which means that the backing
+%% queue is not required to keep track of which messages it has
+%% already confirmed. The confirm will be issued to the publisher the
+%% first time the message id appears in the result of
+%% drain_confirmed. All subsequent appearances of that message id will
+%% be ignored.
+-callback drain_confirmed(state()) -> {[rabbit_guid:guid()], state()}.
+
+%% Drop messages from the head of the queue while the supplied predicate returns
+%% true. Also accepts a boolean parameter that determines whether the messages
+%% necessitate an ack or not. If they do, the function returns a list of
+%% messages with the respective acktags.
+-callback dropwhile(msg_pred(), true, state())
+                   -> {[{rabbit_types:basic_message(), ack()}], state()};
+                   (msg_pred(), false, state())
+                   -> {undefined, state()}.
+
+%% Produce the next message.
+-callback fetch(true,  state()) -> {fetch_result(ack()), state()};
+               (false, state()) -> {fetch_result(undefined), state()}.
+
+%% Acktags supplied are for messages which can now be forgotten
+%% about. Must return 1 msg_id per Ack, in the same order as Acks.
+-callback ack([ack()], state()) -> {[rabbit_guid:guid()], state()}.
+
+%% Acktags supplied are for messages which should be processed. The
+%% provided callback function is called with each message.
+-callback fold(msg_fun(), state(), [ack()]) -> state().
+
+%% Reinsert messages into the queue which have already been delivered
+%% and were pending acknowledgement.
+-callback requeue([ack()], state()) -> {[rabbit_guid:guid()], state()}.
+
+%% How long is my queue?
+-callback len(state()) -> non_neg_integer().
+
+%% Is my queue empty?
+-callback is_empty(state()) -> boolean().
+
+%% For the next three functions, the assumption is that you're
+%% monitoring something like the ingress and egress rates of the
+%% queue. The RAM duration is thus the length of time represented by
+%% the messages held in RAM given the current rates. If you want to
+%% ignore all of this stuff, then do so, and return 0 in
+%% ram_duration/1.
+
+%% The target is to have no more messages in RAM than indicated by the
+%% duration and the current queue rates.
+-callback set_ram_duration_target(duration(), state()) -> state().
+
+%% Optionally recalculate the duration internally (likely to be just
+%% update your internal rates), and report how many seconds the
+%% messages in RAM represent given the current rates of the queue.
+-callback ram_duration(state()) -> {duration(), state()}.
+
+%% Should 'timeout' be called as soon as the queue process can manage
+%% (either on an empty mailbox, or when a timer fires)?
+-callback needs_timeout(state()) -> 'false' | 'timed' | 'idle'.
+
+%% Called (eventually) after needs_timeout returns 'idle' or 'timed'.
+%% Note this may be called more than once for each 'idle' or 'timed'
+%% returned from needs_timeout
+-callback timeout(state()) -> state().
+
+%% Called immediately before the queue hibernates.
+-callback handle_pre_hibernate(state()) -> state().
+
+%% Exists for debugging purposes, to be able to expose state via
+%% rabbitmqctl list_queues backing_queue_status
+-callback status(state()) -> [{atom(), any()}].
+
+%% Passed a function to be invoked with the relevant backing queue's
+%% state. Useful for when the backing queue or other components need
+%% to pass functions into the backing queue.
+-callback invoke(atom(), fun ((atom(), A) -> A), state()) -> state().
+
+%% Called prior to a publish or publish_delivered call. Allows the BQ
+%% to signal that it's already seen this message (and in what capacity
+%% - i.e. was it published previously or discarded previously) and
+%% thus the message should be dropped.
+-callback is_duplicate(rabbit_types:basic_message(), state())
+                      -> {'false'|'published'|'discarded', state()}.
+
+%% Called to inform the BQ about messages which have reached the
+%% queue, but are not going to be further passed to BQ for some
+%% reason. Note that this is may be invoked for messages for which
+%% BQ:is_duplicate/2 has already returned {'published' | 'discarded',
+%% BQS}.
+-callback discard(rabbit_types:basic_message(), pid(), state()) -> state().
+
+-else.
+
 -export([behaviour_info/1]).
 
 behaviour_info(callbacks) ->
-    [
-     %% Called on startup with a list of durable queue names. The
-     %% queues aren't being started at this point, but this call
-     %% allows the backing queue to perform any checking necessary for
-     %% the consistency of those queues, or initialise any other
-     %% shared resources.
-     {start, 1},
-
-     %% Called to tear down any state/resources. NB: Implementations
-     %% should not depend on this function being called on shutdown
-     %% and instead should hook into the rabbit supervision hierarchy.
-     {stop, 0},
-
-     %% Initialise the backing queue and its state.
-     %%
-     %% Takes
-     %% 1. the amqqueue record
-     %% 2. a boolean indicating whether the queue is an existing queue
-     %%    that should be recovered
-     %% 3. an asynchronous callback which accepts a function of type
-     %%    backing-queue-state to backing-queue-state. This callback
-     %%    function can be safely invoked from any process, which
-     %%    makes it useful for passing messages back into the backing
-     %%    queue, especially as the backing queue does not have
-     %%    control of its own mailbox.
-     {init, 3},
-
-     %% Called on queue shutdown when queue isn't being deleted.
-     {terminate, 2},
-
-     %% Called when the queue is terminating and needs to delete all
-     %% its content.
-     {delete_and_terminate, 2},
-
-     %% Remove all messages in the queue, but not messages which have
-     %% been fetched and are pending acks.
-     {purge, 1},
-
-     %% Publish a message.
-     {publish, 4},
-
-     %% Called for messages which have already been passed straight
-     %% out to a client. The queue will be empty for these calls
-     %% (i.e. saves the round trip through the backing queue).
-     {publish_delivered, 5},
-
-     %% Return ids of messages which have been confirmed since
-     %% the last invocation of this function (or initialisation).
-     %%
-     %% Message ids should only appear in the result of
-     %% drain_confirmed under the following circumstances:
-     %%
-     %% 1. The message appears in a call to publish_delivered/4 and
-     %%    the first argument (ack_required) is false; or
-     %% 2. The message is fetched from the queue with fetch/2 and the
-     %%    first argument (ack_required) is false; or
-     %% 3. The message is acked (ack/2 is called for the message); or
-     %% 4. The message is fully fsync'd to disk in such a way that the
-     %%    recovery of the message is guaranteed in the event of a
-     %%    crash of this rabbit node (excluding hardware failure).
-     %%
-     %% In addition to the above conditions, a message id may only
-     %% appear in the result of drain_confirmed if
-     %% #message_properties.needs_confirming = true when the msg was
-     %% published (through whichever means) to the backing queue.
-     %%
-     %% It is legal for the same message id to appear in the results
-     %% of multiple calls to drain_confirmed, which means that the
-     %% backing queue is not required to keep track of which messages
-     %% it has already confirmed. The confirm will be issued to the
-     %% publisher the first time the message id appears in the result
-     %% of drain_confirmed. All subsequent appearances of that message
-     %% id will be ignored.
-     {drain_confirmed, 1},
-
-     %% Drop messages from the head of the queue while the supplied
-     %% predicate returns true.
-     {dropwhile, 2},
-
-     %% Produce the next message.
-     {fetch, 2},
-
-     %% Acktags supplied are for messages which can now be forgotten
-     %% about. Must return 1 msg_id per Ack, in the same order as Acks.
-     {ack, 2},
-
-     %% Reinsert messages into the queue which have already been
-     %% delivered and were pending acknowledgement.
-     {requeue, 2},
-
-     %% How long is my queue?
-     {len, 1},
-
-     %% Is my queue empty?
-     {is_empty, 1},
-
-     %% For the next three functions, the assumption is that you're
-     %% monitoring something like the ingress and egress rates of the
-     %% queue. The RAM duration is thus the length of time represented
-     %% by the messages held in RAM given the current rates. If you
-     %% want to ignore all of this stuff, then do so, and return 0 in
-     %% ram_duration/1.
-
-     %% The target is to have no more messages in RAM than indicated
-     %% by the duration and the current queue rates.
-     {set_ram_duration_target, 2},
-
-     %% Optionally recalculate the duration internally (likely to be
-     %% just update your internal rates), and report how many seconds
-     %% the messages in RAM represent given the current rates of the
-     %% queue.
-     {ram_duration, 1},
-
-     %% Should 'timeout' be called as soon as the queue process
-     %% can manage (either on an empty mailbox, or when a timer
-     %% fires)?
-     {needs_timeout, 1},
-
-     %% Called (eventually) after needs_timeout returns 'idle' or
-     %% 'timed'.  Note this may be called more than once for each
-     %% 'idle' or 'timed' returned from needs_timeout.
-     {timeout, 1},
-
-     %% Called immediately before the queue hibernates.
-     {handle_pre_hibernate, 1},
-
-     %% Exists for debugging purposes, to be able to expose state via
-     %% rabbitmqctl list_queues backing_queue_status
-     {status, 1},
-
-     %% Passed a function to be invoked with the relevant backing
-     %% queue's state. Useful for when the backing queue or other
-     %% components need to pass functions into the backing queue.
-     {invoke, 3},
-
-     %% Called prior to a publish or publish_delivered call. Allows
-     %% the BQ to signal that it's already seen this message (and in
-     %% what capacity - i.e. was it published previously or discarded
-     %% previously) and thus the message should be dropped.
-     {is_duplicate, 2},
-
-     %% Called to inform the BQ about messages which have reached the
-     %% queue, but are not going to be further passed to BQ for some
-     %% reason. Note that this is may be invoked for messages for
-     %% which BQ:is_duplicate/2 has already returned {'published' |
-     %% 'discarded', BQS}.
-     {discard, 3}
-    ];
+    [{start, 1}, {stop, 0}, {init, 3}, {terminate, 2},
+     {delete_and_terminate, 2}, {purge, 1}, {publish, 4},
+     {publish_delivered, 5}, {drain_confirmed, 1}, {dropwhile, 3},
+     {fetch, 2}, {ack, 2}, {fold, 3}, {requeue, 2}, {len, 1},
+     {is_empty, 1}, {set_ram_duration_target, 2}, {ram_duration, 1},
+     {needs_timeout, 1}, {timeout, 1}, {handle_pre_hibernate, 1},
+     {status, 1}, {invoke, 3}, {is_duplicate, 2}, {discard, 3}];
 behaviour_info(_Other) ->
     undefined.
+
+-endif.
diff --git a/src/rabbit_backing_queue_qc.erl b/src/rabbit_backing_queue_qc.erl
index c61184a6..a84800c0 100644
--- a/src/rabbit_backing_queue_qc.erl
+++ b/src/rabbit_backing_queue_qc.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2011-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2011-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_backing_queue_qc).
@@ -141,7 +141,7 @@ qc_drain_confirmed(#state{bqstate = BQ}) ->
     {call, ?BQMOD, drain_confirmed, [BQ]}.
 
 qc_dropwhile(#state{bqstate = BQ}) ->
-    {call, ?BQMOD, dropwhile, [fun dropfun/1, BQ]}.
+    {call, ?BQMOD, dropwhile, [fun dropfun/1, false, BQ]}.
 
 qc_is_empty(#state{bqstate = BQ}) ->
     {call, ?BQMOD, is_empty, [BQ]}.
@@ -267,10 +267,11 @@ next_state(S, Res, {call, ?BQMOD, drain_confirmed, _Args}) ->
     BQ1 = {call, erlang, element, [2, Res]},
     S#state{bqstate = BQ1};
 
-next_state(S, BQ1, {call, ?BQMOD, dropwhile, _Args}) ->
+next_state(S, Res, {call, ?BQMOD, dropwhile, _Args}) ->
+    BQ = {call, erlang, element, [2, Res]},
     #state{messages = Messages} = S,
     Msgs1 = drop_messages(Messages),
-    S#state{bqstate = BQ1, len = gb_trees:size(Msgs1), messages = Msgs1};
+    S#state{bqstate = BQ, len = gb_trees:size(Msgs1), messages = Msgs1};
 
 next_state(S, _Res, {call, ?BQMOD, is_empty, _Args}) ->
     S;
diff --git a/src/rabbit_basic.erl b/src/rabbit_basic.erl
index b266d366..734456d3 100644
--- a/src/rabbit_basic.erl
+++ b/src/rabbit_basic.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_basic).
@@ -19,7 +19,8 @@
 -include("rabbit_framing.hrl").
 
 -export([publish/4, publish/6, publish/1,
-         message/3, message/4, properties/1, delivery/4]).
+         message/3, message/4, properties/1, append_table_header/3,
+         extract_headers/1, map_headers/2, delivery/4, header_routes/1]).
 -export([build_content/2, from_content/1]).
 
 %%----------------------------------------------------------------------------
@@ -29,8 +30,9 @@
 -type(properties_input() ::
         (rabbit_framing:amqp_property_record() | [{atom(), any()}])).
 -type(publish_result() ::
-        ({ok, rabbit_router:routing_result(), [pid()]}
+        ({ok, rabbit_amqqueue:routing_result(), [pid()]}
          | rabbit_types:error('not_found'))).
+-type(headers() :: rabbit_framing:amqp_table() | 'undefined').
 
 -type(exchange_input() :: (rabbit_types:exchange() | rabbit_exchange:name())).
 -type(body_input() :: (binary() | [binary()])).
@@ -55,6 +57,17 @@
                         rabbit_types:ok_or_error2(rabbit_types:message(), any())).
 -spec(properties/1 ::
         (properties_input()) -> rabbit_framing:amqp_property_record()).
+
+-spec(append_table_header/3 ::
+        (binary(), rabbit_framing:amqp_table(), headers()) -> headers()).
+
+-spec(extract_headers/1 :: (rabbit_types:content()) -> headers()).
+
+-spec(map_headers/2 :: (fun((headers()) -> headers()), rabbit_types:content())
+                       -> rabbit_types:content()).
+
+-spec(header_routes/1 ::
+        (undefined | rabbit_framing:amqp_table()) -> [string()]).
 -spec(build_content/2 :: (rabbit_framing:amqp_property_record(),
                           binary() | [binary()]) -> rabbit_types:content()).
 -spec(from_content/1 :: (rabbit_types:content()) ->
@@ -88,8 +101,8 @@ publish(Delivery = #delivery{
     end.
 
 publish(X, Delivery) ->
-    {RoutingRes, DeliveredQPids} =
-        rabbit_router:deliver(rabbit_exchange:route(X, Delivery), Delivery),
+    Qs = rabbit_amqqueue:lookup(rabbit_exchange:route(X, Delivery)),
+    {RoutingRes, DeliveredQPids} = rabbit_amqqueue:deliver(Qs, Delivery),
     {ok, RoutingRes, DeliveredQPids}.
 
 delivery(Mandatory, Immediate, Message, MsgSeqNo) ->
@@ -139,7 +152,7 @@ message(XName, RoutingKey, #content{properties = Props} = DecodedContent) ->
         {ok, #basic_message{
            exchange_name = XName,
            content       = strip_header(DecodedContent, ?DELETED_HEADER),
-           id            = rabbit_guid:guid(),
+           id            = rabbit_guid:gen(),
            is_persistent = is_message_persistent(DecodedContent),
            routing_keys  = [RoutingKey |
                             header_routes(Props#'P_basic'.headers)]}}
@@ -166,11 +179,32 @@ properties(P) when is_list(P) ->
                         end
                 end, #'P_basic'{}, P).
 
+append_table_header(Name, Info, undefined) ->
+    append_table_header(Name, Info, []);
+append_table_header(Name, Info, Headers) ->
+    Prior = case rabbit_misc:table_lookup(Headers, Name) of
+                undefined          -> [];
+                {array, Existing}  -> Existing
+            end,
+    rabbit_misc:set_table_value(Headers, Name, array, [{table, Info} | Prior]).
+
+extract_headers(Content) ->
+    #content{properties = #'P_basic'{headers = Headers}} =
+        rabbit_binary_parser:ensure_content_decoded(Content),
+    Headers.
+
+map_headers(F, Content) ->
+    Content1 = rabbit_binary_parser:ensure_content_decoded(Content),
+    #content{properties = #'P_basic'{headers = Headers} = Props} = Content1,
+    Headers1 = F(Headers),
+    rabbit_binary_generator:clear_encoded_content(
+      Content1#content{properties = Props#'P_basic'{headers = Headers1}}).
+
 indexof(L, Element) -> indexof(L, Element, 1).
 
-indexof([], _Element, _N)              -> 0;
-indexof([Element | _Rest], Element, N) -> N;
-indexof([_ | Rest], Element, N)        -> indexof(Rest, Element, N + 1).
+indexof([],               _Element, _N) -> 0;
+indexof([Element | _Rest], Element,  N) -> N;
+indexof([_ | Rest],        Element,  N) -> indexof(Rest, Element, N + 1).
 
 is_message_persistent(#content{properties = #'P_basic'{
                                  delivery_mode = Mode}}) ->
@@ -190,6 +224,5 @@ header_routes(HeadersTable) ->
            {array, Routes} -> [Route || {longstr, Route} <- Routes];
            undefined       -> [];
            {Type, _Val}    -> throw({error, {unacceptable_type_in_header,
-                                             Type,
-                                             binary_to_list(HeaderKey)}})
+                                             binary_to_list(HeaderKey), Type}})
        end || HeaderKey <- ?ROUTING_HEADERS]).
diff --git a/src/rabbit_binary_generator.erl b/src/rabbit_binary_generator.erl
index 494f3203..d69376fb 100644
--- a/src/rabbit_binary_generator.erl
+++ b/src/rabbit_binary_generator.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_binary_generator).
diff --git a/src/rabbit_binary_parser.erl b/src/rabbit_binary_parser.erl
index f3ca4e98..5f0016b6 100644
--- a/src/rabbit_binary_parser.erl
+++ b/src/rabbit_binary_parser.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_binary_parser).
diff --git a/src/rabbit_binding.erl b/src/rabbit_binding.erl
index 0d221b05..bb44797e 100644
--- a/src/rabbit_binding.erl
+++ b/src/rabbit_binding.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_binding).
@@ -354,8 +354,8 @@ continue({[], Continuation}) -> continue(mnesia:select(Continuation)).
 
 %% For bulk operations we lock the tables we are operating on in order
 %% to reduce the time complexity. Without the table locks we end up
-%% with num_tables*num_bulk_bindings row-level locks. Takiing each
-%% lock takes time proportional to the number of existing locks, thus
+%% with num_tables*num_bulk_bindings row-level locks. Taking each lock
+%% takes time proportional to the number of existing locks, thus
 %% resulting in O(num_bulk_bindings^2) complexity.
 %%
 %% The locks need to be write locks since ultimately we end up
diff --git a/src/rabbit_channel.erl b/src/rabbit_channel.erl
index 9b2fe28c..22c6a223 100644
--- a/src/rabbit_channel.erl
+++ b/src/rabbit_channel.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_channel).
@@ -20,8 +20,8 @@
 
 -behaviour(gen_server2).
 
--export([start_link/10, do/2, do/3, flush/1, shutdown/1]).
--export([send_command/2, deliver/4, flushed/2, confirm/2]).
+-export([start_link/11, do/2, do/3, do_flow/3, flush/1, shutdown/1]).
+-export([send_command/2, deliver/4, flushed/2]).
 -export([list/0, info_keys/0, info/1, info/2, info_all/0, info_all/1]).
 -export([refresh_config_local/0, ready_for_close/1]).
 -export([force_event_refresh/0]).
@@ -33,12 +33,12 @@
 -export([list_local/0]).
 
 -record(ch, {state, protocol, channel, reader_pid, writer_pid, conn_pid,
-             limiter, tx_status, next_tag,
-             unacked_message_q, uncommitted_message_q, uncommitted_acks,
-             user, virtual_host, most_recently_declared_queue, queue_monitors,
-             consumer_mapping, blocking, queue_consumers, queue_collector_pid,
-             stats_timer, confirm_enabled, publish_seqno, unconfirmed_mq,
-             unconfirmed_qm, confirmed, capabilities, trace_state}).
+             conn_name, limiter, tx_status, next_tag, unacked_message_q,
+             uncommitted_message_q, uncommitted_acks, uncommitted_nacks, user,
+             virtual_host, most_recently_declared_queue, queue_monitors,
+             consumer_mapping, blocking, queue_consumers, delivering_queues,
+             queue_collector_pid, stats_timer, confirm_enabled, publish_seqno,
+             unconfirmed, confirmed, capabilities, trace_state}).
 
 -define(MAX_PERMISSION_CACHE_SIZE, 12).
 
@@ -56,6 +56,7 @@
 
 -define(CREATION_EVENT_KEYS,
         [pid,
+         name,
          connection,
          number,
          user,
@@ -71,13 +72,16 @@
 
 -type(channel_number() :: non_neg_integer()).
 
--spec(start_link/10 ::
-        (channel_number(), pid(), pid(), pid(), rabbit_types:protocol(),
-         rabbit_types:user(), rabbit_types:vhost(), rabbit_framing:amqp_table(),
+-spec(start_link/11 ::
+        (channel_number(), pid(), pid(), pid(), string(),
+         rabbit_types:protocol(), rabbit_types:user(), rabbit_types:vhost(),
+         rabbit_framing:amqp_table(),
          pid(), rabbit_limiter:token()) -> rabbit_types:ok_pid_or_error()).
 -spec(do/2 :: (pid(), rabbit_framing:amqp_method_record()) -> 'ok').
 -spec(do/3 :: (pid(), rabbit_framing:amqp_method_record(),
                rabbit_types:maybe(rabbit_types:content())) -> 'ok').
+-spec(do_flow/3 :: (pid(), rabbit_framing:amqp_method_record(),
+                    rabbit_types:maybe(rabbit_types:content())) -> 'ok').
 -spec(flush/1 :: (pid()) -> 'ok').
 -spec(shutdown/1 :: (pid()) -> 'ok').
 -spec(send_command/2 :: (pid(), rabbit_framing:amqp_method_record()) -> 'ok').
@@ -85,7 +89,6 @@
         (pid(), rabbit_types:ctag(), boolean(), rabbit_amqqueue:qmsg())
         -> 'ok').
 -spec(flushed/2 :: (pid(), pid()) -> 'ok').
--spec(confirm/2 ::(pid(), [non_neg_integer()]) -> 'ok').
 -spec(list/0 :: () -> [pid()]).
 -spec(list_local/0 :: () -> [pid()]).
 -spec(info_keys/0 :: () -> rabbit_types:info_keys()).
@@ -101,17 +104,21 @@
 
 %%----------------------------------------------------------------------------
 
-start_link(Channel, ReaderPid, WriterPid, ConnPid, Protocol, User, VHost,
-           Capabilities, CollectorPid, Limiter) ->
+start_link(Channel, ReaderPid, WriterPid, ConnPid, ConnName, Protocol, User,
+           VHost, Capabilities, CollectorPid, Limiter) ->
     gen_server2:start_link(
-      ?MODULE, [Channel, ReaderPid, WriterPid, ConnPid, Protocol, User,
-                VHost, Capabilities, CollectorPid, Limiter], []).
+      ?MODULE, [Channel, ReaderPid, WriterPid, ConnPid, ConnName, Protocol,
+                User, VHost, Capabilities, CollectorPid, Limiter], []).
 
 do(Pid, Method) ->
     do(Pid, Method, none).
 
 do(Pid, Method, Content) ->
-    gen_server2:cast(Pid, {method, Method, Content}).
+    gen_server2:cast(Pid, {method, Method, Content, noflow}).
+
+do_flow(Pid, Method, Content) ->
+    credit_flow:send(Pid),
+    gen_server2:cast(Pid, {method, Method, Content, flow}).
 
 flush(Pid) ->
     gen_server2:call(Pid, flush, infinity).
@@ -128,9 +135,6 @@ deliver(Pid, ConsumerTag, AckRequired, Msg) ->
 flushed(Pid, QPid) ->
     gen_server2:cast(Pid, {flushed, QPid}).
 
-confirm(Pid, MsgSeqNos) ->
-    gen_server2:cast(Pid, {confirm, MsgSeqNos, self()}).
-
 list() ->
     rabbit_misc:append_rpc_all_nodes(rabbit_mnesia:running_clustered_nodes(),
                                      rabbit_channel, list_local, []).
@@ -169,7 +173,7 @@ force_event_refresh() ->
 
 %%---------------------------------------------------------------------------
 
-init([Channel, ReaderPid, WriterPid, ConnPid, Protocol, User, VHost,
+init([Channel, ReaderPid, WriterPid, ConnPid, ConnName, Protocol, User, VHost,
       Capabilities, CollectorPid, Limiter]) ->
     process_flag(trap_exit, true),
     ok = pg_local:join(rabbit_channels, self()),
@@ -179,24 +183,26 @@ init([Channel, ReaderPid, WriterPid, ConnPid, Protocol, User, VHost,
                 reader_pid              = ReaderPid,
                 writer_pid              = WriterPid,
                 conn_pid                = ConnPid,
+                conn_name               = ConnName,
                 limiter                 = Limiter,
                 tx_status               = none,
                 next_tag                = 1,
                 unacked_message_q       = queue:new(),
                 uncommitted_message_q   = queue:new(),
                 uncommitted_acks        = [],
+                uncommitted_nacks       = [],
                 user                    = User,
                 virtual_host            = VHost,
                 most_recently_declared_queue = <<>>,
-                queue_monitors          = dict:new(),
+                queue_monitors          = pmon:new(),
                 consumer_mapping        = dict:new(),
                 blocking                = sets:new(),
                 queue_consumers         = dict:new(),
+                delivering_queues       = sets:new(),
                 queue_collector_pid     = CollectorPid,
                 confirm_enabled         = false,
                 publish_seqno           = 1,
-                unconfirmed_mq          = gb_trees:empty(),
-                unconfirmed_qm          = gb_trees:empty(),
+                unconfirmed             = dtree:empty(),
                 confirmed               = [],
                 capabilities            = Capabilities,
                 trace_state             = rabbit_trace:init(VHost)},
@@ -244,7 +250,12 @@ handle_call(refresh_config, _From, State = #ch{virtual_host = VHost}) ->
 handle_call(_Request, _From, State) ->
     noreply(State).
 
-handle_cast({method, Method, Content}, State) ->
+handle_cast({method, Method, Content, Flow},
+            State = #ch{reader_pid = Reader}) ->
+    case Flow of
+        flow   -> credit_flow:ack(Reader);
+        noflow -> ok
+    end,
     try handle_method(Method, Content, State) of
         {reply, Reply, NewState} ->
             ok = rabbit_writer:send_command(NewState#ch.writer_pid, Reply),
@@ -284,29 +295,19 @@ handle_cast({command, Msg}, State = #ch{writer_pid = WriterPid}) ->
 handle_cast({deliver, ConsumerTag, AckRequired,
              Msg = {_QName, QPid, _MsgId, Redelivered,
                     #basic_message{exchange_name = ExchangeName,
-                                   routing_keys = [RoutingKey | _CcRoutes],
-                                   content = Content}}},
-            State = #ch{writer_pid  = WriterPid,
-                        next_tag    = DeliveryTag,
-                        trace_state = TraceState}) ->
-    State1 = lock_message(AckRequired,
-                          ack_record(DeliveryTag, ConsumerTag, Msg),
-                          State),
-
-    M = #'basic.deliver'{consumer_tag = ConsumerTag,
-                         delivery_tag = DeliveryTag,
-                         redelivered = Redelivered,
-                         exchange = ExchangeName#resource.name,
-                         routing_key = RoutingKey},
-    rabbit_writer:send_command_and_notify(WriterPid, QPid, self(), M, Content),
-    State2 = maybe_incr_stats([{QPid, 1}], case AckRequired of
-                                               true  -> deliver;
-                                               false -> deliver_no_ack
-                                           end, State1),
-    State3 = maybe_incr_redeliver_stats(Redelivered, QPid, State2),
-    rabbit_trace:tap_trace_out(Msg, TraceState),
-    noreply(State3#ch{next_tag = DeliveryTag + 1});
-
+                                   routing_keys  = [RoutingKey | _CcRoutes],
+                                   content       = Content}}},
+            State = #ch{writer_pid = WriterPid,
+                        next_tag   = DeliveryTag}) ->
+    ok = rabbit_writer:send_command_and_notify(
+           WriterPid, QPid, self(),
+           #'basic.deliver'{consumer_tag = ConsumerTag,
+                            delivery_tag = DeliveryTag,
+                            redelivered  = Redelivered,
+                            exchange     = ExchangeName#resource.name,
+                            routing_key  = RoutingKey},
+           Content),
+    noreply(record_sent(ConsumerTag, AckRequired, Msg, State));
 
 handle_cast(force_event_refresh, State) ->
     rabbit_event:notify(channel_created, infos(?CREATION_EVENT_KEYS, State)),
@@ -315,6 +316,10 @@ handle_cast({confirm, MsgSeqNos, From}, State) ->
     State1 = #ch{confirmed = C} = confirm(MsgSeqNos, From, State),
     noreply([send_confirms], State1, case C of [] -> hibernate; _ -> 0 end).
 
+handle_info({bump_credit, Msg}, State) ->
+    credit_flow:handle_bump_msg(Msg),
+    noreply(State);
+
 handle_info(timeout, State) ->
     noreply(State);
 
@@ -327,9 +332,11 @@ handle_info({'DOWN', _MRef, process, QPid, Reason}, State) ->
     State1 = handle_publishing_queue_down(QPid, Reason, State),
     State2 = queue_blocked(QPid, State1),
     State3 = handle_consuming_queue_down(QPid, State2),
+    State4 = handle_delivering_queue_down(QPid, State3),
+    credit_flow:peer_down(QPid),
     erase_queue_stats(QPid),
-    noreply(State3#ch{queue_monitors =
-                          dict:erase(QPid, State3#ch.queue_monitors)});
+    noreply(State3#ch{queue_monitors = pmon:erase(
+                                         QPid, State4#ch.queue_monitors)});
 
 handle_info({'EXIT', _Pid, Reason}, State) ->
     {stop, Reason, State}.
@@ -527,7 +534,7 @@ queue_blocked(QPid, State = #ch{blocking = Blocking}) ->
                                  #'channel.flow_ok'{active = false});
                           _ -> ok
                       end,
-                 demonitor_queue(QPid, State#ch{blocking = Blocking1})
+                 State#ch{blocking = Blocking1}
     end.
 
 record_confirm(undefined, _, State) ->
@@ -542,46 +549,9 @@ record_confirms(MXs, State = #ch{confirmed = C}) ->
 
 confirm([], _QPid, State) ->
     State;
-confirm(MsgSeqNos, QPid, State) ->
-    {MXs, State1} = process_confirms(MsgSeqNos, QPid, false, State),
-    record_confirms(MXs, State1).
-
-process_confirms(MsgSeqNos, QPid, Nack, State) ->
-    lists:foldl(
-      fun(MsgSeqNo, {_MXs, _State = #ch{unconfirmed_mq = UMQ0}} = Acc) ->
-              case gb_trees:lookup(MsgSeqNo, UMQ0) of
-                  {value, XQ} -> remove_unconfirmed(MsgSeqNo, QPid, XQ,
-                                                    Acc, Nack);
-                  none        -> Acc
-              end
-      end, {[], State}, MsgSeqNos).
-
-remove_unconfirmed(MsgSeqNo, QPid, {XName, Qs},
-                   {MXs, State = #ch{unconfirmed_mq = UMQ,
-                                     unconfirmed_qm = UQM}},
-                   Nack) ->
-    State1 = case gb_trees:lookup(QPid, UQM) of
-                 {value, MsgSeqNos} ->
-                     MsgSeqNos1 = gb_sets:delete(MsgSeqNo, MsgSeqNos),
-                     case gb_sets:is_empty(MsgSeqNos1) of
-                         true  -> UQM1 = gb_trees:delete(QPid, UQM),
-                                  demonitor_queue(
-                                    QPid, State#ch{unconfirmed_qm = UQM1});
-                         false -> UQM1 = gb_trees:update(QPid, MsgSeqNos1, UQM),
-                                  State#ch{unconfirmed_qm = UQM1}
-                     end;
-                 none ->
-                     State
-             end,
-    Qs1 = gb_sets:del_element(QPid, Qs),
-    %% If QPid somehow died initiating a nack, clear the message from
-    %% internal data-structures.  Also, cleanup empty entries.
-    case (Nack orelse gb_sets:is_empty(Qs1)) of
-        true  -> UMQ1 = gb_trees:delete(MsgSeqNo, UMQ),
-                 {[{MsgSeqNo, XName} | MXs], State1#ch{unconfirmed_mq = UMQ1}};
-        false -> UMQ1 = gb_trees:update(MsgSeqNo, {XName, Qs1}, UMQ),
-                 {MXs, State1#ch{unconfirmed_mq = UMQ1}}
-    end.
+confirm(MsgSeqNos, QPid, State = #ch{unconfirmed = UC}) ->
+    {MXs, UC1} = dtree:take(MsgSeqNos, QPid, UC),
+    record_confirms(MXs, State#ch{unconfirmed = UC1}).
 
 handle_method(#'channel.open'{}, _, State = #ch{state = starting}) ->
     {reply, #'channel.open_ok'{}, State#ch{state = running}};
@@ -672,17 +642,17 @@ handle_method(#'basic.ack'{delivery_tag = DeliveryTag,
     State1 = State#ch{unacked_message_q = Remaining},
     {noreply,
      case TxStatus of
-         none        -> ack(Acked, State1);
+         none        -> ack(Acked, State1),
+                        State1;
          in_progress -> State1#ch{uncommitted_acks =
                                       Acked ++ State1#ch.uncommitted_acks}
      end};
 
 handle_method(#'basic.get'{queue = QueueNameBin,
                            no_ack = NoAck},
-              _, State = #ch{writer_pid  = WriterPid,
-                             conn_pid    = ConnPid,
-                             next_tag    = DeliveryTag,
-                             trace_state = TraceState}) ->
+              _, State = #ch{writer_pid = WriterPid,
+                             conn_pid   = ConnPid,
+                             next_tag   = DeliveryTag}) ->
     QueueName = expand_queue_name_shortcut(QueueNameBin, State),
     check_read_permitted(QueueName, State),
     case rabbit_amqqueue:with_exclusive_access_or_die(
@@ -691,26 +661,18 @@ handle_method(#'basic.get'{queue = QueueNameBin,
         {ok, MessageCount,
          Msg = {_QName, QPid, _MsgId, Redelivered,
                 #basic_message{exchange_name = ExchangeName,
-                               routing_keys = [RoutingKey | _CcRoutes],
-                               content = Content}}} ->
-            State1 = lock_message(not(NoAck),
-                                  ack_record(DeliveryTag, none, Msg),
-                                  State),
-            State2 = maybe_incr_stats([{QPid, 1}], case NoAck of
-                                                       true  -> get_no_ack;
-                                                       false -> get
-                                                   end, State1),
-            State3 = maybe_incr_redeliver_stats(Redelivered, QPid, State2),
-            rabbit_trace:tap_trace_out(Msg, TraceState),
+                               routing_keys  = [RoutingKey | _CcRoutes],
+                               content       = Content}}} ->
             ok = rabbit_writer:send_command(
                    WriterPid,
-                   #'basic.get_ok'{delivery_tag = DeliveryTag,
-                                   redelivered = Redelivered,
-                                   exchange = ExchangeName#resource.name,
-                                   routing_key = RoutingKey,
+                   #'basic.get_ok'{delivery_tag  = DeliveryTag,
+                                   redelivered   = Redelivered,
+                                   exchange      = ExchangeName#resource.name,
+                                   routing_key   = RoutingKey,
                                    message_count = MessageCount},
                    Content),
-            {noreply, State3#ch{next_tag = DeliveryTag + 1}};
+            State1 = monitor_delivering_queue(NoAck, QPid, State),
+            {noreply, record_sent(none, not(NoAck), Msg, State1)};
         empty ->
             {reply, #'basic.get_empty'{}, State}
     end;
@@ -730,7 +692,8 @@ handle_method(#'basic.consume'{queue        = QueueNameBin,
             check_read_permitted(QueueName, State),
             ActualConsumerTag =
                 case ConsumerTag of
-                    <<>>  -> rabbit_guid:binstring_guid("amq.ctag");
+                    <<>>  -> rabbit_guid:binary(rabbit_guid:gen_secure(),
+                                                "amq.ctag");
                     Other -> Other
                 end,
 
@@ -747,10 +710,10 @@ handle_method(#'basic.consume'{queue        = QueueNameBin,
                                        consumer_tag = ActualConsumerTag})),
                             Q}
                    end) of
-                {ok, Q} ->
-                    State1 = State#ch{consumer_mapping =
-                                          dict:store(ActualConsumerTag, Q,
-                                                     ConsumerMapping)},
+                {ok, Q = #amqqueue{pid = QPid}} ->
+                    CM1 = dict:store(ActualConsumerTag, Q, ConsumerMapping),
+                    State1 = monitor_delivering_queue(
+                               NoAck, QPid, State#ch{consumer_mapping = CM1}),
                     {noreply,
                      case NoWait of
                          true  -> consumer_monitor(ActualConsumerTag, State1);
@@ -787,9 +750,8 @@ handle_method(#'basic.cancel'{consumer_tag = ConsumerTag,
                                        false -> dict:store(QPid, CTags1, QCons)
                                    end
                 end,
-            NewState = demonitor_queue(
-                         Q, State#ch{consumer_mapping = ConsumerMapping1,
-                                     queue_consumers  = QCons1}),
+            NewState = State#ch{consumer_mapping = ConsumerMapping1,
+                                queue_consumers  = QCons1},
             %% In order to ensure that no more messages are sent to
             %% the consumer after the cancel_ok has been sent, we get
             %% the queue process to send the cancel_ok on our
@@ -799,9 +761,7 @@ handle_method(#'basic.cancel'{consumer_tag = ConsumerTag,
                    fun () -> {error, not_found} end,
                    fun () ->
                            rabbit_amqqueue:basic_cancel(
-                             Q, self(), ConsumerTag,
-                             ok_msg(NoWait, #'basic.cancel_ok'{
-                                      consumer_tag = ConsumerTag}))
+                             Q, self(), ConsumerTag, ok_msg(NoWait, OkMsg))
                    end) of
                 ok ->
                     {noreply, NewState};
@@ -960,7 +920,8 @@ handle_method(#'queue.declare'{queue       = QueueNameBin,
                 false -> none
             end,
     ActualNameBin = case QueueNameBin of
-                        <<>>  -> rabbit_guid:binstring_guid("amq.gen");
+                        <<>>  -> rabbit_guid:binary(rabbit_guid:gen_secure(),
+                                                    "amq.gen");
                         Other -> check_name('queue', Other)
                     end,
     QueueName = rabbit_misc:r(VHostPath, queue, ActualNameBin),
@@ -977,7 +938,7 @@ handle_method(#'queue.declare'{queue       = QueueNameBin,
         {error, not_found} ->
             case rabbit_amqqueue:declare(QueueName, Durable, AutoDelete,
                                          Args, Owner) of
-                {new, Q = #amqqueue{}} ->
+                {new, #amqqueue{pid = QPid}} ->
                     %% We need to notify the reader within the channel
                     %% process so that we can be sure there are no
                     %% outstanding exclusive queues being declared as
@@ -985,7 +946,7 @@ handle_method(#'queue.declare'{queue       = QueueNameBin,
                     ok = case Owner of
                              none -> ok;
                              _    -> rabbit_queue_collector:register(
-                                       CollectorPid, Q)
+                                       CollectorPid, QPid)
                          end,
                     return_queue_declare_ok(QueueName, NoWait, 0, 0, State);
                 {existing, _Q} ->
@@ -1068,19 +1029,26 @@ handle_method(#'tx.commit'{}, _, #ch{tx_status = none}) ->
     rabbit_misc:protocol_error(
       precondition_failed, "channel is not transactional", []);
 
-handle_method(#'tx.commit'{}, _, State = #ch{uncommitted_message_q = TMQ,
-                                             uncommitted_acks      = TAL}) ->
-    State1 = new_tx(ack(TAL, rabbit_misc:queue_fold(fun deliver_to_queues/2,
-                                                    State, TMQ))),
-    {noreply, maybe_complete_tx(State1#ch{tx_status = committing})};
+handle_method(#'tx.commit'{}, _,
+              State = #ch{uncommitted_message_q = TMQ,
+                          uncommitted_acks      = TAL,
+                          uncommitted_nacks     = TNL,
+                          limiter               = Limiter}) ->
+    State1 = rabbit_misc:queue_fold(fun deliver_to_queues/2, State, TMQ),
+    ack(TAL, State1),
+    lists:foreach(
+      fun({Requeue, Acked}) -> reject(Requeue, Acked, Limiter) end, TNL),
+    {noreply, maybe_complete_tx(new_tx(State1#ch{tx_status = committing}))};
 
 handle_method(#'tx.rollback'{}, _, #ch{tx_status = none}) ->
     rabbit_misc:protocol_error(
       precondition_failed, "channel is not transactional", []);
 
 handle_method(#'tx.rollback'{}, _, State = #ch{unacked_message_q = UAMQ,
-                                               uncommitted_acks  = TAL}) ->
-    UAMQ1 = queue:from_list(lists:usort(TAL ++ queue:to_list(UAMQ))),
+                                               uncommitted_acks  = TAL,
+                                               uncommitted_nacks = TNL}) ->
+    TNL1 = lists:append([L || {_, L} <- TNL]),
+    UAMQ1 = queue:from_list(lists:usort(TAL ++ TNL1 ++ queue:to_list(UAMQ))),
     {reply, #'tx.rollback_ok'{}, new_tx(State#ch{unacked_message_q = UAMQ1})};
 
 handle_method(#'confirm.select'{}, _, #ch{tx_status = in_progress}) ->
@@ -1111,10 +1079,7 @@ handle_method(#'channel.flow'{active = false}, _,
     ok = rabbit_limiter:block(Limiter1),
     case consumer_queues(Consumers) of
         []    -> {reply, #'channel.flow_ok'{active = false}, State1};
-        QPids -> State2 = lists:foldl(fun monitor_queue/2,
-                                      State1#ch{blocking =
-                                                    sets:from_list(QPids)},
-                                      QPids),
+        QPids -> State2 = State1#ch{blocking = sets:from_list(QPids)},
                  ok = rabbit_amqqueue:flush_all(QPids, self()),
                  {noreply, State2}
     end;
@@ -1127,6 +1092,7 @@ handle_method(_MethodRecord, _Content, _State) ->
 
 consumer_monitor(ConsumerTag,
                  State = #ch{consumer_mapping = ConsumerMapping,
+                             queue_monitors   = QMons,
                              queue_consumers  = QCons,
                              capabilities     = Capabilities}) ->
     case rabbit_misc:table_lookup(
@@ -1139,59 +1105,27 @@ consumer_monitor(ConsumerTag,
                                  end,
                                  gb_sets:singleton(ConsumerTag),
                                  QCons),
-            monitor_queue(QPid, State#ch{queue_consumers = QCons1});
+            State#ch{queue_monitors  = pmon:monitor(QPid, QMons),
+                     queue_consumers = QCons1};
         _ ->
             State
     end.
 
-monitor_queue(QPid, State = #ch{queue_monitors = QMons}) ->
-    case (not dict:is_key(QPid, QMons) andalso
-          queue_monitor_needed(QPid, State)) of
-        true  -> MRef = erlang:monitor(process, QPid),
-                 State#ch{queue_monitors = dict:store(QPid, MRef, QMons)};
-        false -> State
-    end.
-
-demonitor_queue(QPid, State = #ch{queue_monitors = QMons}) ->
-    case (dict:is_key(QPid, QMons) andalso
-          not queue_monitor_needed(QPid, State)) of
-        true  -> true = erlang:demonitor(dict:fetch(QPid, QMons)),
-                 State#ch{queue_monitors = dict:erase(QPid, QMons)};
-        false -> State
+monitor_delivering_queue(true, _QPid, State) ->
+    State;
+monitor_delivering_queue(false, QPid, State = #ch{queue_monitors    = QMons,
+                                                  delivering_queues = DQ}) ->
+    State#ch{queue_monitors    = pmon:monitor(QPid, QMons),
+             delivering_queues = sets:add_element(QPid, DQ)}.
+
+handle_publishing_queue_down(QPid, Reason, State = #ch{unconfirmed = UC}) ->
+    case rabbit_misc:is_abnormal_termination(Reason) of
+        true  -> {MXs, UC1} = dtree:take_all(QPid, UC),
+                 send_nacks(MXs, State#ch{unconfirmed = UC1});
+        false -> {MXs, UC1} = dtree:take(QPid, UC),
+                 record_confirms(MXs, State#ch{unconfirmed = UC1})
     end.
 
-queue_monitor_needed(QPid, #ch{queue_consumers = QCons,
-                               blocking        = Blocking,
-                               unconfirmed_qm  = UQM} = State) ->
-    StatsEnabled      = rabbit_event:stats_level(
-                          State, #ch.stats_timer) =:= fine,
-    ConsumerMonitored = dict:is_key(QPid, QCons),
-    QueueBlocked      = sets:is_element(QPid, Blocking),
-    ConfirmMonitored  = gb_trees:is_defined(QPid, UQM),
-    StatsEnabled or ConsumerMonitored or QueueBlocked or ConfirmMonitored.
-
-handle_publishing_queue_down(QPid, Reason, State = #ch{unconfirmed_qm = UQM}) ->
-    MsgSeqNos = case gb_trees:lookup(QPid, UQM) of
-                    {value, MsgSet} -> gb_sets:to_list(MsgSet);
-                    none            -> []
-                end,
-    %% We remove the MsgSeqNos from UQM before calling
-    %% process_confirms to prevent each MsgSeqNo being removed from
-    %% the set one by one which which would be inefficient
-    State1 = State#ch{unconfirmed_qm = gb_trees:delete_any(QPid, UQM)},
-    {Nack, SendFun} =
-        case Reason of
-            Reason when Reason =:= noproc; Reason =:= noconnection;
-                        Reason =:= normal; Reason =:= shutdown ->
-                {false, fun record_confirms/2};
-            {shutdown, _} ->
-                {false, fun record_confirms/2};
-            _ ->
-                {true,  fun send_nacks/2}
-        end,
-    {MXs, State2} = process_confirms(MsgSeqNos, QPid, Nack, State1),
-    SendFun(MXs, State2).
-
 handle_consuming_queue_down(QPid,
                             State = #ch{consumer_mapping = ConsumerMapping,
                                         queue_consumers  = QCons,
@@ -1210,6 +1144,9 @@ handle_consuming_queue_down(QPid,
     State#ch{consumer_mapping = ConsumerMapping1,
              queue_consumers  = dict:erase(QPid, QCons)}.
 
+handle_delivering_queue_down(QPid, State = #ch{delivering_queues = DQ}) ->
+    State#ch{delivering_queues = sets:del_element(QPid, DQ)}.
+
 binding_action(Fun, ExchangeNameBin, DestinationType, DestinationNameBin,
                RoutingKey, Arguments, ReturnMethod, NoWait,
                State = #ch{virtual_host = VHostPath,
@@ -1266,18 +1203,46 @@ basic_return(#basic_message{exchange_name = ExchangeName,
                            routing_key = RoutingKey},
            Content).
 
-reject(DeliveryTag, Requeue, Multiple, State = #ch{unacked_message_q = UAMQ}) ->
+reject(DeliveryTag, Requeue, Multiple,
+       State = #ch{unacked_message_q = UAMQ, tx_status = TxStatus}) ->
     {Acked, Remaining} = collect_acks(UAMQ, DeliveryTag, Multiple),
+    State1 = State#ch{unacked_message_q = Remaining},
+    {noreply,
+     case TxStatus of
+         none ->
+             reject(Requeue, Acked, State1#ch.limiter),
+             State1;
+         in_progress ->
+             State1#ch{uncommitted_nacks =
+                           [{Requeue, Acked} | State1#ch.uncommitted_nacks]}
+     end}.
+
+reject(Requeue, Acked, Limiter) ->
     ok = fold_per_queue(
            fun (QPid, MsgIds, ok) ->
                    rabbit_amqqueue:reject(QPid, MsgIds, Requeue, self())
            end, ok, Acked),
-    ok = notify_limiter(State#ch.limiter, Acked),
-    {noreply, State#ch{unacked_message_q = Remaining}}.
-
-ack_record(DeliveryTag, ConsumerTag,
-           _MsgStruct = {_QName, QPid, MsgId, _Redelivered, _Msg}) ->
-    {DeliveryTag, ConsumerTag, {QPid, MsgId}}.
+    ok = notify_limiter(Limiter, Acked).
+
+record_sent(ConsumerTag, AckRequired,
+            Msg = {_QName, QPid, MsgId, Redelivered, _Message},
+            State = #ch{unacked_message_q = UAMQ,
+                        next_tag          = DeliveryTag,
+                        trace_state       = TraceState}) ->
+    maybe_incr_stats([{QPid, 1}], case {ConsumerTag, AckRequired} of
+                                      {none,  true} -> get;
+                                      {none, false} -> get_no_ack;
+                                      {_   ,  true} -> deliver;
+                                      {_   , false} -> deliver_no_ack
+                                  end, State),
+    maybe_incr_redeliver_stats(Redelivered, QPid, State),
+    rabbit_trace:tap_trace_out(Msg, TraceState),
+    UAMQ1 = case AckRequired of
+                true  -> queue:in({DeliveryTag, ConsumerTag, {QPid, MsgId}},
+                                  UAMQ);
+                false -> UAMQ
+            end,
+    State#ch{unacked_message_q = UAMQ1, next_tag = DeliveryTag + 1}.
 
 collect_acks(Q, 0, true) ->
     {queue:to_list(Q), queue:new()};
@@ -1312,13 +1277,16 @@ ack(Acked, State) ->
     maybe_incr_stats(QIncs, ack, State).
 
 new_tx(State) -> State#ch{uncommitted_message_q = queue:new(),
-                          uncommitted_acks      = []}.
+                          uncommitted_acks      = [],
+                          uncommitted_nacks     = []}.
 
 notify_queues(State = #ch{state = closing}) ->
     {ok, State};
-notify_queues(State = #ch{consumer_mapping = Consumers}) ->
-    {rabbit_amqqueue:notify_down_all(consumer_queues(Consumers), self()),
-     State#ch{state = closing}}.
+notify_queues(State = #ch{consumer_mapping  = Consumers,
+                          delivering_queues = DQ }) ->
+    QPids = sets:to_list(
+              sets:union(sets:from_list(consumer_queues(Consumers)), DQ)),
+    {rabbit_amqqueue:notify_down_all(QPids, self()), State#ch{state = closing}}.
 
 fold_per_queue(_F, Acc, []) ->
     Acc;
@@ -1362,56 +1330,42 @@ deliver_to_queues({Delivery = #delivery{message    = Message = #basic_message{
                                                        exchange_name = XName},
                                         msg_seq_no = MsgSeqNo},
                    QNames}, State) ->
-    {RoutingRes, DeliveredQPids} = rabbit_router:deliver(QNames, Delivery),
-    State1 = process_routing_result(RoutingRes, DeliveredQPids,
-                                    XName, MsgSeqNo, Message, State),
+    {RoutingRes, DeliveredQPids} =
+        rabbit_amqqueue:deliver_flow(rabbit_amqqueue:lookup(QNames), Delivery),
+    State1 = State#ch{queue_monitors =
+                          pmon:monitor_all(DeliveredQPids,
+                                           State#ch.queue_monitors)},
+    State2 = process_routing_result(RoutingRes, DeliveredQPids,
+                                    XName, MsgSeqNo, Message, State1),
     maybe_incr_stats([{XName, 1} |
                       [{{QPid, XName}, 1} ||
-                          QPid <- DeliveredQPids]], publish, State1).
+                          QPid <- DeliveredQPids]], publish, State2),
+    State2.
 
 process_routing_result(unroutable,    _, XName,  MsgSeqNo, Msg, State) ->
     ok = basic_return(Msg, State, no_route),
-    record_confirm(MsgSeqNo, XName,
-                   maybe_incr_stats([{Msg#basic_message.exchange_name, 1}],
-                                    return_unroutable, State));
+    maybe_incr_stats([{Msg#basic_message.exchange_name, 1}],
+                     return_unroutable, State),
+    record_confirm(MsgSeqNo, XName, State);
 process_routing_result(not_delivered, _, XName,  MsgSeqNo, Msg, State) ->
     ok = basic_return(Msg, State, no_consumers),
-    record_confirm(MsgSeqNo, XName,
-                   maybe_incr_stats([{XName, 1}], return_not_delivered, State));
+    maybe_incr_stats([{XName, 1}], return_not_delivered, State),
+    record_confirm(MsgSeqNo, XName, State);
 process_routing_result(routed,       [], XName,  MsgSeqNo,   _, State) ->
     record_confirm(MsgSeqNo, XName, State);
 process_routing_result(routed,        _,     _, undefined,   _, State) ->
     State;
 process_routing_result(routed,    QPids, XName,  MsgSeqNo,   _, State) ->
-    #ch{unconfirmed_mq = UMQ} = State,
-    UMQ1 = gb_trees:insert(MsgSeqNo, {XName, gb_sets:from_list(QPids)}, UMQ),
-    SingletonSet = gb_sets:singleton(MsgSeqNo),
-    lists:foldl(
-      fun (QPid, State0 = #ch{unconfirmed_qm = UQM}) ->
-              case gb_trees:lookup(QPid, UQM) of
-                  {value, MsgSeqNos} ->
-                      MsgSeqNos1 = gb_sets:insert(MsgSeqNo, MsgSeqNos),
-                      UQM1 = gb_trees:update(QPid, MsgSeqNos1, UQM),
-                      State0#ch{unconfirmed_qm = UQM1};
-                  none ->
-                      UQM1 = gb_trees:insert(QPid, SingletonSet, UQM),
-                      monitor_queue(QPid, State0#ch{unconfirmed_qm = UQM1})
-              end
-      end, State#ch{unconfirmed_mq = UMQ1}, QPids).
-
-lock_message(true, MsgStruct, State = #ch{unacked_message_q = UAMQ}) ->
-    State#ch{unacked_message_q = queue:in(MsgStruct, UAMQ)};
-lock_message(false, _MsgStruct, State) ->
-    State.
+    State#ch{unconfirmed = dtree:insert(MsgSeqNo, QPids, XName,
+                                        State#ch.unconfirmed)}.
 
 send_nacks([], State) ->
     State;
 send_nacks(MXs, State = #ch{tx_status = none}) ->
-    MsgSeqNos = [ MsgSeqNo || {MsgSeqNo, _} <- MXs ],
-    coalesce_and_send(MsgSeqNos,
+    coalesce_and_send([MsgSeqNo || {MsgSeqNo, _} <- MXs],
                       fun(MsgSeqNo, Multiple) ->
                               #'basic.nack'{delivery_tag = MsgSeqNo,
-                                            multiple = Multiple}
+                                            multiple     = Multiple}
                       end, State);
 send_nacks(_, State) ->
     maybe_complete_tx(State#ch{tx_status = failed}).
@@ -1419,13 +1373,12 @@ send_nacks(_, State) ->
 send_confirms(State = #ch{tx_status = none, confirmed = []}) ->
     State;
 send_confirms(State = #ch{tx_status = none, confirmed = C}) ->
-    {MsgSeqNos, State1} =
-        lists:foldl(fun ({MsgSeqNo, ExchangeName}, {MSNs, State0}) ->
-                            {[MsgSeqNo | MSNs],
-                             maybe_incr_stats([{ExchangeName, 1}], confirm,
-                                              State0)}
-                    end, {[], State}, lists:append(C)),
-    send_confirms(MsgSeqNos, State1 #ch{confirmed = []});
+    MsgSeqNos =
+        lists:foldl(fun ({MsgSeqNo, XName}, MSNs) ->
+                            maybe_incr_stats([{XName, 1}], confirm, State),
+                            [MsgSeqNo | MSNs]
+                    end, [], lists:append(C)),
+    send_confirms(MsgSeqNos, State#ch{confirmed = []});
 send_confirms(State) ->
     maybe_complete_tx(State).
 
@@ -1442,11 +1395,11 @@ send_confirms(Cs, State) ->
                           end, State).
 
 coalesce_and_send(MsgSeqNos, MkMsgFun,
-                  State = #ch{writer_pid = WriterPid, unconfirmed_mq = UMQ}) ->
+                  State = #ch{writer_pid = WriterPid, unconfirmed = UC}) ->
     SMsgSeqNos = lists:usort(MsgSeqNos),
-    CutOff = case gb_trees:is_empty(UMQ) of
+    CutOff = case dtree:is_empty(UC) of
                  true  -> lists:last(SMsgSeqNos) + 1;
-                 false -> {SeqNo, _XQ} = gb_trees:smallest(UMQ), SeqNo
+                 false -> {SeqNo, _XName} = dtree:smallest(UC), SeqNo
              end,
     {Ms, Ss} = lists:splitwith(fun(X) -> X < CutOff end, SMsgSeqNos),
     case Ms of
@@ -1460,8 +1413,8 @@ coalesce_and_send(MsgSeqNos, MkMsgFun,
 
 maybe_complete_tx(State = #ch{tx_status = in_progress}) ->
     State;
-maybe_complete_tx(State = #ch{unconfirmed_mq = UMQ}) ->
-    case gb_trees:is_empty(UMQ) of
+maybe_complete_tx(State = #ch{unconfirmed = UC}) ->
+    case dtree:is_empty(UC) of
         false -> State;
         true  -> complete_tx(State#ch{confirmed = []})
     end.
@@ -1486,10 +1439,11 @@ i(user,           #ch{user             = User})    -> User#user.username;
 i(vhost,          #ch{virtual_host     = VHost})   -> VHost;
 i(transactional,  #ch{tx_status        = TE})      -> TE =/= none;
 i(confirm,        #ch{confirm_enabled  = CE})      -> CE;
+i(name,           State)                           -> name(State);
 i(consumer_count, #ch{consumer_mapping = ConsumerMapping}) ->
     dict:size(ConsumerMapping);
-i(messages_unconfirmed, #ch{unconfirmed_mq = UMQ}) ->
-    gb_trees:size(UMQ);
+i(messages_unconfirmed, #ch{unconfirmed = UC}) ->
+    dtree:size(UC);
 i(messages_unacknowledged, #ch{unacked_message_q = UAMQ}) ->
     queue:len(UAMQ);
 i(messages_uncommitted, #ch{uncommitted_message_q = TMQ}) ->
@@ -1503,28 +1457,26 @@ i(client_flow_blocked, #ch{limiter = Limiter}) ->
 i(Item, _) ->
     throw({bad_argument, Item}).
 
+name(#ch{conn_name = ConnName, channel = Channel}) ->
+    list_to_binary(rabbit_misc:format("~s (~p)", [ConnName, Channel])).
+
 maybe_incr_redeliver_stats(true, QPid, State) ->
     maybe_incr_stats([{QPid, 1}], redeliver, State);
-maybe_incr_redeliver_stats(_, _, State) ->
-    State.
+maybe_incr_redeliver_stats(_, _, _State) ->
+    ok.
 
 maybe_incr_stats(QXIncs, Measure, State) ->
     case rabbit_event:stats_level(State, #ch.stats_timer) of
-        fine -> lists:foldl(fun ({QX, Inc}, State0) ->
-                                    incr_stats(QX, Inc, Measure, State0)
-                            end, State, QXIncs);
-        _    -> State
+        fine -> [incr_stats(QX, Inc, Measure) || {QX, Inc} <- QXIncs];
+        _    -> ok
     end.
 
-incr_stats({QPid, _} = QX, Inc, Measure, State) ->
-    update_measures(queue_exchange_stats, QX, Inc, Measure),
-    monitor_queue(QPid, State);
-incr_stats(QPid, Inc, Measure, State) when is_pid(QPid) ->
-    update_measures(queue_stats, QPid, Inc, Measure),
-    monitor_queue(QPid, State);
-incr_stats(X, Inc, Measure, State) ->
-    update_measures(exchange_stats, X, Inc, Measure),
-    State.
+incr_stats({_, _} = QX, Inc, Measure) ->
+    update_measures(queue_exchange_stats, QX, Inc, Measure);
+incr_stats(QPid, Inc, Measure) when is_pid(QPid) ->
+    update_measures(queue_stats, QPid, Inc, Measure);
+incr_stats(X, Inc, Measure) ->
+    update_measures(exchange_stats, X, Inc, Measure).
 
 update_measures(Type, QX, Inc, Measure) ->
     Measures = case get({Type, QX}) of
diff --git a/src/rabbit_channel_sup.erl b/src/rabbit_channel_sup.erl
index a19b6bfd..bcb83851 100644
--- a/src/rabbit_channel_sup.erl
+++ b/src/rabbit_channel_sup.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_channel_sup).
@@ -32,10 +32,10 @@
 
 -type(start_link_args() ::
         {'tcp', rabbit_net:socket(), rabbit_channel:channel_number(),
-         non_neg_integer(), pid(), rabbit_types:protocol(), rabbit_types:user(),
-         rabbit_types:vhost(), rabbit_framing:amqp_table(),
+         non_neg_integer(), pid(), string(), rabbit_types:protocol(),
+         rabbit_types:user(), rabbit_types:vhost(), rabbit_framing:amqp_table(),
          pid()} |
-        {'direct', rabbit_channel:channel_number(), pid(),
+        {'direct', rabbit_channel:channel_number(), pid(), string(),
          rabbit_types:protocol(), rabbit_types:user(), rabbit_types:vhost(),
          rabbit_framing:amqp_table(), pid()}).
 
@@ -45,8 +45,8 @@
 
 %%----------------------------------------------------------------------------
 
-start_link({tcp, Sock, Channel, FrameMax, ReaderPid, Protocol, User, VHost,
-            Capabilities, Collector}) ->
+start_link({tcp, Sock, Channel, FrameMax, ReaderPid, ConnName, Protocol, User,
+            VHost, Capabilities, Collector}) ->
     {ok, SupPid} = supervisor2:start_link(?MODULE,
                                           {tcp, Sock, Channel, FrameMax,
                                            ReaderPid, Protocol}),
@@ -56,14 +56,14 @@ start_link({tcp, Sock, Channel, FrameMax, ReaderPid, Protocol, User, VHost,
         supervisor2:start_child(
           SupPid,
           {channel, {rabbit_channel, start_link,
-                     [Channel, ReaderPid, WriterPid, ReaderPid, Protocol,
-                      User, VHost, Capabilities, Collector,
+                     [Channel, ReaderPid, WriterPid, ReaderPid, ConnName,
+                      Protocol, User, VHost, Capabilities, Collector,
                       rabbit_limiter:make_token(LimiterPid)]},
            intrinsic, ?MAX_WAIT, worker, [rabbit_channel]}),
     {ok, AState} = rabbit_command_assembler:init(Protocol),
     {ok, SupPid, {ChannelPid, AState}};
-start_link({direct, Channel, ClientChannelPid, ConnPid, Protocol, User, VHost,
-            Capabilities, Collector}) ->
+start_link({direct, Channel, ClientChannelPid, ConnPid, ConnName, Protocol,
+            User, VHost, Capabilities, Collector}) ->
     {ok, SupPid} = supervisor2:start_link(?MODULE, direct),
     [LimiterPid] = supervisor2:find_child(SupPid, limiter),
     {ok, ChannelPid} =
@@ -71,7 +71,7 @@ start_link({direct, Channel, ClientChannelPid, ConnPid, Protocol, User, VHost,
           SupPid,
           {channel, {rabbit_channel, start_link,
                      [Channel, ClientChannelPid, ClientChannelPid, ConnPid,
-                      Protocol, User, VHost, Capabilities, Collector,
+                      ConnName, Protocol, User, VHost, Capabilities, Collector,
                       rabbit_limiter:make_token(LimiterPid)]},
            intrinsic, ?MAX_WAIT, worker, [rabbit_channel]}),
     {ok, SupPid, {ChannelPid, none}}.
diff --git a/src/rabbit_channel_sup_sup.erl b/src/rabbit_channel_sup_sup.erl
index e2561c80..995c41fb 100644
--- a/src/rabbit_channel_sup_sup.erl
+++ b/src/rabbit_channel_sup_sup.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_channel_sup_sup).
diff --git a/src/rabbit_client_sup.erl b/src/rabbit_client_sup.erl
index dfb400e3..c508f1b9 100644
--- a/src/rabbit_client_sup.erl
+++ b/src/rabbit_client_sup.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_client_sup).
@@ -28,8 +28,9 @@
 
 -ifdef(use_specs).
 
--spec(start_link/1 :: (mfa()) -> rabbit_types:ok_pid_or_error()).
--spec(start_link/2 :: ({'local', atom()}, mfa()) ->
+-spec(start_link/1 :: (rabbit_types:mfargs()) ->
+                           rabbit_types:ok_pid_or_error()).
+-spec(start_link/2 :: ({'local', atom()}, rabbit_types:mfargs()) ->
                            rabbit_types:ok_pid_or_error()).
 
 -endif.
diff --git a/src/rabbit_command_assembler.erl b/src/rabbit_command_assembler.erl
index a0953eab..adf6e417 100644
--- a/src/rabbit_command_assembler.erl
+++ b/src/rabbit_command_assembler.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_command_assembler).
diff --git a/src/rabbit_connection_sup.erl b/src/rabbit_connection_sup.erl
index b2aba2ee..12a532b6 100644
--- a/src/rabbit_connection_sup.erl
+++ b/src/rabbit_connection_sup.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_connection_sup).
diff --git a/src/rabbit_control.erl b/src/rabbit_control.erl
index 20486af5..0c3ac966 100644
--- a/src/rabbit_control.erl
+++ b/src/rabbit_control.erl
@@ -11,13 +11,13 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_control).
 -include("rabbit.hrl").
 
--export([start/0, stop/0, action/5, diagnostics/1]).
+-export([start/0, stop/0, action/5]).
 
 -define(RPC_TIMEOUT, infinity).
 -define(EXTERNAL_CHECK_INTERVAL, 1000).
@@ -26,6 +26,61 @@
 -define(NODE_OPT, "-n").
 -define(VHOST_OPT, "-p").
 
+-define(QUIET_DEF, {?QUIET_OPT, flag}).
+-define(NODE_DEF(Node), {?NODE_OPT, {option, Node}}).
+-define(VHOST_DEF, {?VHOST_OPT, {option, "/"}}).
+
+-define(GLOBAL_DEFS(Node), [?QUIET_DEF, ?NODE_DEF(Node)]).
+
+-define(COMMANDS,
+        [stop,
+         stop_app,
+         start_app,
+         wait,
+         reset,
+         force_reset,
+         rotate_logs,
+
+         cluster,
+         force_cluster,
+         cluster_status,
+
+         add_user,
+         delete_user,
+         change_password,
+         clear_password,
+         set_user_tags,
+         list_users,
+
+         add_vhost,
+         delete_vhost,
+         list_vhosts,
+         {set_permissions, [?VHOST_DEF]},
+         {clear_permissions, [?VHOST_DEF]},
+         {list_permissions, [?VHOST_DEF]},
+         list_user_permissions,
+
+         set_parameter,
+         clear_parameter,
+         list_parameters,
+
+         {list_queues, [?VHOST_DEF]},
+         {list_exchanges, [?VHOST_DEF]},
+         {list_bindings, [?VHOST_DEF]},
+         {list_connections, [?VHOST_DEF]},
+         list_channels,
+         {list_consumers, [?VHOST_DEF]},
+         status,
+         environment,
+         report,
+         eval,
+
+         close_connection,
+         {trace_on, [?VHOST_DEF]},
+         {trace_off, [?VHOST_DEF]},
+         set_vm_memory_high_watermark
+        ]).
+
 -define(GLOBAL_QUERIES,
         [{"Connections", rabbit_networking, connection_info_all,
           connection_info_keys},
@@ -49,7 +104,6 @@
         (atom(), node(), [string()], [{string(), any()}],
          fun ((string(), [any()]) -> 'ok'))
         -> 'ok').
--spec(diagnostics/1 :: (node()) -> [{string(), [any()]}]).
 -spec(usage/0 :: () -> no_return()).
 
 -endif.
@@ -58,19 +112,18 @@
 
 start() ->
     {ok, [[NodeStr|_]|_]} = init:get_argument(nodename),
-    {[Command0 | Args], Opts} =
-        case rabbit_misc:get_options([{flag, ?QUIET_OPT},
-                                      {option, ?NODE_OPT, NodeStr},
-                                      {option, ?VHOST_OPT, "/"}],
-                                     init:get_plain_arguments()) of
-            {[], _Opts}    -> usage();
-            CmdArgsAndOpts -> CmdArgsAndOpts
+    {Command, Opts, Args} =
+        case rabbit_misc:parse_arguments(?COMMANDS, ?GLOBAL_DEFS(NodeStr),
+                                         init:get_plain_arguments())
+        of
+            {ok, Res}  -> Res;
+            no_command -> print_error("could not recognise command", []),
+                          usage()
         end,
     Opts1 = [case K of
-                 ?NODE_OPT -> {?NODE_OPT, rabbit_misc:makenode(V)};
+                 ?NODE_OPT -> {?NODE_OPT, rabbit_nodes:make(V)};
                  _         -> {K, V}
              end || {K, V} <- Opts],
-    Command = list_to_atom(Command0),
     Quiet = proplists:get_bool(?QUIET_OPT, Opts1),
     Node = proplists:get_value(?NODE_OPT, Opts1),
     Inform = case Quiet of
@@ -79,6 +132,12 @@ start() ->
                                   io:format(Format ++ " ...~n", Args1)
                           end
              end,
+    PrintInvalidCommandError =
+        fun () ->
+                print_error("invalid command '~s'",
+                            [string:join([atom_to_list(Command) | Args], " ")])
+        end,
+
     %% The reason we don't use a try/catch here is that rpc:call turns
     %% thrown errors into normal return values
     case catch action(Command, Node, Args, Opts, Inform) of
@@ -88,9 +147,11 @@ start() ->
                 false -> io:format("...done.~n")
             end,
             rabbit_misc:quit(0);
-        {'EXIT', {function_clause, [{?MODULE, action, _} | _]}} ->
-            print_error("invalid command '~s'",
-                        [string:join([atom_to_list(Command) | Args], " ")]),
+        {'EXIT', {function_clause, [{?MODULE, action, _}    | _]}} -> %% < R15
+            PrintInvalidCommandError(),
+            usage();
+        {'EXIT', {function_clause, [{?MODULE, action, _, _} | _]}} -> %% >= R15
+            PrintInvalidCommandError(),
             usage();
         {'EXIT', {badarg, _}} ->
             print_error("invalid parameter: ~p", [Args]),
@@ -135,26 +196,7 @@ print_report0(Node, {Module, InfoFun, KeysFun}, VHostArg) ->
 print_error(Format, Args) -> fmt_stderr("Error: " ++ Format, Args).
 
 print_badrpc_diagnostics(Node) ->
-    [fmt_stderr(Fmt, Args) || {Fmt, Args} <- diagnostics(Node)].
-
-diagnostics(Node) ->
-    {_NodeName, NodeHost} = rabbit_misc:nodeparts(Node),
-    [{"diagnostics:", []},
-     case net_adm:names(NodeHost) of
-         {error, EpmdReason} ->
-             {"- unable to connect to epmd on ~s: ~w",
-              [NodeHost, EpmdReason]};
-         {ok, NamePorts} ->
-             {"- nodes and their ports on ~s: ~p",
-              [NodeHost, [{list_to_atom(Name), Port} ||
-                             {Name, Port} <- NamePorts]]}
-     end,
-     {"- current node: ~w", [node()]},
-     case init:get_argument(home) of
-         {ok, [[Home]]} -> {"- current node home dir: ~s", [Home]};
-         Other          -> {"- no current node home dir: ~p", [Other]}
-     end,
-     {"- current node cookie hash: ~s", [rabbit_misc:cookie_hash()]}].
+    fmt_stderr(rabbit_nodes:diagnostics([Node]), []).
 
 stop() ->
     ok.
@@ -206,7 +248,10 @@ action(force_cluster, Node, ClusterNodeSs, _Opts, Inform) ->
 
 action(wait, Node, [PidFile], _Opts, Inform) ->
     Inform("Waiting for ~p", [Node]),
-    wait_for_application(Node, PidFile, Inform);
+    wait_for_application(Node, PidFile, rabbit, Inform);
+action(wait, Node, [PidFile, App], _Opts, Inform) ->
+    Inform("Waiting for ~p on ~p", [App, Node]),
+    wait_for_application(Node, PidFile, list_to_atom(App), Inform);
 
 action(status, Node, [], _Opts, Inform) ->
     Inform("Status of node ~p", [Node]),
@@ -224,33 +269,33 @@ action(rotate_logs, Node, [], _Opts, Inform) ->
     Inform("Reopening logs for node ~p", [Node]),
     call(Node, {rabbit, rotate_logs, [""]});
 action(rotate_logs, Node, Args = [Suffix], _Opts, Inform) ->
-    Inform("Rotating logs to files with suffix ~p", [Suffix]),
+    Inform("Rotating logs to files with suffix \"~s\"", [Suffix]),
     call(Node, {rabbit, rotate_logs, Args});
 
 action(close_connection, Node, [PidStr, Explanation], _Opts, Inform) ->
-    Inform("Closing connection ~s", [PidStr]),
+    Inform("Closing connection \"~s\"", [PidStr]),
     rpc_call(Node, rabbit_networking, close_connection,
              [rabbit_misc:string_to_pid(PidStr), Explanation]);
 
 action(add_user, Node, Args = [Username, _Password], _Opts, Inform) ->
-    Inform("Creating user ~p", [Username]),
+    Inform("Creating user \"~s\"", [Username]),
     call(Node, {rabbit_auth_backend_internal, add_user, Args});
 
 action(delete_user, Node, Args = [_Username], _Opts, Inform) ->
-    Inform("Deleting user ~p", Args),
+    Inform("Deleting user \"~s\"", Args),
     call(Node, {rabbit_auth_backend_internal, delete_user, Args});
 
 action(change_password, Node, Args = [Username, _Newpassword], _Opts, Inform) ->
-    Inform("Changing password for user ~p", [Username]),
+    Inform("Changing password for user \"~s\"", [Username]),
     call(Node, {rabbit_auth_backend_internal, change_password, Args});
 
 action(clear_password, Node, Args = [Username], _Opts, Inform) ->
-    Inform("Clearing password for user ~p", [Username]),
+    Inform("Clearing password for user \"~s\"", [Username]),
     call(Node, {rabbit_auth_backend_internal, clear_password, Args});
 
 action(set_user_tags, Node, [Username | TagsStr], _Opts, Inform) ->
     Tags = [list_to_atom(T) || T <- TagsStr],
-    Inform("Setting tags for user ~p to ~p", [Username, Tags]),
+    Inform("Setting tags for user \"~s\" to ~p", [Username, Tags]),
     rpc_call(Node, rabbit_auth_backend_internal, set_tags,
              [list_to_binary(Username), Tags]);
 
@@ -261,11 +306,11 @@ action(list_users, Node, [], _Opts, Inform) ->
       rabbit_auth_backend_internal:user_info_keys());
 
 action(add_vhost, Node, Args = [_VHostPath], _Opts, Inform) ->
-    Inform("Creating vhost ~p", Args),
+    Inform("Creating vhost \"~s\"", Args),
     call(Node, {rabbit_vhost, add, Args});
 
 action(delete_vhost, Node, Args = [_VHostPath], _Opts, Inform) ->
-    Inform("Deleting vhost ~p", Args),
+    Inform("Deleting vhost \"~s\"", Args),
     call(Node, {rabbit_vhost, delete, Args});
 
 action(list_vhosts, Node, Args, _Opts, Inform) ->
@@ -327,12 +372,12 @@ action(list_consumers, Node, _Args, Opts, Inform) ->
 
 action(trace_on, Node, [], Opts, Inform) ->
     VHost = proplists:get_value(?VHOST_OPT, Opts),
-    Inform("Starting tracing for vhost ~p", [VHost]),
+    Inform("Starting tracing for vhost \"~s\"", [VHost]),
     rpc_call(Node, rabbit_trace, start, [list_to_binary(VHost)]);
 
 action(trace_off, Node, [], Opts, Inform) ->
     VHost = proplists:get_value(?VHOST_OPT, Opts),
-    Inform("Stopping tracing for vhost ~p", [VHost]),
+    Inform("Stopping tracing for vhost \"~s\"", [VHost]),
     rpc_call(Node, rabbit_trace, stop, [list_to_binary(VHost)]);
 
 action(set_vm_memory_high_watermark, Node, [Arg], _Opts, Inform) ->
@@ -340,28 +385,47 @@ action(set_vm_memory_high_watermark, Node, [Arg], _Opts, Inform) ->
                              0 -> Arg ++ ".0";
                              _ -> Arg
                          end),
-    Inform("Setting memory threshhold on ~p to ~p", [Node, Frac]),
+    Inform("Setting memory threshold on ~p to ~p", [Node, Frac]),
     rpc_call(Node, vm_memory_monitor, set_vm_memory_high_watermark, [Frac]);
 
 action(set_permissions, Node, [Username, CPerm, WPerm, RPerm], Opts, Inform) ->
     VHost = proplists:get_value(?VHOST_OPT, Opts),
-    Inform("Setting permissions for user ~p in vhost ~p", [Username, VHost]),
+    Inform("Setting permissions for user \"~s\" in vhost \"~s\"",
+           [Username, VHost]),
     call(Node, {rabbit_auth_backend_internal, set_permissions,
                 [Username, VHost, CPerm, WPerm, RPerm]});
 
 action(clear_permissions, Node, [Username], Opts, Inform) ->
     VHost = proplists:get_value(?VHOST_OPT, Opts),
-    Inform("Clearing permissions for user ~p in vhost ~p", [Username, VHost]),
+    Inform("Clearing permissions for user \"~s\" in vhost \"~s\"",
+           [Username, VHost]),
     call(Node, {rabbit_auth_backend_internal, clear_permissions,
                 [Username, VHost]});
 
 action(list_permissions, Node, [], Opts, Inform) ->
     VHost = proplists:get_value(?VHOST_OPT, Opts),
-    Inform("Listing permissions in vhost ~p", [VHost]),
+    Inform("Listing permissions in vhost \"~s\"", [VHost]),
     display_info_list(call(Node, {rabbit_auth_backend_internal,
                              list_vhost_permissions, [VHost]}),
                       rabbit_auth_backend_internal:vhost_perms_info_keys());
 
+action(set_parameter, Node, [Component, Key, Value], _Opts, Inform) ->
+    Inform("Setting runtime parameter ~p for component ~p to ~p",
+           [Key, Component, Value]),
+    rpc_call(Node, rabbit_runtime_parameters, parse_set,
+             [list_to_binary(Component), list_to_binary(Key), Value]);
+
+action(clear_parameter, Node, [Component, Key], _Opts, Inform) ->
+    Inform("Clearing runtime parameter ~p for component ~p", [Key, Component]),
+    rpc_call(Node, rabbit_runtime_parameters, clear, [list_to_binary(Component),
+                                                      list_to_binary(Key)]);
+
+action(list_parameters, Node, Args = [], _Opts, Inform) ->
+    Inform("Listing runtime parameters", []),
+    display_info_list(
+      rpc_call(Node, rabbit_runtime_parameters, list_formatted, Args),
+      rabbit_runtime_parameters:info_keys());
+
 action(report, Node, _Args, _Opts, Inform) ->
     io:format("Reporting server status on ~p~n~n", [erlang:universaltime()]),
     [begin ok = action(Action, N, [], [], Inform), io:nl() end ||
@@ -391,17 +455,17 @@ action(eval, Node, [Expr], _Opts, _Inform) ->
 
 %%----------------------------------------------------------------------------
 
-wait_for_application(Node, PidFile, Inform) ->
+wait_for_application(Node, PidFile, Application, Inform) ->
     Pid = read_pid_file(PidFile, true),
     Inform("pid is ~s", [Pid]),
-    wait_for_application(Node, Pid).
+    wait_for_application(Node, Pid, Application).
 
-wait_for_application(Node, Pid) ->
+wait_for_application(Node, Pid, Application) ->
     case process_up(Pid) of
-        true  -> case rabbit:is_running(Node) of
+        true  -> case rabbit_nodes:is_running(Node, Application) of
                      true  -> ok;
                      false -> timer:sleep(?EXTERNAL_CHECK_INTERVAL),
-                              wait_for_application(Node, Pid)
+                              wait_for_application(Node, Pid, Application)
                  end;
         false -> {error, process_not_running}
     end.
diff --git a/src/rabbit_direct.erl b/src/rabbit_direct.erl
index 6f9a4650..c07ad832 100644
--- a/src/rabbit_direct.erl
+++ b/src/rabbit_direct.erl
@@ -11,13 +11,13 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_direct).
 
 -export([boot/0, force_event_refresh/0, list/0, connect/5,
-         start_channel/8, disconnect/2]).
+         start_channel/9, disconnect/2]).
 %% Internal
 -export([list_local/0]).
 
@@ -36,10 +36,10 @@
                     rabbit_event:event_props()) ->
                         {'ok', {rabbit_types:user(),
                                 rabbit_framing:amqp_table()}}).
--spec(start_channel/8 ::
-        (rabbit_channel:channel_number(), pid(), pid(), rabbit_types:protocol(),
-         rabbit_types:user(), rabbit_types:vhost(), rabbit_framing:amqp_table(),
-         pid()) -> {'ok', pid()}).
+-spec(start_channel/9 ::
+        (rabbit_channel:channel_number(), pid(), pid(), string(),
+         rabbit_types:protocol(), rabbit_types:user(), rabbit_types:vhost(),
+         rabbit_framing:amqp_table(), pid()) -> {'ok', pid()}).
 
 -spec(disconnect/2 :: (pid(), rabbit_event:event_props()) -> 'ok').
 
@@ -47,16 +47,10 @@
 
 %%----------------------------------------------------------------------------
 
-boot() ->
-    {ok, _} =
-        supervisor2:start_child(
-          rabbit_sup,
-          {rabbit_direct_client_sup,
-           {rabbit_client_sup, start_link,
+boot() -> rabbit_sup:start_supervisor_child(
+            rabbit_direct_client_sup, rabbit_client_sup,
             [{local, rabbit_direct_client_sup},
-             {rabbit_channel_sup, start_link, []}]},
-           transient, infinity, supervisor, [rabbit_client_sup]}),
-    ok.
+             {rabbit_channel_sup, start_link, []}]).
 
 force_event_refresh() ->
     [Pid ! force_event_refresh || Pid<- list()],
@@ -92,13 +86,13 @@ connect(Username, VHost, Protocol, Pid, Infos) ->
             {error, broker_not_found_on_node}
     end.
 
-start_channel(Number, ClientChannelPid, ConnPid, Protocol, User, VHost,
-              Capabilities, Collector) ->
+start_channel(Number, ClientChannelPid, ConnPid, ConnName, Protocol, User,
+              VHost, Capabilities, Collector) ->
     {ok, _, {ChannelPid, _}} =
         supervisor2:start_child(
           rabbit_direct_client_sup,
-          [{direct, Number, ClientChannelPid, ConnPid, Protocol, User, VHost,
-            Capabilities, Collector}]),
+          [{direct, Number, ClientChannelPid, ConnPid, ConnName, Protocol,
+            User, VHost, Capabilities, Collector}]),
     {ok, ChannelPid}.
 
 disconnect(Pid, Infos) ->
diff --git a/src/rabbit_disk_monitor.erl b/src/rabbit_disk_monitor.erl
new file mode 100644
index 00000000..b1750b61
--- /dev/null
+++ b/src/rabbit_disk_monitor.erl
@@ -0,0 +1,196 @@
+%% The contents of this file are subject to the Mozilla Public License
+%% Version 1.1 (the "License"); you may not use this file except in
+%% compliance with the License. You may obtain a copy of the License
+%% at http://www.mozilla.org/MPL/
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and
+%% limitations under the License.
+%%
+%% The Original Code is RabbitMQ.
+%%
+%% The Initial Developer of the Original Code is VMware, Inc.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
+%%
+
+-module(rabbit_disk_monitor).
+
+-behaviour(gen_server).
+
+-export([start_link/1]).
+
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2,
+         terminate/2, code_change/3]).
+
+-export([get_disk_free_limit/0, set_disk_free_limit/1, get_check_interval/0,
+         set_check_interval/1, get_disk_free/0]).
+
+-define(SERVER, ?MODULE).
+-define(DEFAULT_DISK_CHECK_INTERVAL, 60000).
+
+-record(state, {dir,
+                limit,
+                timeout,
+                timer,
+                alarmed
+               }).
+
+%%----------------------------------------------------------------------------
+
+-ifdef(use_specs).
+
+-type(disk_free_limit() :: (integer() | {'mem_relative', float()})).
+-spec(start_link/1 :: (disk_free_limit()) -> rabbit_types:ok_pid_or_error()).
+-spec(get_disk_free_limit/0 :: () -> integer()).
+-spec(set_disk_free_limit/1 :: (disk_free_limit()) -> 'ok').
+-spec(get_check_interval/0 :: () -> integer()).
+-spec(set_check_interval/1 :: (integer()) -> 'ok').
+-spec(get_disk_free/0 :: () -> (integer() | 'unknown')).
+
+-endif.
+
+%%----------------------------------------------------------------------------
+%% Public API
+%%----------------------------------------------------------------------------
+
+get_disk_free_limit() ->
+    gen_server:call(?MODULE, get_disk_free_limit, infinity).
+
+set_disk_free_limit(Limit) ->
+    gen_server:call(?MODULE, {set_disk_free_limit, Limit}, infinity).
+
+get_check_interval() ->
+    gen_server:call(?MODULE, get_check_interval, infinity).
+
+set_check_interval(Interval) ->
+    gen_server:call(?MODULE, {set_check_interval, Interval}, infinity).
+
+get_disk_free() ->
+    gen_server:call(?MODULE, get_disk_free, infinity).
+
+%%----------------------------------------------------------------------------
+%% gen_server callbacks
+%%----------------------------------------------------------------------------
+
+start_link(Args) ->
+    gen_server:start_link({local, ?SERVER}, ?MODULE, [Args], []).
+
+init([Limit]) ->
+    TRef = start_timer(?DEFAULT_DISK_CHECK_INTERVAL),
+    Dir = dir(),
+    State = #state { dir     = Dir,
+                     timeout = ?DEFAULT_DISK_CHECK_INTERVAL,
+                     timer   = TRef,
+                     alarmed = false},
+    case {catch get_disk_free(Dir),
+          vm_memory_monitor:get_total_memory()} of
+        {N1, N2} when is_integer(N1), is_integer(N2) ->
+            {ok, set_disk_limits(State, Limit)};
+        Err ->
+            rabbit_log:info("Disabling disk free space monitoring "
+                            "on unsupported platform: ~p~n", [Err]),
+            {stop, unsupported_platform}
+    end.
+
+handle_call(get_disk_free_limit, _From, State) ->
+    {reply, interpret_limit(State#state.limit), State};
+
+handle_call({set_disk_free_limit, Limit}, _From, State) ->
+    {reply, ok, set_disk_limits(State, Limit)};
+
+handle_call(get_check_interval, _From, State) ->
+    {reply, State#state.timeout, State};
+
+handle_call({set_check_interval, Timeout}, _From, State) ->
+    {ok, cancel} = timer:cancel(State#state.timer),
+    {reply, ok, State#state{timeout = Timeout, timer = start_timer(Timeout)}};
+
+handle_call(get_disk_free, _From, State = #state { dir = Dir }) ->
+    {reply, get_disk_free(Dir), State};
+
+handle_call(_Request, _From, State) ->
+    {noreply, State}.
+
+handle_cast(_Request, State) ->
+    {noreply, State}.
+
+handle_info(update, State) ->
+    {noreply, internal_update(State)};
+
+handle_info(_Info, State) ->
+    {noreply, State}.
+
+terminate(_Reason, _State) ->
+    ok.
+
+code_change(_OldVsn, State, _Extra) ->
+    {ok, State}.
+
+%%----------------------------------------------------------------------------
+%% Server Internals
+%%----------------------------------------------------------------------------
+
+% the partition / drive containing this directory will be monitored
+dir() -> rabbit_mnesia:dir().
+
+set_disk_limits(State, Limit) ->
+    State1 = State#state { limit = Limit },
+    rabbit_log:info("Disk free limit set to ~pMB~n",
+                    [trunc(interpret_limit(Limit) / 1048576)]),
+    internal_update(State1).
+
+internal_update(State = #state { limit   = Limit,
+                                 dir     = Dir,
+                                 alarmed = Alarmed}) ->
+    CurrentFreeBytes = get_disk_free(Dir),
+    LimitBytes = interpret_limit(Limit),
+    NewAlarmed = CurrentFreeBytes < LimitBytes,
+    case {Alarmed, NewAlarmed} of
+        {false, true} ->
+            emit_update_info("exceeded", CurrentFreeBytes, LimitBytes),
+            alarm_handler:set_alarm({{resource_limit, disk, node()}, []});
+        {true, false} ->
+            emit_update_info("below limit", CurrentFreeBytes, LimitBytes),
+            alarm_handler:clear_alarm({resource_limit, disk, node()});
+        _ ->
+            ok
+    end,
+    State #state {alarmed = NewAlarmed}.
+
+get_disk_free(Dir) ->
+    get_disk_free(Dir, os:type()).
+
+get_disk_free(Dir, {unix, Sun})
+  when Sun =:= sunos; Sun =:= sunos4; Sun =:= solaris ->
+    parse_free_unix(rabbit_misc:os_cmd("/usr/bin/df -k " ++ Dir));
+get_disk_free(Dir, {unix, _}) ->
+    parse_free_unix(rabbit_misc:os_cmd("/bin/df -kP " ++ Dir));
+get_disk_free(Dir, {win32, _}) ->
+    parse_free_win32(os:cmd("dir /-C /W \"" ++ Dir ++ [$"]));
+get_disk_free(_, _) ->
+    unknown.
+
+parse_free_unix(CommandResult) ->
+    [_, Stats | _] = string:tokens(CommandResult, "\n"),
+    [_FS, _Total, _Used, Free | _] = string:tokens(Stats, " \t"),
+    list_to_integer(Free) * 1024.
+
+parse_free_win32(CommandResult) ->
+    LastLine = lists:last(string:tokens(CommandResult, "\r\n")),
+    [_, _Dir, Free, "bytes", "free"] = string:tokens(LastLine, " "),
+    list_to_integer(Free).
+
+interpret_limit({mem_relative, R}) ->
+    round(R * vm_memory_monitor:get_total_memory());
+interpret_limit(L) ->
+    L.
+
+emit_update_info(State, CurrentFree, Limit) ->
+    rabbit_log:info(
+      "Disk free space limit now ~s. Free bytes:~p Limit:~p~n",
+      [State, CurrentFree, Limit]).
+
+start_timer(Timeout) ->
+    {ok, TRef} = timer:send_interval(Timeout, update),
+    TRef.
diff --git a/src/rabbit_error_logger.erl b/src/rabbit_error_logger.erl
index 6e29ace7..f1672f4e 100644
--- a/src/rabbit_error_logger.erl
+++ b/src/rabbit_error_logger.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_error_logger).
diff --git a/src/rabbit_error_logger_file_h.erl b/src/rabbit_error_logger_file_h.erl
index 7b6e07c1..042ab23c 100644
--- a/src/rabbit_error_logger_file_h.erl
+++ b/src/rabbit_error_logger_file_h.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_error_logger_file_h).
diff --git a/src/rabbit_event.erl b/src/rabbit_event.erl
index 5ae40c78..3f1b20fe 100644
--- a/src/rabbit_event.erl
+++ b/src/rabbit_event.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_event).
@@ -139,6 +139,6 @@ notify_if(false, _Type, _Props) -> ok.
 notify(Type, Props) ->
     %% TODO: switch to os:timestamp() when we drop support for
     %% Erlang/OTP < R13B01
-    gen_event:notify(rabbit_event, #event{type = Type,
-                                          props = Props,
-                                          timestamp = now()}).
+    gen_event:notify(?MODULE, #event{type      = Type,
+                                     props     = Props,
+                                     timestamp = now()}).
diff --git a/src/rabbit_exchange.erl b/src/rabbit_exchange.erl
index a15b9be4..910a89b4 100644
--- a/src/rabbit_exchange.erl
+++ b/src/rabbit_exchange.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_exchange).
@@ -242,6 +242,11 @@ info_all(VHostPath) -> map(VHostPath, fun (X) -> info(X) end).
 
 info_all(VHostPath, Items) -> map(VHostPath, fun (X) -> info(X, Items) end).
 
+%% Optimisation
+route(#exchange{name = #resource{name = <<"">>, virtual_host = VHost}},
+      #delivery{message = #basic_message{routing_keys = RKs}}) ->
+    [rabbit_misc:r(VHost, queue, RK) || RK <- lists:usort(RKs)];
+
 route(X = #exchange{name = XName}, Delivery) ->
     route1(Delivery, {queue:from_list([X]), XName, []}).
 
@@ -355,11 +360,21 @@ peek_serial(XName) ->
         _                                  -> undefined
     end.
 
+invalid_module(T) ->
+    rabbit_log:warning(
+      "Could not find exchange type ~s.~n", [T]),
+    put({xtype_to_module, T}, rabbit_exchange_type_invalid),
+    rabbit_exchange_type_invalid.
+
 %% Used with atoms from records; e.g., the type is expected to exist.
 type_to_module(T) ->
     case get({xtype_to_module, T}) of
-        undefined -> {ok, Module} = rabbit_registry:lookup_module(exchange, T),
-                     put({xtype_to_module, T}, Module),
-                     Module;
-        Module    -> Module
+        undefined ->
+            case rabbit_registry:lookup_module(exchange, T) of
+                {ok, Module}       -> put({xtype_to_module, T}, Module),
+                                      Module;
+                {error, not_found} -> invalid_module(T)
+            end;
+        Module ->
+            Module
     end.
diff --git a/src/rabbit_exchange_type.erl b/src/rabbit_exchange_type.erl
index ab3d00dc..1027570c 100644
--- a/src/rabbit_exchange_type.erl
+++ b/src/rabbit_exchange_type.erl
@@ -11,44 +11,62 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_exchange_type).
 
--export([behaviour_info/1]).
+-ifdef(use_specs).
 
-behaviour_info(callbacks) ->
-    [
-     {description, 0},
+-type(tx() :: 'transaction' | 'none').
+-type(serial() :: pos_integer() | tx()).
+
+-callback description() -> [proplist:property()].
+
+%% Should Rabbit ensure that all binding events that are
+%% delivered to an individual exchange can be serialised? (they
+%% might still be delivered out of order, but there'll be a
+%% serial number).
+-callback serialise_events() -> boolean().
 
-     %% Should Rabbit ensure that all binding events that are
-     %% delivered to an individual exchange can be serialised? (they
-     %% might still be delivered out of order, but there'll be a
-     %% serial number).
-     {serialise_events, 0},
+%% The no_return is there so that we can have an "invalid" exchange
+%% type (see rabbit_exchange_type_invalid).
+-callback route(rabbit_types:exchange(), rabbit_types:delivery()) ->
+    rabbit_router:match_result().
 
-     {route, 2},
+%% called BEFORE declaration, to check args etc; may exit with #amqp_error{}
+-callback validate(rabbit_types:exchange()) -> 'ok'.
 
-     %% called BEFORE declaration, to check args etc; may exit with #amqp_error{}
-     {validate, 1},
+%% called after declaration and recovery
+-callback create(tx(), rabbit_types:exchange()) -> 'ok'.
 
-     %% called after declaration and recovery
-     {create, 2},
+%% called after exchange (auto)deletion.
+-callback delete(tx(), rabbit_types:exchange(), [rabbit_types:binding()]) ->
+    'ok'.
 
-     %% called after exchange (auto)deletion.
-     {delete, 3},
+%% called after a binding has been added or recovered
+-callback add_binding(serial(), rabbit_types:exchange(),
+                      rabbit_types:binding()) -> 'ok'.
 
-     %% called after a binding has been added or recovered
-     {add_binding, 3},
+%% called after bindings have been deleted.
+-callback remove_bindings(serial(), rabbit_types:exchange(),
+                          [rabbit_types:binding()]) -> 'ok'.
 
-     %% called after bindings have been deleted.
-     {remove_bindings, 3},
+%% called when comparing exchanges for equivalence - should return ok or
+%% exit with #amqp_error{}
+-callback assert_args_equivalence (rabbit_types:exchange(),
+                                   rabbit_framing:amqp_table()) ->
+    'ok' | rabbit_types:connection_exit().
 
-     %% called when comparing exchanges for equivalence - should return ok or
-     %% exit with #amqp_error{}
-     {assert_args_equivalence, 2}
+-else.
 
-    ];
+-export([behaviour_info/1]).
+
+behaviour_info(callbacks) ->
+    [{description, 0}, {serialise_events, 0}, {route, 2}, {validate, 1},
+     {create, 2}, {delete, 3}, {add_binding, 3}, {remove_bindings, 3},
+     {assert_args_equivalence, 2}];
 behaviour_info(_Other) ->
     undefined.
+
+-endif.
diff --git a/src/rabbit_exchange_type_direct.erl b/src/rabbit_exchange_type_direct.erl
index b485e31f..cdec1cb9 100644
--- a/src/rabbit_exchange_type_direct.erl
+++ b/src/rabbit_exchange_type_direct.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_exchange_type_direct).
@@ -22,7 +22,6 @@
 -export([description/0, serialise_events/0, route/2]).
 -export([validate/1, create/2, delete/3,
          add_binding/3, remove_bindings/3, assert_args_equivalence/2]).
--include("rabbit_exchange_type_spec.hrl").
 
 -rabbit_boot_step({?MODULE,
                    [{description, "exchange type direct"},
diff --git a/src/rabbit_exchange_type_fanout.erl b/src/rabbit_exchange_type_fanout.erl
index 3c029722..a64f2c29 100644
--- a/src/rabbit_exchange_type_fanout.erl
+++ b/src/rabbit_exchange_type_fanout.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_exchange_type_fanout).
@@ -22,7 +22,6 @@
 -export([description/0, serialise_events/0, route/2]).
 -export([validate/1, create/2, delete/3, add_binding/3,
          remove_bindings/3, assert_args_equivalence/2]).
--include("rabbit_exchange_type_spec.hrl").
 
 -rabbit_boot_step({?MODULE,
                    [{description, "exchange type fanout"},
diff --git a/src/rabbit_exchange_type_headers.erl b/src/rabbit_exchange_type_headers.erl
index f09e4aae..61917d8f 100644
--- a/src/rabbit_exchange_type_headers.erl
+++ b/src/rabbit_exchange_type_headers.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_exchange_type_headers).
@@ -23,7 +23,6 @@
 -export([description/0, serialise_events/0, route/2]).
 -export([validate/1, create/2, delete/3, add_binding/3,
          remove_bindings/3, assert_args_equivalence/2]).
--include("rabbit_exchange_type_spec.hrl").
 
 -rabbit_boot_step({?MODULE,
                    [{description, "exchange type headers"},
diff --git a/src/rabbit_exchange_type_invalid.erl b/src/rabbit_exchange_type_invalid.erl
new file mode 100644
index 00000000..82d27960
--- /dev/null
+++ b/src/rabbit_exchange_type_invalid.erl
@@ -0,0 +1,46 @@
+%% The contents of this file are subject to the Mozilla Public License
+%% Version 1.1 (the "License"); you may not use this file except in
+%% compliance with the License. You may obtain a copy of the License
+%% at http://www.mozilla.org/MPL/
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and
+%% limitations under the License.
+%%
+%% The Original Code is RabbitMQ.
+%%
+%% The Initial Developer of the Original Code is VMware, Inc.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
+%%
+
+-module(rabbit_exchange_type_invalid).
+-include("rabbit.hrl").
+
+-behaviour(rabbit_exchange_type).
+
+-export([description/0, serialise_events/0, route/2]).
+-export([validate/1, create/2, delete/3,
+         add_binding/3, remove_bindings/3, assert_args_equivalence/2]).
+
+description() ->
+    [{name, <<"invalid">>},
+     {description,
+      <<"Dummy exchange type, to be used when the intended one is not found.">>
+     }].
+
+serialise_events() -> false.
+
+route(#exchange{name = Name, type = Type}, _) ->
+    rabbit_misc:protocol_error(
+      precondition_failed,
+      "Cannot route message through ~s: exchange type ~s not found",
+      [rabbit_misc:rs(Name), Type]).
+
+validate(_X) -> ok.
+create(_Tx, _X) -> ok.
+delete(_Tx, _X, _Bs) -> ok.
+add_binding(_Tx, _X, _B) -> ok.
+remove_bindings(_Tx, _X, _Bs) -> ok.
+assert_args_equivalence(X, Args) ->
+    rabbit_exchange:assert_args_equivalence(X, Args).
diff --git a/src/rabbit_exchange_type_topic.erl b/src/rabbit_exchange_type_topic.erl
index 348655b1..3160fdf4 100644
--- a/src/rabbit_exchange_type_topic.erl
+++ b/src/rabbit_exchange_type_topic.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_exchange_type_topic).
@@ -23,7 +23,6 @@
 -export([description/0, serialise_events/0, route/2]).
 -export([validate/1, create/2, delete/3, add_binding/3,
          remove_bindings/3, assert_args_equivalence/2]).
--include("rabbit_exchange_type_spec.hrl").
 
 -rabbit_boot_step({?MODULE,
                    [{description, "exchange type topic"},
@@ -52,6 +51,7 @@ validate(_X) -> ok.
 create(_Tx, _X) -> ok.
 
 delete(transaction, #exchange{name = X}, _Bs) ->
+    trie_remove_all_nodes(X),
     trie_remove_all_edges(X),
     trie_remove_all_bindings(X),
     ok;
@@ -63,59 +63,26 @@ add_binding(transaction, _Exchange, Binding) ->
 add_binding(none, _Exchange, _Binding) ->
     ok.
 
-remove_bindings(transaction, #exchange{name = X}, Bs) ->
-    %% The remove process is split into two distinct phases. In the
-    %% first phase we gather the lists of bindings and edges to
-    %% delete, then in the second phase we process all the
-    %% deletions. This is to prevent interleaving of read/write
-    %% operations in mnesia that can adversely affect performance.
-    {ToDelete, Paths} =
-       lists:foldl(
-         fun(#binding{source = S, key = K, destination = D}, {Acc, PathAcc}) ->
-                 Path = [{FinalNode, _} | _] =
-                     follow_down_get_path(S, split_topic_key(K)),
-                 {[{FinalNode, D} | Acc],
-                  decrement_bindings(X, Path, maybe_add_path(X, Path, PathAcc))}
-         end, {[], gb_trees:empty()}, Bs),
-
-    [trie_remove_binding(X, FinalNode, D) || {FinalNode, D} <- ToDelete],
-    [trie_remove_edge(X, Parent, Node, W) ||
-        {Node, {Parent, W, {0, 0}}} <- gb_trees:to_list(Paths)],
+remove_bindings(transaction, _X, Bs) ->
+    %% See rabbit_binding:lock_route_tables for the rationale for
+    %% taking table locks.
+    case Bs of
+        [_] -> ok;
+        _   -> [mnesia:lock({table, T}, write) ||
+                   T <- [rabbit_topic_trie_node,
+                         rabbit_topic_trie_edge,
+                         rabbit_topic_trie_binding]]
+    end,
+    [begin
+         Path = [{FinalNode, _} | _] =
+             follow_down_get_path(X, split_topic_key(K)),
+         trie_remove_binding(X, FinalNode, D),
+         remove_path_if_empty(X, Path)
+     end ||  #binding{source = X, key = K, destination = D} <- Bs],
     ok;
 remove_bindings(none, _X, _Bs) ->
     ok.
 
-maybe_add_path(_X, [{root, none}], PathAcc) ->
-    PathAcc;
-maybe_add_path(X, [{Node, W}, {Parent, _} | _], PathAcc) ->
-    case gb_trees:is_defined(Node, PathAcc) of
-        true  -> PathAcc;
-        false -> gb_trees:insert(Node, {Parent, W, {trie_binding_count(X, Node),
-                                                    trie_child_count(X, Node)}},
-                                 PathAcc)
-    end.
-
-decrement_bindings(X, Path, PathAcc) ->
-    with_path_acc(X, fun({Bindings, Edges}) -> {Bindings - 1, Edges} end,
-                  Path, PathAcc).
-
-decrement_edges(X, Path, PathAcc) ->
-    with_path_acc(X, fun({Bindings, Edges}) -> {Bindings, Edges - 1} end,
-                  Path, PathAcc).
-
-with_path_acc(_X, _Fun, [{root, none}], PathAcc) ->
-    PathAcc;
-with_path_acc(X, Fun, [{Node, _} | ParentPath], PathAcc) ->
-    {Parent, W, Counts} = gb_trees:get(Node, PathAcc),
-    NewCounts = Fun(Counts),
-    NewPathAcc = gb_trees:update(Node, {Parent, W, NewCounts}, PathAcc),
-    case NewCounts of
-        {0, 0} -> decrement_edges(X, ParentPath,
-                                  maybe_add_path(X, ParentPath, NewPathAcc));
-        _      -> NewPathAcc
-    end.
-
-
 assert_args_equivalence(X, Args) ->
     rabbit_exchange:assert_args_equivalence(X, Args).
 
@@ -183,6 +150,16 @@ follow_down(X, CurNode, AccFun, Acc, Words = [W | RestW]) ->
         error          -> {error, Acc, Words}
     end.
 
+remove_path_if_empty(_, [{root, none}]) ->
+    ok;
+remove_path_if_empty(X, [{Node, W} | [{Parent, _} | _] = RestPath]) ->
+    case mnesia:read(rabbit_topic_trie_node,
+                     #trie_node{exchange_name = X, node_id = Node}, write) of
+        [] -> trie_remove_edge(X, Parent, Node, W),
+              remove_path_if_empty(X, RestPath);
+        _  -> ok
+    end.
+
 trie_child(X, Node, Word) ->
     case mnesia:read({rabbit_topic_trie_edge,
                       #trie_edge{exchange_name = X,
@@ -199,10 +176,30 @@ trie_bindings(X, Node) ->
                                    destination   = '$1'}},
     mnesia:select(rabbit_topic_trie_binding, [{MatchHead, [], ['$1']}]).
 
+trie_update_node_counts(X, Node, Field, Delta) ->
+    E = case mnesia:read(rabbit_topic_trie_node,
+                         #trie_node{exchange_name = X,
+                                    node_id       = Node}, write) of
+            []   -> #topic_trie_node{trie_node = #trie_node{
+                                       exchange_name = X,
+                                       node_id       = Node},
+                                     edge_count    = 0,
+                                     binding_count = 0};
+            [E0] -> E0
+        end,
+    case setelement(Field, E, element(Field, E) + Delta) of
+        #topic_trie_node{edge_count = 0, binding_count = 0} ->
+            ok = mnesia:delete_object(rabbit_topic_trie_node, E, write);
+        EN ->
+            ok = mnesia:write(rabbit_topic_trie_node, EN, write)
+    end.
+
 trie_add_edge(X, FromNode, ToNode, W) ->
+    trie_update_node_counts(X, FromNode, #topic_trie_node.edge_count, +1),
     trie_edge_op(X, FromNode, ToNode, W, fun mnesia:write/3).
 
 trie_remove_edge(X, FromNode, ToNode, W) ->
+    trie_update_node_counts(X, FromNode, #topic_trie_node.edge_count, -1),
     trie_edge_op(X, FromNode, ToNode, W, fun mnesia:delete_object/3).
 
 trie_edge_op(X, FromNode, ToNode, W, Op) ->
@@ -214,9 +211,11 @@ trie_edge_op(X, FromNode, ToNode, W, Op) ->
             write).
 
 trie_add_binding(X, Node, D) ->
+    trie_update_node_counts(X, Node, #topic_trie_node.binding_count, +1),
     trie_binding_op(X, Node, D, fun mnesia:write/3).
 
 trie_remove_binding(X, Node, D) ->
+    trie_update_node_counts(X, Node, #topic_trie_node.binding_count, -1),
     trie_binding_op(X, Node, D, fun mnesia:delete_object/3).
 
 trie_binding_op(X, Node, D, Op) ->
@@ -227,23 +226,11 @@ trie_binding_op(X, Node, D, Op) ->
                                            destination   = D}},
             write).
 
-trie_child_count(X, Node) ->
-    count(rabbit_topic_trie_edge,
-            #topic_trie_edge{trie_edge = #trie_edge{exchange_name = X,
-                                                    node_id       = Node,
-                                                    _             = '_'},
-                             _         = '_'}).
-
-trie_binding_count(X, Node) ->
-    count(rabbit_topic_trie_binding,
-            #topic_trie_binding{
-              trie_binding = #trie_binding{exchange_name = X,
-                                           node_id       = Node,
-                                           _             = '_'},
-              _            = '_'}).
-
-count(Table, Match) ->
-    length(mnesia:match_object(Table, Match, read)).
+trie_remove_all_nodes(X) ->
+    remove_all(rabbit_topic_trie_node,
+               #topic_trie_node{trie_node = #trie_node{exchange_name = X,
+                                                       _             = '_'},
+                                _         = '_'}).
 
 trie_remove_all_edges(X) ->
     remove_all(rabbit_topic_trie_edge,
@@ -262,7 +249,7 @@ remove_all(Table, Pattern) ->
                   mnesia:match_object(Table, Pattern, write)).
 
 new_node_id() ->
-    rabbit_guid:guid().
+    rabbit_guid:gen().
 
 split_topic_key(Key) ->
     split_topic_key(Key, [], []).
@@ -275,4 +262,3 @@ split_topic_key(<<$., Rest/binary>>, RevWordAcc, RevResAcc) ->
     split_topic_key(Rest, [], [lists:reverse(RevWordAcc) | RevResAcc]);
 split_topic_key(<<C:8, Rest/binary>>, RevWordAcc, RevResAcc) ->
     split_topic_key(Rest, [C | RevWordAcc], RevResAcc).
-
diff --git a/src/rabbit_file.erl b/src/rabbit_file.erl
index 5cb8e7b6..59df14f3 100644
--- a/src/rabbit_file.erl
+++ b/src/rabbit_file.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2011-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_file).
diff --git a/src/rabbit_framing.erl b/src/rabbit_framing.erl
index da1a6a49..a79188ab 100644
--- a/src/rabbit_framing.erl
+++ b/src/rabbit_framing.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 %% TODO auto-generate
diff --git a/src/rabbit_guid.erl b/src/rabbit_guid.erl
index 2d0f5014..ba0cb04f 100644
--- a/src/rabbit_guid.erl
+++ b/src/rabbit_guid.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_guid).
@@ -19,7 +19,8 @@
 -behaviour(gen_server).
 
 -export([start_link/0]).
--export([guid/0, string_guid/1, binstring_guid/1]).
+-export([filename/0]).
+-export([gen/0, gen_secure/0, string/2, binary/2]).
 
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2,
          code_change/3]).
@@ -38,9 +39,11 @@
 -type(guid() :: binary()).
 
 -spec(start_link/0 :: () -> rabbit_types:ok_pid_or_error()).
--spec(guid/0 :: () -> guid()).
--spec(string_guid/1 :: (any()) -> string()).
--spec(binstring_guid/1 :: (any()) -> binary()).
+-spec(filename/0 :: () -> string()).
+-spec(gen/0 :: () -> guid()).
+-spec(gen_secure/0 :: () -> guid()).
+-spec(string/2 :: (guid(), any()) -> string()).
+-spec(binary/2 :: (guid(), any()) -> binary()).
 
 -endif.
 
@@ -50,8 +53,14 @@ start_link() ->
     gen_server:start_link({local, ?SERVER}, ?MODULE,
                           [update_disk_serial()], []).
 
+%% We use this to detect a (possibly rather old) Mnesia directory,
+%% since it has existed since at least 1.7.0 (as far back as I cared
+%% to go).
+filename() ->
+    filename:join(rabbit_mnesia:dir(), ?SERIAL_FILENAME).
+
 update_disk_serial() ->
-    Filename = filename:join(rabbit_mnesia:dir(), ?SERIAL_FILENAME),
+    Filename = filename(),
     Serial = case rabbit_file:read_term_file(Filename) of
                  {ok, [Num]}     -> Num;
                  {error, enoent} -> 0;
@@ -65,11 +74,8 @@ update_disk_serial() ->
     end,
     Serial.
 
-%% generate a GUID.
-%%
-%% The id is only unique within a single cluster and as long as the
-%% serial store hasn't been deleted.
-guid() ->
+%% Generate an un-hashed guid.
+fresh() ->
     %% We don't use erlang:now() here because a) it may return
     %% duplicates when the system clock has been rewound prior to a
     %% restart, or ids were generated at a high rate (which causes
@@ -78,29 +84,74 @@ guid() ->
     %%
     %% A persisted serial number, the node, and a unique reference
     %% (per node incarnation) uniquely identifies a process in space
-    %% and time. We combine that with a process-local counter to give
-    %% us a GUID.
-    G = case get(guid) of
-            undefined -> Serial = gen_server:call(?SERVER, serial, infinity),
-                         {{Serial, node(), make_ref()}, 0};
+    %% and time.
+    Serial = gen_server:call(?SERVER, serial, infinity),
+    {Serial, node(), make_ref()}.
+
+advance_blocks({B1, B2, B3, B4}, I) ->
+    %% To produce a new set of blocks, we create a new 32bit block
+    %% hashing {B5, I}. The new hash is used as last block, and the
+    %% other three blocks are XORed with it.
+    %%
+    %% Doing this is convenient because it avoids cascading conflits,
+    %% while being very fast. The conflicts are avoided by propagating
+    %% the changes through all the blocks at each round by XORing, so
+    %% the only occasion in which a collision will take place is when
+    %% all 4 blocks are the same and the counter is the same.
+    %%
+    %% The range (2^32) is provided explicitly since phash uses 2^27
+    %% by default.
+    B5 = erlang:phash2({B1, I}, 4294967296),
+    {{(B2 bxor B5), (B3 bxor B5), (B4 bxor B5), B5}, I+1}.
+
+blocks_to_binary({B1, B2, B3, B4}) -> <<B1:32, B2:32, B3:32, B4:32>>.
+
+%% generate a GUID. This function should be used when performance is a
+%% priority and predictability is not an issue. Otherwise use
+%% gen_secure/0.
+gen() ->
+    %% We hash a fresh GUID with md5, split it in 4 blocks, and each
+    %% time we need a new guid we rotate them producing a new hash
+    %% with the aid of the counter. Look at the comments in
+    %% advance_blocks/2 for details.
+    {BS, I} = case get(guid) of
+                  undefined -> <<B1:32, B2:32, B3:32, B4:32>> =
+                                   erlang:md5(term_to_binary(fresh())),
+                               {{B1,B2,B3,B4}, 0};
+                  {BS0, I0} -> advance_blocks(BS0, I0)
+              end,
+    put(guid, {BS, I}),
+    blocks_to_binary(BS).
+
+%% generate a non-predictable GUID.
+%%
+%% The id is only unique within a single cluster and as long as the
+%% serial store hasn't been deleted.
+%%
+%% If you are not concerned with predictability, gen/0 is faster.
+gen_secure() ->
+    %% Here instead of hashing once we hash the GUID and the counter
+    %% each time, so that the GUID is not predictable.
+    G = case get(guid_secure) of
+            undefined -> {fresh(), 0};
             {S, I}    -> {S, I+1}
         end,
-    put(guid, G),
+    put(guid_secure, G),
     erlang:md5(term_to_binary(G)).
 
 %% generate a readable string representation of a GUID.
 %%
 %% employs base64url encoding, which is safer in more contexts than
 %% plain base64.
-string_guid(Prefix) ->
+string(G, Prefix) ->
     Prefix ++ "-" ++ lists:foldl(fun ($\+, Acc) -> [$\- | Acc];
                                      ($\/, Acc) -> [$\_ | Acc];
                                      ($\=, Acc) -> Acc;
                                      (Chr, Acc) -> [Chr | Acc]
-                                 end, [], base64:encode_to_string(guid())).
+                                 end, [], base64:encode_to_string(G)).
 
-binstring_guid(Prefix) ->
-    list_to_binary(string_guid(Prefix)).
+binary(G, Prefix) ->
+    list_to_binary(string(G, Prefix)).
 
 %%----------------------------------------------------------------------------
 
diff --git a/src/rabbit_heartbeat.erl b/src/rabbit_heartbeat.erl
index 177ae868..80b4e768 100644
--- a/src/rabbit_heartbeat.erl
+++ b/src/rabbit_heartbeat.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_heartbeat).
diff --git a/src/rabbit_limiter.erl b/src/rabbit_limiter.erl
index 8a08d4b6..2b15498e 100644
--- a/src/rabbit_limiter.erl
+++ b/src/rabbit_limiter.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_limiter).
@@ -192,7 +192,7 @@ terminate(_, _) ->
     ok.
 
 code_change(_, State, _) ->
-    State.
+    {ok, State}.
 
 %%----------------------------------------------------------------------------
 %% Internal plumbing
diff --git a/src/rabbit_log.erl b/src/rabbit_log.erl
index 558e0957..a6b4eeb0 100644
--- a/src/rabbit_log.erl
+++ b/src/rabbit_log.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_log).
@@ -23,8 +23,7 @@
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
          terminate/2, code_change/3]).
 
--export([debug/1, debug/2, message/4, info/1, info/2,
-         warning/1, warning/2, error/1, error/2]).
+-export([log/3, log/4, info/1, info/2, warning/1, warning/2, error/1, error/2]).
 
 -define(SERVER, ?MODULE).
 
@@ -32,9 +31,15 @@
 
 -ifdef(use_specs).
 
+-export_type([level/0]).
+
+-type(category() :: atom()).
+-type(level() :: 'info' | 'warning' | 'error').
+
 -spec(start_link/0 :: () -> rabbit_types:ok_pid_or_error()).
--spec(debug/1 :: (string()) -> 'ok').
--spec(debug/2 :: (string(), [any()]) -> 'ok').
+
+-spec(log/3 :: (category(), level(), string()) -> 'ok').
+-spec(log/4 :: (category(), level(), string(), [any()]) -> 'ok').
 -spec(info/1 :: (string()) -> 'ok').
 -spec(info/2 :: (string(), [any()]) -> 'ok').
 -spec(warning/1 :: (string()) -> 'ok').
@@ -42,84 +47,47 @@
 -spec(error/1 :: (string()) -> 'ok').
 -spec(error/2 :: (string(), [any()]) -> 'ok').
 
--spec(message/4 :: (_,_,_,_) -> 'ok').
-
 -endif.
 
 %%----------------------------------------------------------------------------
-
 start_link() ->
     gen_server:start_link({local, ?SERVER}, ?MODULE, [], []).
+log(Category, Level, Fmt) -> log(Category, Level, Fmt, []).
 
-debug(Fmt) ->
-    gen_server:cast(?SERVER, {debug, Fmt}).
-
-debug(Fmt, Args) when is_list(Args) ->
-    gen_server:cast(?SERVER, {debug, Fmt, Args}).
-
-message(Direction, Channel, MethodRecord, Content) ->
-    gen_server:cast(?SERVER,
-                    {message, Direction, Channel, MethodRecord, Content}).
+log(Category, Level, Fmt, Args) when is_list(Args) ->
+    gen_server:cast(?SERVER, {log, Category, Level, Fmt, Args}).
 
-info(Fmt) ->
-    gen_server:cast(?SERVER, {info, Fmt}).
-
-info(Fmt, Args) when is_list(Args) ->
-    gen_server:cast(?SERVER, {info, Fmt, Args}).
-
-warning(Fmt) ->
-    gen_server:cast(?SERVER, {warning, Fmt}).
-
-warning(Fmt, Args) when is_list(Args) ->
-    gen_server:cast(?SERVER, {warning, Fmt, Args}).
-
-error(Fmt) ->
-    gen_server:cast(?SERVER, {error, Fmt}).
-
-error(Fmt, Args) when is_list(Args) ->
-    gen_server:cast(?SERVER, {error, Fmt, Args}).
+info(Fmt)          -> log(default, info,    Fmt).
+info(Fmt, Args)    -> log(default, info,    Fmt, Args).
+warning(Fmt)       -> log(default, warning, Fmt).
+warning(Fmt, Args) -> log(default, warning, Fmt, Args).
+error(Fmt)         -> log(default, error,   Fmt).
+error(Fmt, Args)   -> log(default, error,   Fmt, Args).
 
 %%--------------------------------------------------------------------
 
-init([]) -> {ok, none}.
+init([]) ->
+    {ok, CatLevelList} = application:get_env(log_levels),
+    CatLevels = [{Cat, level(Level)} || {Cat, Level} <- CatLevelList],
+    {ok, orddict:from_list(CatLevels)}.
 
 handle_call(_Request, _From, State) ->
     {noreply, State}.
 
-handle_cast({debug, Fmt}, State) ->
-    io:format("debug:: "), io:format(Fmt),
-    error_logger:info_msg("debug:: " ++ Fmt),
-    {noreply, State};
-handle_cast({debug, Fmt, Args}, State) ->
-    io:format("debug:: "), io:format(Fmt, Args),
-    error_logger:info_msg("debug:: " ++ Fmt, Args),
-    {noreply, State};
-handle_cast({message, Direction, Channel, MethodRecord, Content}, State) ->
-    io:format("~s ch~p ~p~n",
-              [case Direction of
-                   in -> "-->";
-                   out -> "<--" end,
-               Channel,
-               {MethodRecord, Content}]),
-    {noreply, State};
-handle_cast({info, Fmt}, State) ->
-    error_logger:info_msg(Fmt),
-    {noreply, State};
-handle_cast({info, Fmt, Args}, State) ->
-    error_logger:info_msg(Fmt, Args),
-    {noreply, State};
-handle_cast({warning, Fmt}, State) ->
-    error_logger:warning_msg(Fmt),
-    {noreply, State};
-handle_cast({warning, Fmt, Args}, State) ->
-    error_logger:warning_msg(Fmt, Args),
-    {noreply, State};
-handle_cast({error, Fmt}, State) ->
-    error_logger:error_msg(Fmt),
-    {noreply, State};
-handle_cast({error, Fmt, Args}, State) ->
-    error_logger:error_msg(Fmt, Args),
-    {noreply, State};
+handle_cast({log, Category, Level, Fmt, Args}, CatLevels) ->
+    CatLevel = case orddict:find(Category, CatLevels) of
+                   {ok, L} -> L;
+                   error   -> level(info)
+               end,
+    case level(Level) =< CatLevel of
+        false -> ok;
+        true  -> (case Level of
+                      info    -> fun error_logger:info_msg/2;
+                      warning -> fun error_logger:warning_msg/2;
+                      error   -> fun error_logger:error_msg/2
+                  end)(Fmt, Args)
+    end,
+    {noreply, CatLevels};
 handle_cast(_Msg, State) ->
     {noreply, State}.
 
@@ -132,3 +100,9 @@ terminate(_Reason, _State) ->
 code_change(_OldVsn, State, _Extra) ->
     {ok, State}.
 
+%%--------------------------------------------------------------------
+
+level(info)    -> 3;
+level(warning) -> 2;
+level(error)   -> 1;
+level(none)    -> 0.
diff --git a/src/rabbit_memory_monitor.erl b/src/rabbit_memory_monitor.erl
index 02f3158f..f22ad874 100644
--- a/src/rabbit_memory_monitor.erl
+++ b/src/rabbit_memory_monitor.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 
@@ -178,11 +178,8 @@ code_change(_OldVsn, State, _Extra) ->
 %% Internal functions
 %%----------------------------------------------------------------------------
 
-zero_clamp(Sum) ->
-    case Sum < ?EPSILON of
-        true -> 0.0;
-        false -> Sum
-    end.
+zero_clamp(Sum) when Sum < ?EPSILON -> 0.0;
+zero_clamp(Sum)                     -> Sum.
 
 internal_deregister(Pid, Demonitor,
                     State = #state { queue_duration_sum = Sum,
@@ -240,26 +237,21 @@ internal_update(State = #state { queue_durations = Durations,
                   fun (Proc = #process { reported = QueueDuration,
                                          sent = PrevSendDuration,
                                          callback = {M, F, A} }, true) ->
-                          case (case {QueueDuration, PrevSendDuration} of
-                                    {infinity, infinity} ->
-                                        true;
-                                    {infinity, D} ->
-                                        DesiredDurationAvg1 < D;
-                                    {D, infinity} ->
-                                        DesiredDurationAvg1 < D;
-                                    {D1, D2} ->
-                                        DesiredDurationAvg1 <
-                                            lists:min([D1,D2])
-                                end) of
-                              true ->
-                                  ok = erlang:apply(
-                                         M, F, A ++ [DesiredDurationAvg1]),
-                                  ets:insert(
-                                    Durations,
-                                    Proc #process {sent = DesiredDurationAvg1});
-                              false ->
-                                  true
+                          case should_send(QueueDuration, PrevSendDuration,
+                                           DesiredDurationAvg1) of
+                              true  -> ok = erlang:apply(
+                                              M, F, A ++ [DesiredDurationAvg1]),
+                                       ets:insert(
+                                         Durations,
+                                         Proc #process {
+                                           sent = DesiredDurationAvg1});
+                              false -> true
                           end
                   end, true, Durations)
     end,
     State1.
+
+should_send(infinity, infinity,  _) -> true;
+should_send(infinity,        D, DD) -> DD < D;
+should_send(D,        infinity, DD) -> DD < D;
+should_send(D1,             D2, DD) -> DD < lists:min([D1, D2]).
diff --git a/src/rabbit_mirror_queue_coordinator.erl b/src/rabbit_mirror_queue_coordinator.erl
index 8ed2bede..17e2ffb4 100644
--- a/src/rabbit_mirror_queue_coordinator.erl
+++ b/src/rabbit_mirror_queue_coordinator.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2010-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2010-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_mirror_queue_coordinator).
@@ -325,11 +325,10 @@ init([#amqqueue { name = QueueName } = Q, GM, DeathFun, LengthFun]) ->
                   true = link(GM),
                   GM
           end,
-    {ok, _TRef} =
-        timer:apply_interval(?ONE_SECOND, gm, broadcast, [GM1, heartbeat]),
+    ensure_gm_heartbeat(),
     {ok, #state { q          = Q,
                   gm         = GM1,
-                  monitors   = dict:new(),
+                  monitors   = pmon:new(),
                   death_fun  = DeathFun,
                   length_fun = LengthFun },
      hibernate,
@@ -354,25 +353,21 @@ handle_cast(request_length, State = #state { length_fun = LengthFun }) ->
     ok = LengthFun(),
     noreply(State);
 
-handle_cast({ensure_monitoring, Pids},
-            State = #state { monitors = Monitors }) ->
-    Monitors1 =
-        lists:foldl(fun (Pid, MonitorsN) ->
-                            case dict:is_key(Pid, MonitorsN) of
-                                true  -> MonitorsN;
-                                false -> MRef = erlang:monitor(process, Pid),
-                                         dict:store(Pid, MRef, MonitorsN)
-                            end
-                    end, Monitors, Pids),
-    noreply(State #state { monitors = Monitors1 }).
+handle_cast({ensure_monitoring, Pids}, State = #state { monitors = Mons }) ->
+    noreply(State #state { monitors = pmon:monitor_all(Pids, Mons) }).
+
+handle_info(send_gm_heartbeat, State = #state { gm = GM }) ->
+    gm:broadcast(GM, heartbeat),
+    ensure_gm_heartbeat(),
+    noreply(State);
 
 handle_info({'DOWN', _MonitorRef, process, Pid, _Reason},
-            State = #state { monitors  = Monitors,
+            State = #state { monitors  = Mons,
                              death_fun = DeathFun }) ->
-    noreply(case dict:is_key(Pid, Monitors) of
+    noreply(case pmon:is_monitored(Pid, Mons) of
                 false -> State;
                 true  -> ok = DeathFun(Pid),
-                         State #state { monitors = dict:erase(Pid, Monitors) }
+                         State #state { monitors = pmon:erase(Pid, Mons) }
             end);
 
 handle_info(Msg, State) ->
@@ -419,3 +414,6 @@ noreply(State) ->
 
 reply(Reply, State) ->
     {reply, Reply, State, hibernate}.
+
+ensure_gm_heartbeat() ->
+    erlang:send_after(?ONE_SECOND, self(), send_gm_heartbeat).
diff --git a/src/rabbit_mirror_queue_master.erl b/src/rabbit_mirror_queue_master.erl
index f60562ef..4e71cc43 100644
--- a/src/rabbit_mirror_queue_master.erl
+++ b/src/rabbit_mirror_queue_master.erl
@@ -11,17 +11,17 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2010-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2010-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_mirror_queue_master).
 
 -export([init/3, terminate/2, delete_and_terminate/2,
          purge/1, publish/4, publish_delivered/5, fetch/2, ack/2,
-         requeue/2, len/1, is_empty/1, drain_confirmed/1, dropwhile/2,
+         requeue/2, len/1, is_empty/1, drain_confirmed/1, dropwhile/3,
          set_ram_duration_target/2, ram_duration/1,
          needs_timeout/1, timeout/1, handle_pre_hibernate/1,
-         status/1, invoke/3, is_duplicate/2, discard/3]).
+         status/1, invoke/3, is_duplicate/2, discard/3, fold/3]).
 
 -export([start/1, stop/0]).
 
@@ -59,10 +59,6 @@
                                  known_senders       :: set()
                                }).
 
--type(ack()   :: non_neg_integer()).
--type(state() :: master_state()).
--include("rabbit_backing_queue_spec.hrl").
-
 -spec(promote_backing_queue_state/6 ::
         (pid(), atom(), any(), pid(), dict(), [pid()]) -> master_state()).
 -spec(sender_death_fun/0 :: () -> death_fun()).
@@ -138,7 +134,7 @@ delete_and_terminate(Reason, State = #state { gm                  = GM,
 purge(State = #state { gm                  = GM,
                        backing_queue       = BQ,
                        backing_queue_state = BQS }) ->
-    ok = gm:broadcast(GM, {set_length, 0}),
+    ok = gm:broadcast(GM, {set_length, 0, false}),
     {Count, BQS1} = BQ:purge(BQS),
     {Count, State #state { backing_queue_state = BQS1,
                            set_delivered       = 0 }}.
@@ -172,17 +168,19 @@ publish_delivered(AckRequired, Msg = #basic_message { id = MsgId }, MsgProps,
      ensure_monitoring(ChPid, State #state { backing_queue_state = BQS1,
                                              ack_msg_id          = AM1 })}.
 
-dropwhile(Fun, State = #state { gm                  = GM,
-                                backing_queue       = BQ,
-                                backing_queue_state = BQS,
-                                set_delivered       = SetDelivered }) ->
-    Len = BQ:len(BQS),
-    BQS1 = BQ:dropwhile(Fun, BQS),
-    Dropped = Len - BQ:len(BQS1),
+dropwhile(Pred, AckRequired,
+          State = #state{gm                  = GM,
+                         backing_queue       = BQ,
+                         set_delivered       = SetDelivered,
+                         backing_queue_state = BQS }) ->
+    Len  = BQ:len(BQS),
+    {Msgs, BQS1} = BQ:dropwhile(Pred, AckRequired, BQS),
+    Len1 = BQ:len(BQS1),
+    ok = gm:broadcast(GM, {set_length, Len1, AckRequired}),
+    Dropped = Len - Len1,
     SetDelivered1 = lists:max([0, SetDelivered - Dropped]),
-    ok = gm:broadcast(GM, {set_length, BQ:len(BQS1)}),
-    State #state { backing_queue_state = BQS1,
-                   set_delivered       = SetDelivered1 }.
+    {Msgs, State #state { backing_queue_state = BQS1,
+                          set_delivered       = SetDelivered1 } }.
 
 drain_confirmed(State = #state { backing_queue       = BQ,
                                  backing_queue_state = BQS,
@@ -240,14 +238,18 @@ ack(AckTags, State = #state { gm                  = GM,
                               backing_queue_state = BQS,
                               ack_msg_id          = AM }) ->
     {MsgIds, BQS1} = BQ:ack(AckTags, BQS),
-    AM1 = lists:foldl(fun dict:erase/2, AM, AckTags),
     case MsgIds of
         [] -> ok;
         _  -> ok = gm:broadcast(GM, {ack, MsgIds})
     end,
+    AM1 = lists:foldl(fun dict:erase/2, AM, AckTags),
     {MsgIds, State #state { backing_queue_state = BQS1,
                             ack_msg_id          = AM1 }}.
 
+fold(MsgFun, State = #state { backing_queue       = BQ,
+                              backing_queue_state = BQS }, AckTags) ->
+    State #state { backing_queue_state = BQ:fold(MsgFun, BQS, AckTags) }.
+
 requeue(AckTags, State = #state { gm                  = GM,
                                   backing_queue       = BQ,
                                   backing_queue_state = BQS }) ->
@@ -280,8 +282,10 @@ handle_pre_hibernate(State = #state { backing_queue       = BQ,
                                       backing_queue_state = BQS }) ->
     State #state { backing_queue_state = BQ:handle_pre_hibernate(BQS) }.
 
-status(#state { backing_queue = BQ, backing_queue_state = BQS }) ->
-    BQ:status(BQS).
+status(State = #state { backing_queue = BQ, backing_queue_state = BQS }) ->
+    BQ:status(BQS) ++
+        [ {mirror_seen,    dict:size(State #state.seen_status)},
+          {mirror_senders, sets:size(State #state.known_senders)} ].
 
 invoke(?MODULE, Fun, State) ->
     Fun(?MODULE, State);
diff --git a/src/rabbit_mirror_queue_misc.erl b/src/rabbit_mirror_queue_misc.erl
index baebc52b..180677fe 100644
--- a/src/rabbit_mirror_queue_misc.erl
+++ b/src/rabbit_mirror_queue_misc.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2010-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2010-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_mirror_queue_misc).
@@ -134,14 +134,17 @@ add_mirror(Queue, MirrorNode) ->
       Queue,
       fun (#amqqueue { name = Name, pid = QPid, slave_pids = SPids } = Q) ->
               case [Pid || Pid <- [QPid | SPids], node(Pid) =:= MirrorNode] of
-                  []  -> Result = rabbit_mirror_queue_slave_sup:start_child(
-                                    MirrorNode, [Q]),
-                         rabbit_log:info(
-                           "Adding mirror of queue ~s on node ~p: ~p~n",
-                           [rabbit_misc:rs(Name), MirrorNode, Result]),
-                         case Result of
-                             {ok, _Pid} -> ok;
-                             _          -> Result
+                  []  -> case rabbit_mirror_queue_slave_sup:start_child(
+                                MirrorNode, [Q]) of
+                             {ok, undefined} -> %% Already running
+                                 ok;
+                             {ok, SPid} ->
+                                 rabbit_log:info(
+                                   "Adding mirror of ~s on node ~p: ~p~n",
+                                   [rabbit_misc:rs(Name), MirrorNode, SPid]),
+                                 ok;
+                             Other ->
+                                 Other
                          end;
                   [_] -> {error, {queue_already_mirrored_on_node, MirrorNode}}
               end
diff --git a/src/rabbit_mirror_queue_slave.erl b/src/rabbit_mirror_queue_slave.erl
index d68063db..e412fbbc 100644
--- a/src/rabbit_mirror_queue_slave.erl
+++ b/src/rabbit_mirror_queue_slave.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2010-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2010-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_mirror_queue_slave).
@@ -90,7 +90,7 @@
                }).
 
 start_link(Q) ->
-    gen_server2:start_link(?MODULE, [Q], []).
+    gen_server2:start_link(?MODULE, Q, []).
 
 set_maximum_since_use(QPid, Age) ->
     gen_server2:cast(QPid, {set_maximum_since_use, Age}).
@@ -98,59 +98,64 @@ set_maximum_since_use(QPid, Age) ->
 info(QPid) ->
     gen_server2:call(QPid, info, infinity).
 
-init([#amqqueue { name = QueueName } = Q]) ->
-    process_flag(trap_exit, true), %% amqqueue_process traps exits too.
-    {ok, GM} = gm:start_link(QueueName, ?MODULE, [self()]),
-    receive {joined, GM} ->
-            ok
-    end,
+init(#amqqueue { name = QueueName } = Q) ->
     Self = self(),
     Node = node(),
-    {ok, MPid} =
-        rabbit_misc:execute_mnesia_transaction(
-          fun () ->
-                  [Q1 = #amqqueue { pid = QPid, slave_pids = MPids }] =
-                      mnesia:read({rabbit_queue, QueueName}),
-                  %% ASSERTION
-                  [] = [Pid || Pid <- [QPid | MPids], node(Pid) =:= Node],
-                  MPids1 = MPids ++ [Self],
-                  ok = rabbit_amqqueue:store_queue(
-                         Q1 #amqqueue { slave_pids = MPids1 }),
-                  {ok, QPid}
-          end),
-    erlang:monitor(process, MPid),
-    ok = file_handle_cache:register_callback(
-           rabbit_amqqueue, set_maximum_since_use, [Self]),
-    ok = rabbit_memory_monitor:register(
-           Self, {rabbit_amqqueue, set_ram_duration_target, [Self]}),
-    {ok, BQ} = application:get_env(backing_queue_module),
-    BQS = bq_init(BQ, Q, false),
-    State = #state { q                   = Q,
-                     gm                  = GM,
-                     master_pid          = MPid,
-                     backing_queue       = BQ,
-                     backing_queue_state = BQS,
-                     rate_timer_ref      = undefined,
-                     sync_timer_ref      = undefined,
-
-                     sender_queues       = dict:new(),
-                     msg_id_ack          = dict:new(),
-                     ack_num             = 0,
-
-                     msg_id_status       = dict:new(),
-                     known_senders       = dict:new(),
-
-                     synchronised        = false
+    case rabbit_misc:execute_mnesia_transaction(
+           fun () ->
+                   [Q1 = #amqqueue { pid = QPid, slave_pids = MPids }] =
+                       mnesia:read({rabbit_queue, QueueName}),
+                   case [Pid || Pid <- [QPid | MPids], node(Pid) =:= Node] of
+                       []     -> MPids1 = MPids ++ [Self],
+                                 ok = rabbit_amqqueue:store_queue(
+                                        Q1 #amqqueue { slave_pids = MPids1 }),
+                                 {new, QPid};
+                       [SPid] -> true = rabbit_misc:is_process_alive(SPid),
+                                 existing
+                   end
+           end) of
+        {new, MPid} ->
+            process_flag(trap_exit, true), %% amqqueue_process traps exits too.
+            {ok, GM} = gm:start_link(QueueName, ?MODULE, [self()]),
+            receive {joined, GM} ->
+                    ok
+            end,
+            erlang:monitor(process, MPid),
+            ok = file_handle_cache:register_callback(
+                   rabbit_amqqueue, set_maximum_since_use, [Self]),
+            ok = rabbit_memory_monitor:register(
+                   Self, {rabbit_amqqueue, set_ram_duration_target, [Self]}),
+            {ok, BQ} = application:get_env(backing_queue_module),
+            BQS = bq_init(BQ, Q, false),
+            State = #state { q                   = Q,
+                             gm                  = GM,
+                             master_pid          = MPid,
+                             backing_queue       = BQ,
+                             backing_queue_state = BQS,
+                             rate_timer_ref      = undefined,
+                             sync_timer_ref      = undefined,
+
+                             sender_queues       = dict:new(),
+                             msg_id_ack          = dict:new(),
+                             ack_num             = 0,
+
+                             msg_id_status       = dict:new(),
+                             known_senders       = pmon:new(),
+
+                             synchronised        = false
                    },
-    rabbit_event:notify(queue_slave_created,
-                        infos(?CREATION_EVENT_KEYS, State)),
-    ok = gm:broadcast(GM, request_length),
-    {ok, State, hibernate,
-     {backoff, ?HIBERNATE_AFTER_MIN, ?HIBERNATE_AFTER_MIN, ?DESIRED_HIBERNATE}}.
-
-handle_call({deliver_immediately, Delivery = #delivery {}}, From, State) ->
-    %% Synchronous, "immediate" delivery mode
+            rabbit_event:notify(queue_slave_created,
+                                infos(?CREATION_EVENT_KEYS, State)),
+            ok = gm:broadcast(GM, request_length),
+            {ok, State, hibernate,
+             {backoff, ?HIBERNATE_AFTER_MIN, ?HIBERNATE_AFTER_MIN,
+              ?DESIRED_HIBERNATE}};
+        existing ->
+            ignore
+    end.
 
+handle_call({deliver, Delivery = #delivery { immediate = true }},
+            From, State) ->
     %% It is safe to reply 'false' here even if a) we've not seen the
     %% msg via gm, or b) the master dies before we receive the msg via
     %% gm. In the case of (a), we will eventually receive the msg via
@@ -166,8 +171,8 @@ handle_call({deliver_immediately, Delivery = #delivery {}}, From, State) ->
     gen_server2:reply(From, false), %% master may deliver it, not us
     noreply(maybe_enqueue_message(Delivery, false, State));
 
-handle_call({deliver, Delivery = #delivery {}}, From, State) ->
-    %% Synchronous, "mandatory" delivery mode
+handle_call({deliver, Delivery = #delivery { mandatory = true }},
+            From, State) ->
     gen_server2:reply(From, true), %% amqqueue throws away the result anyway
     noreply(maybe_enqueue_message(Delivery, true, State));
 
@@ -208,8 +213,12 @@ handle_cast({run_backing_queue, Mod, Fun}, State) ->
 handle_cast({gm, Instruction}, State) ->
     handle_process_result(process_instruction(Instruction, State));
 
-handle_cast({deliver, Delivery = #delivery {}}, State) ->
+handle_cast({deliver, Delivery = #delivery{sender = Sender}, Flow}, State) ->
     %% Asynchronous, non-"mandatory", non-"immediate" deliver mode.
+    case Flow of
+        flow   -> credit_flow:ack(Sender);
+        noflow -> ok
+    end,
     noreply(maybe_enqueue_message(Delivery, true, State));
 
 handle_cast({set_maximum_since_use, Age}, State) ->
@@ -250,6 +259,10 @@ handle_info({'DOWN', _MonitorRef, process, ChPid, _Reason}, State) ->
 handle_info({'EXIT', _Pid, Reason}, State) ->
     {stop, Reason, State};
 
+handle_info({bump_credit, Msg}, State) ->
+    credit_flow:handle_bump_msg(Msg),
+    noreply(State);
+
 handle_info(Msg, State) ->
     {stop, {unexpected_info, Msg}, State}.
 
@@ -273,7 +286,7 @@ terminate(Reason, #state { q                   = Q,
                            rate_timer_ref      = RateTRef }) ->
     ok = gm:leave(GM),
     QueueState = rabbit_amqqueue_process:init_with_backing_queue_state(
-                   Q, BQ, BQS, RateTRef, [], [], dict:new()),
+                   Q, BQ, BQS, RateTRef, [], [], pmon:new(), dict:new()),
     rabbit_amqqueue_process:terminate(Reason, QueueState);
 terminate([_SPid], _Reason) ->
     %% gm case
@@ -417,7 +430,7 @@ confirm_messages(MsgIds, State = #state { msg_id_status = MS }) ->
                           Acc
                   end
           end, {gb_trees:empty(), MS}, MsgIds),
-    rabbit_misc:gb_trees_foreach(fun rabbit_channel:confirm/2, CMs),
+    rabbit_misc:gb_trees_foreach(fun rabbit_misc:confirm_to_sender/2, CMs),
     State #state { msg_id_status = MS1 }.
 
 handle_process_result({ok,   State}) -> noreply(State);
@@ -446,12 +459,8 @@ promote_me(From, #state { q                   = Q = #amqqueue { name = QName },
 
     %% Everything that we're monitoring, we need to ensure our new
     %% coordinator is monitoring.
-
-    MonitoringPids = [begin true = erlang:demonitor(MRef),
-                            Pid
-                      end || {Pid, MRef} <- dict:to_list(KS)],
-    ok = rabbit_mirror_queue_coordinator:ensure_monitoring(
-           CPid, MonitoringPids),
+    MPids = pmon:monitored(KS),
+    ok = rabbit_mirror_queue_coordinator:ensure_monitoring(CPid, MPids),
 
     %% We find all the messages that we've received from channels but
     %% not from gm, and if they're due to be enqueued on promotion
@@ -524,7 +533,7 @@ promote_me(From, #state { q                   = Q = #amqqueue { name = QName },
                    Status =:= published orelse Status =:= confirmed]),
 
     MasterState = rabbit_mirror_queue_master:promote_backing_queue_state(
-                    CPid, BQ, BQS, GM, SS, MonitoringPids),
+                    CPid, BQ, BQS, GM, SS, MPids),
 
     MTC = lists:foldl(fun ({MsgId, {published, ChPid, MsgSeqNo}}, MTC0) ->
                               gb_trees:insert(MsgId, {ChPid, MsgSeqNo}, MTC0);
@@ -537,7 +546,7 @@ promote_me(From, #state { q                   = Q = #amqqueue { name = QName },
                               {Delivery, true} <- queue:to_list(PubQ)],
     QueueState = rabbit_amqqueue_process:init_with_backing_queue_state(
                    Q1, rabbit_mirror_queue_master, MasterState, RateTRef,
-                   AckTags, Deliveries, MTC),
+                   AckTags, Deliveries, KS, MTC),
     {become, rabbit_amqqueue_process, QueueState, hibernate}.
 
 noreply(State) ->
@@ -592,16 +601,13 @@ stop_rate_timer(State = #state { rate_timer_ref = TRef }) ->
     State #state { rate_timer_ref = undefined }.
 
 ensure_monitoring(ChPid, State = #state { known_senders = KS }) ->
-    case dict:is_key(ChPid, KS) of
-        true  -> State;
-        false -> MRef = erlang:monitor(process, ChPid),
-                 State #state { known_senders = dict:store(ChPid, MRef, KS) }
-    end.
+    State #state { known_senders = pmon:monitor(ChPid, KS) }.
 
 local_sender_death(ChPid, State = #state { known_senders = KS }) ->
-    ok = case dict:is_key(ChPid, KS) of
+    ok = case pmon:is_monitored(ChPid, KS) of
              false -> ok;
-             true  -> confirm_sender_death(ChPid)
+             true  -> credit_flow:peer_down(ChPid),
+                      confirm_sender_death(ChPid)
          end,
     State.
 
@@ -614,7 +620,7 @@ confirm_sender_death(Pid) ->
         fun (?MODULE, State = #state { known_senders = KS,
                                        gm            = GM }) ->
                 %% We're running still as a slave
-                ok = case dict:is_key(Pid, KS) of
+                ok = case pmon:is_monitored(Pid, KS) of
                          false -> ok;
                          true  -> gm:broadcast(GM, {ensure_monitoring, [Pid]}),
                                   confirm_sender_death(Pid)
@@ -651,7 +657,7 @@ maybe_enqueue_message(
         {ok, {confirmed, ChPid}} ->
             %% BQ has confirmed it but we didn't know what the
             %% msg_seq_no was at the time. We do now!
-            ok = rabbit_channel:confirm(ChPid, [MsgSeqNo]),
+            ok = rabbit_misc:confirm_to_sender(ChPid, [MsgSeqNo]),
             SQ1 = remove_from_pending_ch(MsgId, ChPid, SQ),
             State1 #state { sender_queues = SQ1,
                             msg_id_status = dict:erase(MsgId, MS) };
@@ -668,7 +674,7 @@ maybe_enqueue_message(
                       msg_id_status =
                           dict:store(MsgId, {published, ChPid, MsgSeqNo}, MS) };
                 immediately ->
-                    ok = rabbit_channel:confirm(ChPid, [MsgSeqNo]),
+                    ok = rabbit_misc:confirm_to_sender(ChPid, [MsgSeqNo]),
                     SQ1 = remove_from_pending_ch(MsgId, ChPid, SQ),
                     State1 #state { msg_id_status = dict:erase(MsgId, MS),
                                     sender_queues = SQ1 }
@@ -730,7 +736,7 @@ process_instruction(
                         {MQ2, PendingCh,
                          dict:store(MsgId, {published, ChPid, MsgSeqNo}, MS)};
                     immediately ->
-                        ok = rabbit_channel:confirm(ChPid, [MsgSeqNo]),
+                        ok = rabbit_misc:confirm_to_sender(ChPid, [MsgSeqNo]),
                         {MQ2, PendingCh, MS}
                 end;
             {{value, {#delivery {}, _EnqueueOnPromotion}}, _MQ2} ->
@@ -787,23 +793,27 @@ process_instruction({discard, ChPid, Msg = #basic_message { id = MsgId }},
     {ok, State1 #state { sender_queues       = SQ1,
                          msg_id_status       = MS1,
                          backing_queue_state = BQS1 }};
-process_instruction({set_length, Length},
+process_instruction({set_length, Length, AckRequired},
                     State = #state { backing_queue       = BQ,
                                      backing_queue_state = BQS }) ->
     QLen = BQ:len(BQS),
     ToDrop = QLen - Length,
-    {ok, case ToDrop >= 0 of
-             true  -> BQS1 =
-                          lists:foldl(
-                            fun (const, BQSN) ->
-                                    {{_Msg, _IsDelivered, _AckTag, _Remaining},
-                                     BQSN1} = BQ:fetch(false, BQSN),
-                                    BQSN1
-                            end, BQS, lists:duplicate(ToDrop, const)),
-                      set_synchronised(
-                        true, State #state { backing_queue_state = BQS1 });
-             false -> State
-         end};
+    {ok,
+     case ToDrop >= 0 of
+         true ->
+             State1 =
+                 lists:foldl(
+                   fun (const, StateN = #state {backing_queue_state = BQSN}) ->
+                           {{#basic_message{id = MsgId}, _IsDelivered, AckTag,
+                             _Remaining}, BQSN1} = BQ:fetch(AckRequired, BQSN),
+                           maybe_store_ack(
+                             AckRequired, MsgId, AckTag,
+                             StateN #state { backing_queue_state = BQSN1 })
+                   end, State, lists:duplicate(ToDrop, const)),
+             set_synchronised(true, State1);
+         false ->
+             State
+     end};
 process_instruction({fetch, AckRequired, MsgId, Remaining},
                     State = #state { backing_queue       = BQ,
                                      backing_queue_state = BQS }) ->
@@ -852,21 +862,18 @@ process_instruction({sender_death, ChPid},
                     State = #state { sender_queues = SQ,
                                      msg_id_status = MS,
                                      known_senders = KS }) ->
-    {ok, case dict:find(ChPid, KS) of
-             error ->
-                 State;
-             {ok, MRef} ->
-                 true = erlang:demonitor(MRef),
-                 MS1 = case dict:find(ChPid, SQ) of
-                           error ->
-                               MS;
-                           {ok, {_MQ, PendingCh}} ->
-                               lists:foldl(fun dict:erase/2, MS,
-                                           sets:to_list(PendingCh))
-                       end,
-                 State #state { sender_queues = dict:erase(ChPid, SQ),
-                                msg_id_status = MS1,
-                                known_senders = dict:erase(ChPid, KS) }
+    {ok, case pmon:is_monitored(ChPid, KS) of
+             false -> State;
+             true  -> MS1 = case dict:find(ChPid, SQ) of
+                                error ->
+                                    MS;
+                                {ok, {_MQ, PendingCh}} ->
+                                    lists:foldl(fun dict:erase/2, MS,
+                                                sets:to_list(PendingCh))
+                            end,
+                      State #state { sender_queues = dict:erase(ChPid, SQ),
+                                     msg_id_status = MS1,
+                                     known_senders = pmon:demonitor(ChPid, KS) }
          end};
 process_instruction({length, Length},
                     State = #state { backing_queue = BQ,
diff --git a/src/rabbit_mirror_queue_slave_sup.erl b/src/rabbit_mirror_queue_slave_sup.erl
index fc04ec79..a2034876 100644
--- a/src/rabbit_mirror_queue_slave_sup.erl
+++ b/src/rabbit_mirror_queue_slave_sup.erl
@@ -11,14 +11,14 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2010-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2010-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_mirror_queue_slave_sup).
 
 -behaviour(supervisor2).
 
--export([start/0, start_link/0, start_child/2]).
+-export([start_link/0, start_child/2]).
 
 -export([init/1]).
 
@@ -26,20 +26,9 @@
 
 -define(SERVER, ?MODULE).
 
-start() ->
-    {ok, _} =
-        supervisor2:start_child(
-          rabbit_sup,
-          {rabbit_mirror_queue_slave_sup,
-           {rabbit_mirror_queue_slave_sup, start_link, []},
-           transient, infinity, supervisor, [rabbit_mirror_queue_slave_sup]}),
-    ok.
+start_link() -> supervisor2:start_link({local, ?SERVER}, ?MODULE, []).
 
-start_link() ->
-    supervisor2:start_link({local, ?SERVER}, ?MODULE, []).
-
-start_child(Node, Args) ->
-    supervisor2:start_child({?SERVER, Node}, Args).
+start_child(Node, Args) -> supervisor2:start_child({?SERVER, Node}, Args).
 
 init([]) ->
     {ok, {{simple_one_for_one_terminate, 10, 10},
diff --git a/src/rabbit_misc.erl b/src/rabbit_misc.erl
index 0578cf7d..93c784ec 100644
--- a/src/rabbit_misc.erl
+++ b/src/rabbit_misc.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_misc).
@@ -28,17 +28,20 @@
 -export([enable_cover/0, report_cover/0]).
 -export([enable_cover/1, report_cover/1]).
 -export([start_cover/1]).
+-export([confirm_to_sender/2]).
 -export([throw_on_error/2, with_exit_handler/2, filter_exit_map/2]).
+-export([is_abnormal_termination/1]).
 -export([with_user/2, with_user_and_vhost/3]).
 -export([execute_mnesia_transaction/1]).
 -export([execute_mnesia_transaction/2]).
 -export([execute_mnesia_tx_with_tail/1]).
 -export([ensure_ok/2]).
--export([makenode/1, nodeparts/1, cookie_hash/0, tcp_name/3]).
+-export([tcp_name/3]).
 -export([upmap/2, map_in_order/2]).
 -export([table_filter/3]).
 -export([dirty_read_all/1, dirty_foreach_key/2, dirty_dump_log/1]).
--export([format_stderr/2, with_local_io/1, local_info_msg/2]).
+-export([format/2, format_many/1, format_stderr/2]).
+-export([with_local_io/1, local_info_msg/2]).
 -export([start_applications/1, stop_applications/1]).
 -export([unfold/2, ceil/1, queue_fold/3]).
 -export([sort_field_table/1]).
@@ -46,16 +49,19 @@
 -export([version_compare/2, version_compare/3]).
 -export([dict_cons/3, orddict_cons/3, gb_trees_cons/3]).
 -export([gb_trees_fold/3, gb_trees_foreach/2]).
--export([get_options/2]).
+-export([parse_arguments/3]).
 -export([all_module_attributes/1, build_acyclic_graph/3]).
 -export([now_ms/0]).
 -export([const_ok/0, const/1]).
 -export([ntoa/1, ntoab/1]).
 -export([is_process_alive/1]).
--export([pget/2, pget/3, pget_or_die/2]).
+-export([pget/2, pget/3, pget_or_die/2, pset/3]).
 -export([format_message_queue/2]).
 -export([append_rpc_all_nodes/4]).
+-export([multi_call/2]).
 -export([quit/1]).
+-export([os_cmd/1]).
+-export([gb_sets_difference/2]).
 
 %%----------------------------------------------------------------------------
 
@@ -66,7 +72,7 @@
 -type(ok_or_error() :: rabbit_types:ok_or_error(any())).
 -type(thunk(T) :: fun(() -> T)).
 -type(resource_name() :: binary()).
--type(optdef() :: {flag, string()} | {option, string(), any()}).
+-type(optdef() :: flag | {option, string()}).
 -type(channel_or_connection_exit()
       :: rabbit_types:channel_exit() | rabbit_types:connection_exit()).
 -type(digraph_label() :: term()).
@@ -108,7 +114,6 @@
         (rabbit_framing:amqp_table(), binary(),
          rabbit_framing:amqp_field_type(), rabbit_framing:amqp_value())
         -> rabbit_framing:amqp_table()).
-
 -spec(r/2 :: (rabbit_types:vhost(), K)
              -> rabbit_types:r3(rabbit_types:vhost(), K, '_')
                     when is_subtype(K, atom())).
@@ -131,6 +136,7 @@
         (atom(), thunk(rabbit_types:error(any()) | {ok, A} | A)) -> A).
 -spec(with_exit_handler/2 :: (thunk(A), thunk(A)) -> A).
 -spec(filter_exit_map/2 :: (fun ((A) -> B), [A]) -> [B]).
+-spec(is_abnormal_termination/1 :: (any()) -> boolean()).
 -spec(with_user/2 :: (rabbit_types:username(), thunk(A)) -> A).
 -spec(with_user_and_vhost/3 ::
         (rabbit_types:username(), rabbit_types:vhost(), thunk(A))
@@ -141,9 +147,6 @@
 -spec(execute_mnesia_tx_with_tail/1 ::
         (thunk(fun ((boolean()) -> B))) -> B | (fun ((boolean()) -> B))).
 -spec(ensure_ok/2 :: (ok_or_error(), atom()) -> 'ok').
--spec(makenode/1 :: ({string(), string()} | string()) -> node()).
--spec(nodeparts/1 :: (node() | string()) -> {string(), string()}).
--spec(cookie_hash/0 :: () -> string()).
 -spec(tcp_name/3 ::
         (atom(), inet:ip_address(), rabbit_networking:ip_port())
         -> atom()).
@@ -155,6 +158,8 @@
 -spec(dirty_foreach_key/2 :: (fun ((any()) -> any()), atom())
                              -> 'ok' | 'aborted').
 -spec(dirty_dump_log/1 :: (file:filename()) -> ok_or_error()).
+-spec(format/2 :: (string(), [any()]) -> string()).
+-spec(format_many/1 :: ([{string(), [any()]}]) -> string()).
 -spec(format_stderr/2 :: (string(), [any()]) -> 'ok').
 -spec(with_local_io/1 :: (fun (() -> A)) -> A).
 -spec(local_info_msg/2 :: (string(), [any()]) -> 'ok').
@@ -177,8 +182,12 @@
 -spec(gb_trees_fold/3 :: (fun ((any(), any(), A) -> A), A, gb_tree()) -> A).
 -spec(gb_trees_foreach/2 ::
         (fun ((any(), any()) -> any()), gb_tree()) -> 'ok').
--spec(get_options/2 :: ([optdef()], [string()])
-                       -> {[string()], [{string(), any()}]}).
+-spec(parse_arguments/3 ::
+        ([{atom(), [{string(), optdef()}]} | atom()],
+         [{string(), optdef()}],
+         [string()])
+        -> {'ok', {atom(), [{string(), string()}], [string()]}} |
+           'no_command').
 -spec(all_module_attributes/1 :: (atom()) -> [{atom(), [term()]}]).
 -spec(build_acyclic_graph/3 ::
         (graph_vertex_fun(), graph_edge_fun(), [{atom(), [term()]}])
@@ -196,9 +205,14 @@
 -spec(pget/2 :: (term(), [term()]) -> term()).
 -spec(pget/3 :: (term(), [term()], term()) -> term()).
 -spec(pget_or_die/2 :: (term(), [term()]) -> term() | no_return()).
+-spec(pset/3 :: (term(), term(), [term()]) -> term()).
 -spec(format_message_queue/2 :: (any(), priority_queue:q()) -> term()).
 -spec(append_rpc_all_nodes/4 :: ([node()], atom(), atom(), [any()]) -> [any()]).
+-spec(multi_call/2 ::
+        ([pid()], any()) -> {[{pid(), any()}], [{pid(), any()}]}).
 -spec(quit/1 :: (integer() | string()) -> no_return()).
+-spec(os_cmd/1 :: (string()) -> string()).
+-spec(gb_sets_difference/2 :: (gb_set(), gb_set()) -> gb_set()).
 
 -endif.
 
@@ -222,7 +236,7 @@ frame_error(MethodName, BinaryFields) ->
     protocol_error(frame_error, "cannot decode ~w", [BinaryFields], MethodName).
 
 amqp_error(Name, ExplanationFormat, Params, Method) ->
-    Explanation = lists:flatten(io_lib:format(ExplanationFormat, Params)),
+    Explanation = format(ExplanationFormat, Params),
     #amqp_error{name = Name, explanation = Explanation, method = Method}.
 
 protocol_error(Name, ExplanationFormat, Params) ->
@@ -276,8 +290,7 @@ val({Type, Value}) ->
                  true  -> "~s";
                  false -> "~w"
              end,
-    lists:flatten(io_lib:format("the value '" ++ ValFmt ++ "' of type '~s'",
-                                [Value, Type])).
+    format("the value '" ++ ValFmt ++ "' of type '~s'", [Value, Type]).
 
 %% Normally we'd call mnesia:dirty_read/1 here, but that is quite
 %% expensive due to general mnesia overheads (figuring out table types
@@ -320,8 +333,7 @@ r_arg(VHostPath, Kind, Table, Key) ->
     end.
 
 rs(#resource{virtual_host = VHostPath, kind = Kind, name = Name}) ->
-    lists:flatten(io_lib:format("~s '~s' in vhost '~s'",
-                                [Kind, Name, VHostPath])).
+    format("~s '~s' in vhost '~s'", [Kind, Name, VHostPath]).
 
 enable_cover() -> enable_cover(["."]).
 
@@ -337,7 +349,7 @@ enable_cover(Dirs) ->
                 end, ok, Dirs).
 
 start_cover(NodesS) ->
-    {ok, _} = cover:start([makenode(N) || N <- NodesS]),
+    {ok, _} = cover:start([rabbit_nodes:make(N) || N <- NodesS]),
     ok.
 
 report_cover() -> report_cover(["."]).
@@ -376,6 +388,9 @@ report_coverage_percentage(File, Cov, NotCov, Mod) ->
                end,
                Mod]).
 
+confirm_to_sender(Pid, MsgSeqNos) ->
+    gen_server2:cast(Pid, {confirm, MsgSeqNos, self()}).
+
 throw_on_error(E, Thunk) ->
     case Thunk() of
         {error, Reason} -> throw({E, Reason});
@@ -401,6 +416,12 @@ filter_exit_map(F, L) ->
                     fun () -> Ref end,
                     fun () -> F(I) end) || I <- L]).
 
+is_abnormal_termination(Reason)
+  when Reason =:= noproc; Reason =:= noconnection;
+       Reason =:= normal; Reason =:= shutdown -> false;
+is_abnormal_termination({shutdown, _})        -> false;
+is_abnormal_termination(_)                    -> true.
+
 with_user(Username, Thunk) ->
     fun () ->
             case mnesia:read({rabbit_user, Username}) of
@@ -418,12 +439,25 @@ execute_mnesia_transaction(TxFun) ->
     %% Making this a sync_transaction allows us to use dirty_read
     %% elsewhere and get a consistent result even when that read
     %% executes on a different node.
-    case worker_pool:submit({mnesia, sync_transaction, [TxFun]}) of
-        {atomic,  Result} -> Result;
-        {aborted, Reason} -> throw({error, Reason})
+    case worker_pool:submit(
+           fun () ->
+                   case mnesia:is_transaction() of
+                       false -> DiskLogBefore = mnesia_dumper:get_log_writes(),
+                                Res = mnesia:sync_transaction(TxFun),
+                                DiskLogAfter  = mnesia_dumper:get_log_writes(),
+                                case DiskLogAfter == DiskLogBefore of
+                                    true  -> Res;
+                                    false -> {sync, Res}
+                                end;
+                       true  -> mnesia:sync_transaction(TxFun)
+                   end
+           end) of
+        {sync, {atomic,  Result}} -> mnesia_sync:sync(), Result;
+        {sync, {aborted, Reason}} -> throw({error, Reason});
+        {atomic,  Result}         -> Result;
+        {aborted, Reason}         -> throw({error, Reason})
     end.
 
-
 %% Like execute_mnesia_transaction/1 with additional Pre- and Post-
 %% commit function
 execute_mnesia_transaction(TxFun, PrePostCommitFun) ->
@@ -450,29 +484,10 @@ execute_mnesia_tx_with_tail(TxFun) ->
 ensure_ok(ok, _) -> ok;
 ensure_ok({error, Reason}, ErrorTag) -> throw({error, {ErrorTag, Reason}}).
 
-makenode({Prefix, Suffix}) ->
-    list_to_atom(lists:append([Prefix, "@", Suffix]));
-makenode(NodeStr) ->
-    makenode(nodeparts(NodeStr)).
-
-nodeparts(Node) when is_atom(Node) ->
-    nodeparts(atom_to_list(Node));
-nodeparts(NodeStr) ->
-    case lists:splitwith(fun (E) -> E =/= $@ end, NodeStr) of
-        {Prefix, []}     -> {_, Suffix} = nodeparts(node()),
-                            {Prefix, Suffix};
-        {Prefix, Suffix} -> {Prefix, tl(Suffix)}
-    end.
-
-cookie_hash() ->
-    base64:encode_to_string(erlang:md5(atom_to_list(erlang:get_cookie()))).
-
 tcp_name(Prefix, IPAddress, Port)
   when is_atom(Prefix) andalso is_number(Port) ->
     list_to_atom(
-      lists:flatten(
-        io_lib:format("~w_~s:~w",
-                      [Prefix, inet_parse:ntoa(IPAddress), Port]))).
+      format("~w_~s:~w", [Prefix, inet_parse:ntoa(IPAddress), Port])).
 
 %% This is a modified version of Luke Gorrie's pmap -
 %% http://lukego.livejournal.com/6753.html - that doesn't care about
@@ -541,6 +556,11 @@ dirty_dump_log1(LH, {K, Terms, BadBytes}) ->
     io:format("Bad Chunk, ~p: ~p~n", [BadBytes, Terms]),
     dirty_dump_log1(LH, disk_log:chunk(LH, K)).
 
+format(Fmt, Args) -> lists:flatten(io_lib:format(Fmt, Args)).
+
+format_many(List) ->
+    lists:flatten([io_lib:format(F ++ "~n", A) || {F, A} <- List]).
+
 format_stderr(Fmt, Args) ->
     case os:type() of
         {unix, _} ->
@@ -636,7 +656,7 @@ pid_to_string(Pid) when is_pid(Pid) ->
     <<131,103,100,NodeLen:16,NodeBin:NodeLen/binary,Id:32,Ser:32,Cre:8>>
         = term_to_binary(Pid),
     Node = binary_to_term(<<131,100,NodeLen:16,NodeBin:NodeLen/binary>>),
-    lists:flatten(io_lib:format("<~w.~B.~B.~B>", [Node, Cre, Id, Ser])).
+    format("<~w.~B.~B.~B>", [Node, Cre, Id, Ser]).
 
 %% inverse of above
 string_to_pid(Str) ->
@@ -720,38 +740,63 @@ gb_trees_fold1(Fun, Acc, {Key, Val, It}) ->
 gb_trees_foreach(Fun, Tree) ->
     gb_trees_fold(fun (Key, Val, Acc) -> Fun(Key, Val), Acc end, ok, Tree).
 
-%% Separate flags and options from arguments.
-%% get_options([{flag, "-q"}, {option, "-p", "/"}],
-%%             ["set_permissions","-p","/","guest",
-%%              "-q",".*",".*",".*"])
-%% == {["set_permissions","guest",".*",".*",".*"],
-%%     [{"-q",true},{"-p","/"}]}
-get_options(Defs, As) ->
-    lists:foldl(fun(Def, {AsIn, RsIn}) ->
-                        {AsOut, Value} = case Def of
-                                             {flag, Key} ->
-                                                 get_flag(Key, AsIn);
-                                             {option, Key, Default} ->
-                                                 get_option(Key, Default, AsIn)
-                                         end,
-                        {AsOut, [{Key, Value} | RsIn]}
-                end, {As, []}, Defs).
-
-get_option(K, _Default, [K, V | As]) ->
-    {As, V};
-get_option(K, Default, [Nk | As]) ->
-    {As1, V} = get_option(K, Default, As),
-    {[Nk | As1], V};
-get_option(_, Default, As) ->
-    {As, Default}.
-
-get_flag(K, [K | As]) ->
-    {As, true};
-get_flag(K, [Nk | As]) ->
-    {As1, V} = get_flag(K, As),
-    {[Nk | As1], V};
-get_flag(_, []) ->
-    {[], false}.
+%% Takes:
+%%    * A list of [{atom(), [{string(), optdef()]} | atom()], where the atom()s
+%%      are the accepted commands and the optional [string()] is the list of
+%%      accepted options for that command
+%%    * A list [{string(), optdef()}] of options valid for all commands
+%%    * The list of arguments given by the user
+%%
+%% Returns either {ok, {atom(), [{string(), string()}], [string()]} which are
+%% respectively the command, the key-value pairs of the options and the leftover
+%% arguments; or no_command if no command could be parsed.
+parse_arguments(Commands, GlobalDefs, As) ->
+    lists:foldl(maybe_process_opts(GlobalDefs, As), no_command, Commands).
+
+maybe_process_opts(GDefs, As) ->
+    fun({C, Os}, no_command) ->
+            process_opts(atom_to_list(C), dict:from_list(GDefs ++ Os), As);
+       (C, no_command) ->
+            (maybe_process_opts(GDefs, As))({C, []}, no_command);
+       (_, {ok, Res}) ->
+            {ok, Res}
+    end.
+
+process_opts(C, Defs, As0) ->
+    KVs0 = dict:map(fun (_, flag)        -> false;
+                        (_, {option, V}) -> V
+                    end, Defs),
+    process_opts(Defs, C, As0, not_found, KVs0, []).
+
+%% Consume flags/options until you find the correct command. If there are no
+%% arguments or the first argument is not the command we're expecting, fail.
+%% Arguments to this are: definitions, cmd we're looking for, args we
+%% haven't parsed, whether we have found the cmd, options we've found,
+%% plain args we've found.
+process_opts(_Defs, C, [], found, KVs, Outs) ->
+    {ok, {list_to_atom(C), dict:to_list(KVs), lists:reverse(Outs)}};
+process_opts(_Defs, _C, [], not_found, _, _) ->
+    no_command;
+process_opts(Defs, C, [A | As], Found, KVs, Outs) ->
+    OptType = case dict:find(A, Defs) of
+                  error             -> none;
+                  {ok, flag}        -> flag;
+                  {ok, {option, _}} -> option
+              end,
+    case {OptType, C, Found} of
+        {flag, _, _}     -> process_opts(
+                              Defs, C, As, Found, dict:store(A, true, KVs),
+                              Outs);
+        {option, _, _}   -> case As of
+                                []        -> no_command;
+                                [V | As1] -> process_opts(
+                                               Defs, C, As1, Found,
+                                               dict:store(A, V, KVs), Outs)
+                            end;
+        {none, A, _}     -> process_opts(Defs, C, As, found, KVs, Outs);
+        {none, _, found} -> process_opts(Defs, C, As, found, KVs, [A | Outs]);
+        {none, _, _}     -> no_command
+    end.
 
 now_ms() ->
     timer:now_diff(now(), {0,0,0}) div 1000.
@@ -837,6 +882,8 @@ pget_or_die(K, P) ->
         V         -> V
     end.
 
+pset(Key, Value, List) -> [{Key, Value} | proplists:delete(Key, List)].
+
 format_message_queue(_Opt, MQ) ->
     Len = priority_queue:len(MQ),
     {Len,
@@ -865,9 +912,44 @@ append_rpc_all_nodes(Nodes, M, F, A) ->
                       _           -> Res
                   end || Res <- ResL]).
 
+%% A simplified version of gen_server:multi_call/2 with a sane
+%% API. This is not in gen_server2 as there is no useful
+%% infrastructure there to share.
+multi_call(Pids, Req) ->
+    MonitorPids = [start_multi_call(Pid, Req) || Pid <- Pids],
+    receive_multi_call(MonitorPids, [], []).
+
+start_multi_call(Pid, Req) when is_pid(Pid) ->
+    Mref = erlang:monitor(process, Pid),
+    Pid ! {'$gen_call', {self(), Mref}, Req},
+    {Mref, Pid}.
+
+receive_multi_call([], Good, Bad) ->
+    {lists:reverse(Good), lists:reverse(Bad)};
+receive_multi_call([{Mref, Pid} | MonitorPids], Good, Bad) ->
+    receive
+        {Mref, Reply} ->
+            erlang:demonitor(Mref, [flush]),
+            receive_multi_call(MonitorPids, [{Pid, Reply} | Good], Bad);
+        {'DOWN', Mref, _, _, noconnection} ->
+            receive_multi_call(MonitorPids, Good, [{Pid, nodedown} | Bad]);
+        {'DOWN', Mref, _, _, Reason} ->
+            receive_multi_call(MonitorPids, Good, [{Pid, Reason} | Bad])
+    end.
+
 %% the slower shutdown on windows required to flush stdout
 quit(Status) ->
     case os:type() of
         {unix,  _} -> halt(Status);
         {win32, _} -> init:stop(Status)
     end.
+
+os_cmd(Command) ->
+    Exec = hd(string:tokens(Command, " ")),
+    case os:find_executable(Exec) of
+        false -> throw({command_not_found, Exec});
+        _     -> os:cmd(Command)
+    end.
+
+gb_sets_difference(S1, S2) ->
+    gb_sets:fold(fun gb_sets:delete_any/2, S1, S2).
diff --git a/src/rabbit_mnesia.erl b/src/rabbit_mnesia.erl
index c8c18843..7e9346f9 100644
--- a/src/rabbit_mnesia.erl
+++ b/src/rabbit_mnesia.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 
@@ -23,8 +23,8 @@
          empty_ram_only_tables/0, copy_db/1, wait_for_tables/1,
          create_cluster_nodes_config/1, read_cluster_nodes_config/0,
          record_running_nodes/0, read_previously_running_nodes/0,
-         delete_previously_running_nodes/0, running_nodes_filename/0,
-         is_disc_node/0, on_node_down/1, on_node_up/1]).
+         running_nodes_filename/0, is_disc_node/0, on_node_down/1,
+         on_node_up/1]).
 
 -export([table_names/0]).
 
@@ -64,7 +64,6 @@
 -spec(read_cluster_nodes_config/0 :: () ->  [node()]).
 -spec(record_running_nodes/0 :: () ->  'ok').
 -spec(read_previously_running_nodes/0 :: () ->  [node()]).
--spec(delete_previously_running_nodes/0 :: () ->  'ok').
 -spec(running_nodes_filename/0 :: () -> file:filename()).
 -spec(is_disc_node/0 :: () -> boolean()).
 -spec(on_node_up/1 :: (node()) -> 'ok').
@@ -98,12 +97,13 @@ status() ->
 init() ->
     ensure_mnesia_running(),
     ensure_mnesia_dir(),
-    ok = init_db(read_cluster_nodes_config(), true,
-                 fun maybe_upgrade_local_or_record_desired/0),
+    Nodes = read_cluster_nodes_config(),
+    ok = init_db(Nodes, should_be_disc_node(Nodes)),
     %% We intuitively expect the global name server to be synced when
     %% Mnesia is up. In fact that's not guaranteed to be the case - let's
     %% make it so.
     ok = global:sync(),
+    ok = delete_previously_running_nodes(),
     ok.
 
 is_db_empty() ->
@@ -174,8 +174,7 @@ cluster(ClusterNodes, Force) ->
     %% Join the cluster
     start_mnesia(),
     try
-        ok = init_db(ClusterNodes, Force,
-                     fun maybe_upgrade_local_or_record_desired/0),
+        ok = init_db(ClusterNodes, Force),
         ok = create_cluster_nodes_config(ClusterNodes)
     after
         stop_mnesia()
@@ -268,6 +267,11 @@ table_definitions() ->
        {type, ordered_set},
        {match, #reverse_route{reverse_binding = reverse_binding_match(),
                               _='_'}}]},
+     {rabbit_topic_trie_node,
+      [{record_name, topic_trie_node},
+       {attributes, record_info(fields, topic_trie_node)},
+       {type, ordered_set},
+       {match, #topic_trie_node{trie_node = trie_node_match(), _='_'}}]},
      {rabbit_topic_trie_edge,
       [{record_name, topic_trie_edge},
        {attributes, record_info(fields, topic_trie_edge)},
@@ -292,6 +296,11 @@ table_definitions() ->
       [{record_name, exchange_serial},
        {attributes, record_info(fields, exchange_serial)},
        {match, #exchange_serial{name = exchange_name_match(), _='_'}}]},
+     {rabbit_runtime_parameters,
+      [{record_name, runtime_parameters},
+       {attributes, record_info(fields, runtime_parameters)},
+       {disc_copies, [node()]},
+       {match, #runtime_parameters{_='_'}}]},
      {rabbit_durable_queue,
       [{record_name, amqqueue},
        {attributes, record_info(fields, amqqueue)},
@@ -314,12 +323,12 @@ reverse_binding_match() ->
                      _='_'}.
 binding_destination_match() ->
     resource_match('_').
+trie_node_match() ->
+    #trie_node{   exchange_name = exchange_name_match(), _='_'}.
 trie_edge_match() ->
-    #trie_edge{exchange_name = exchange_name_match(),
-               _='_'}.
+    #trie_edge{   exchange_name = exchange_name_match(), _='_'}.
 trie_binding_match() ->
-    #trie_binding{exchange_name = exchange_name_match(),
-                  _='_'}.
+    #trie_binding{exchange_name = exchange_name_match(), _='_'}.
 exchange_name_match() ->
     resource_match(exchange).
 queue_name_match() ->
@@ -496,6 +505,18 @@ delete_previously_running_nodes() ->
                                           FileName, Reason}})
     end.
 
+init_db(ClusterNodes, Force) ->
+    init_db(
+      ClusterNodes, Force,
+      fun () ->
+              case rabbit_upgrade:maybe_upgrade_local() of
+                  ok                    -> ok;
+                  %% If we're just starting up a new node we won't have a
+                  %% version
+                  starting_from_scratch -> ok = rabbit_version:record_desired()
+              end
+      end).
+
 %% Take a cluster node config and create the right kind of node - a
 %% standalone disk node, or disk or ram node connected to the
 %% specified cluster nodes.  If Force is false, don't allow
@@ -504,20 +525,12 @@ init_db(ClusterNodes, Force, SecondaryPostMnesiaFun) ->
     UClusterNodes = lists:usort(ClusterNodes),
     ProperClusterNodes = UClusterNodes -- [node()],
     case mnesia:change_config(extra_db_nodes, ProperClusterNodes) of
+        {ok, []} when not Force andalso ProperClusterNodes =/= [] ->
+            throw({error, {failed_to_cluster_with, ProperClusterNodes,
+                           "Mnesia could not connect to any disc nodes."}});
         {ok, Nodes} ->
-            case Force of
-                false -> FailedClusterNodes = ProperClusterNodes -- Nodes,
-                         case FailedClusterNodes of
-                             [] -> ok;
-                             _  -> throw({error, {failed_to_cluster_with,
-                                                  FailedClusterNodes,
-                                                  "Mnesia could not connect "
-                                                  "to some nodes."}})
-                         end;
-                true  -> ok
-            end,
-            WantDiscNode = should_be_disc_node(ClusterNodes),
             WasDiscNode = is_disc_node(),
+            WantDiscNode = should_be_disc_node(ClusterNodes),
             %% We create a new db (on disk, or in ram) in the first
             %% two cases and attempt to upgrade the in the other two
             case {Nodes, WasDiscNode, WantDiscNode} of
@@ -567,14 +580,6 @@ init_db(ClusterNodes, Force, SecondaryPostMnesiaFun) ->
             throw({error, {unable_to_join_cluster, ClusterNodes, Reason}})
     end.
 
-maybe_upgrade_local_or_record_desired() ->
-    case rabbit_upgrade:maybe_upgrade_local() of
-        ok                    -> ok;
-        %% If we're just starting up a new node we won't have a
-        %% version
-        version_not_available -> ok = rabbit_version:record_desired()
-    end.
-
 schema_ok_or_move() ->
     case check_schema_integrity() of
         ok ->
@@ -622,10 +627,9 @@ move_db() ->
     stop_mnesia(),
     MnesiaDir = filename:dirname(dir() ++ "/"),
     {{Year, Month, Day}, {Hour, Minute, Second}} = erlang:universaltime(),
-    BackupDir = lists:flatten(
-                  io_lib:format("~s_~w~2..0w~2..0w~2..0w~2..0w~2..0w",
-                                [MnesiaDir,
-                                 Year, Month, Day, Hour, Minute, Second])),
+    BackupDir = rabbit_misc:format(
+                  "~s_~w~2..0w~2..0w~2..0w~2..0w~2..0w",
+                  [MnesiaDir, Year, Month, Day, Hour, Minute, Second]),
     case file:rename(MnesiaDir, BackupDir) of
         ok ->
             %% NB: we cannot use rabbit_log here since it may not have
@@ -733,16 +737,18 @@ reset(Force) ->
         false -> ok
     end,
     Node = node(),
+    Nodes = all_clustered_nodes() -- [Node],
     case Force of
         true  -> ok;
         false ->
             ensure_mnesia_dir(),
             start_mnesia(),
-            {Nodes, RunningNodes} =
+            RunningNodes =
                 try
-                    ok = init(),
-                    {all_clustered_nodes() -- [Node],
-                     running_clustered_nodes() -- [Node]}
+                    %% Force=true here so that reset still works when clustered
+                    %% with a node which is down
+                    ok = init_db(read_cluster_nodes_config(), true),
+                    running_clustered_nodes() -- [Node]
                 after
                     stop_mnesia()
                 end,
@@ -750,6 +756,10 @@ reset(Force) ->
             rabbit_misc:ensure_ok(mnesia:delete_schema([Node]),
                                   cannot_delete_schema)
     end,
+    %% We need to make sure that we don't end up in a distributed
+    %% Erlang system with nodes while not being in an Mnesia cluster
+    %% with them. We don't handle that well.
+    [erlang:disconnect_node(N) || N <- Nodes],
     ok = delete_cluster_nodes_config(),
     %% remove persisted messages and any other garbage we find
     ok = rabbit_file:recursive_delete(filelib:wildcard(dir() ++ "/*")),
diff --git a/src/rabbit_msg_file.erl b/src/rabbit_msg_file.erl
index b7de27d4..f685b109 100644
--- a/src/rabbit_msg_file.erl
+++ b/src/rabbit_msg_file.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_msg_file).
diff --git a/src/rabbit_msg_store.erl b/src/rabbit_msg_store.erl
index e6a32b90..d69dad1f 100644
--- a/src/rabbit_msg_store.erl
+++ b/src/rabbit_msg_store.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_msg_store).
@@ -21,7 +21,7 @@
 -export([start_link/4, successfully_recovered_state/1,
          client_init/4, client_terminate/1, client_delete_and_terminate/1,
          client_ref/1, close_all_indicated/1,
-         write/3, read/2, contains/2, remove/2]).
+         write/3, write_flow/3, read/2, contains/2, remove/2]).
 
 -export([set_maximum_since_use/2, has_readers/2, combine_files/3,
          delete_file/2]). %% internal
@@ -152,6 +152,7 @@
 -spec(close_all_indicated/1 ::
         (client_msstate()) -> rabbit_types:ok(client_msstate())).
 -spec(write/3 :: (rabbit_types:msg_id(), msg(), client_msstate()) -> 'ok').
+-spec(write_flow/3 :: (rabbit_types:msg_id(), msg(), client_msstate()) -> 'ok').
 -spec(read/2 :: (rabbit_types:msg_id(), client_msstate()) ->
                      {rabbit_types:ok(msg()) | 'not_found', client_msstate()}).
 -spec(contains/2 :: (rabbit_types:msg_id(), client_msstate()) -> boolean()).
@@ -436,7 +437,8 @@ client_init(Server, Ref, MsgOnDiskFun, CloseFDsFun) ->
     {IState, IModule, Dir, GCPid,
      FileHandlesEts, FileSummaryEts, CurFileCacheEts, FlyingEts} =
         gen_server2:call(
-          Server, {new_client_state, Ref, MsgOnDiskFun, CloseFDsFun}, infinity),
+          Server, {new_client_state, Ref, self(), MsgOnDiskFun, CloseFDsFun},
+          infinity),
     #client_msstate { server             = Server,
                       client_ref         = Ref,
                       file_handle_cache  = dict:new(),
@@ -460,12 +462,11 @@ client_delete_and_terminate(CState = #client_msstate { client_ref = Ref }) ->
 
 client_ref(#client_msstate { client_ref = Ref }) -> Ref.
 
-write(MsgId, Msg,
-      CState = #client_msstate { cur_file_cache_ets = CurFileCacheEts,
-                                 client_ref         = CRef }) ->
-    ok = client_update_flying(+1, MsgId, CState),
-    ok = update_msg_cache(CurFileCacheEts, MsgId, Msg),
-    ok = server_cast(CState, {write, CRef, MsgId}).
+write_flow(MsgId, Msg, CState = #client_msstate { server = Server }) ->
+    credit_flow:send(whereis(Server), ?CREDIT_DISC_BOUND),
+    client_write(MsgId, Msg, flow, CState).
+
+write(MsgId, Msg, CState) -> client_write(MsgId, Msg, noflow, CState).
 
 read(MsgId,
      CState = #client_msstate { cur_file_cache_ets = CurFileCacheEts }) ->
@@ -500,6 +501,13 @@ server_call(#client_msstate { server = Server }, Msg) ->
 server_cast(#client_msstate { server = Server }, Msg) ->
     gen_server2:cast(Server, Msg).
 
+client_write(MsgId, Msg, Flow,
+             CState = #client_msstate { cur_file_cache_ets = CurFileCacheEts,
+                                        client_ref         = CRef }) ->
+    ok = client_update_flying(+1, MsgId, CState),
+    ok = update_msg_cache(CurFileCacheEts, MsgId, Msg),
+    ok = server_cast(CState, {write, CRef, MsgId, Flow}).
+
 client_read1(#msg_location { msg_id = MsgId, file = File } = MsgLocation, Defer,
              CState = #client_msstate { file_summary_ets = FileSummaryEts }) ->
     case ets:lookup(FileSummaryEts, File) of
@@ -666,7 +674,8 @@ init([Server, BaseDir, ClientRefs, StartupFunState]) ->
         recover_index_and_client_refs(IndexModule, FileSummaryRecovered,
                                       ClientRefs, Dir, Server),
     Clients = dict:from_list(
-                [{CRef, {undefined, undefined}} || CRef <- ClientRefs1]),
+                [{CRef, {undefined, undefined, undefined}} ||
+                    CRef <- ClientRefs1]),
     %% CleanShutdown => msg location index and file_summary both
     %% recovered correctly.
     true = case {FileSummaryRecovered, CleanShutdown} of
@@ -731,10 +740,10 @@ init([Server, BaseDir, ClientRefs, StartupFunState]) ->
 
 prioritise_call(Msg, _From, _State) ->
     case Msg of
-        successfully_recovered_state                  -> 7;
-        {new_client_state, _Ref, _MODC, _CloseFDsFun} -> 7;
-        {read, _MsgId}                                -> 2;
-        _                                             -> 0
+        successfully_recovered_state                        -> 7;
+        {new_client_state, _Ref, _Pid, _MODC, _CloseFDsFun} -> 7;
+        {read, _MsgId}                                      -> 2;
+        _                                                   -> 0
     end.
 
 prioritise_cast(Msg, _State) ->
@@ -755,7 +764,7 @@ prioritise_info(Msg, _State) ->
 handle_call(successfully_recovered_state, _From, State) ->
     reply(State #msstate.successfully_recovered, State);
 
-handle_call({new_client_state, CRef, MsgOnDiskFun, CloseFDsFun}, _From,
+handle_call({new_client_state, CRef, CPid, MsgOnDiskFun, CloseFDsFun}, _From,
             State = #msstate { dir                = Dir,
                                index_state        = IndexState,
                                index_module       = IndexModule,
@@ -765,7 +774,7 @@ handle_call({new_client_state, CRef, MsgOnDiskFun, CloseFDsFun}, _From,
                                flying_ets         = FlyingEts,
                                clients            = Clients,
                                gc_pid             = GCPid }) ->
-    Clients1 = dict:store(CRef, {MsgOnDiskFun, CloseFDsFun}, Clients),
+    Clients1 = dict:store(CRef, {CPid, MsgOnDiskFun, CloseFDsFun}, Clients),
     reply({IndexState, IndexModule, Dir, GCPid, FileHandlesEts, FileSummaryEts,
            CurFileCacheEts, FlyingEts},
           State #msstate { clients = Clients1 });
@@ -789,11 +798,19 @@ handle_cast({client_dying, CRef},
 
 handle_cast({client_delete, CRef},
             State = #msstate { clients = Clients }) ->
+    {CPid, _, _} = dict:fetch(CRef, Clients),
+    credit_flow:peer_down(CPid),
     State1 = State #msstate { clients = dict:erase(CRef, Clients) },
     noreply(remove_message(CRef, CRef, clear_client(CRef, State1)));
 
-handle_cast({write, CRef, MsgId},
-            State = #msstate { cur_file_cache_ets = CurFileCacheEts }) ->
+handle_cast({write, CRef, MsgId, Flow},
+            State = #msstate { cur_file_cache_ets = CurFileCacheEts,
+                               clients            = Clients }) ->
+    case Flow of
+        flow   -> {CPid, _, _} = dict:fetch(CRef, Clients),
+                  credit_flow:ack(CPid, ?CREDIT_DISC_BOUND);
+        noflow -> ok
+    end,
     true = 0 =< ets:update_counter(CurFileCacheEts, MsgId, {3, -1}),
     case update_flying(-1, MsgId, CRef, State) of
         process ->
@@ -1204,10 +1221,10 @@ update_pending_confirms(Fun, CRef,
                         State = #msstate { clients         = Clients,
                                            cref_to_msg_ids = CTM }) ->
     case dict:fetch(CRef, Clients) of
-        {undefined,    _CloseFDsFun} -> State;
-        {MsgOnDiskFun, _CloseFDsFun} -> CTM1 = Fun(MsgOnDiskFun, CTM),
-                                        State #msstate {
-                                          cref_to_msg_ids = CTM1 }
+        {_CPid, undefined,    _CloseFDsFun} -> State;
+        {_CPid, MsgOnDiskFun, _CloseFDsFun} -> CTM1 = Fun(MsgOnDiskFun, CTM),
+                                               State #msstate {
+                                                 cref_to_msg_ids = CTM1 }
     end.
 
 record_pending_confirm(CRef, MsgId, State) ->
@@ -1223,7 +1240,8 @@ client_confirm(CRef, MsgIds, ActionTaken, State) ->
               case dict:find(CRef, CTM) of
                   {ok, Gs} -> MsgOnDiskFun(gb_sets:intersection(Gs, MsgIds),
                                            ActionTaken),
-                              MsgIds1 = gb_sets:difference(Gs, MsgIds),
+                              MsgIds1 = rabbit_misc:gb_sets_difference(
+                                          Gs, MsgIds),
                               case gb_sets:is_empty(MsgIds1) of
                                   true  -> dict:erase(CRef, CTM);
                                   false -> dict:store(CRef, MsgIds1, CTM)
@@ -1294,8 +1312,10 @@ mark_handle_to_close(ClientRefs, FileHandlesEts, File, Invoke) ->
           case (ets:update_element(FileHandlesEts, Key, {2, close})
                 andalso Invoke) of
               true  -> case dict:fetch(Ref, ClientRefs) of
-                           {_MsgOnDiskFun, undefined}   -> ok;
-                           {_MsgOnDiskFun, CloseFDsFun} -> ok = CloseFDsFun()
+                           {_CPid, _MsgOnDiskFun, undefined} ->
+                               ok;
+                           {_CPid, _MsgOnDiskFun, CloseFDsFun} ->
+                               ok = CloseFDsFun()
                        end;
               false -> ok
           end
diff --git a/src/rabbit_msg_store_ets_index.erl b/src/rabbit_msg_store_ets_index.erl
index d6dc5568..3defeaaf 100644
--- a/src/rabbit_msg_store_ets_index.erl
+++ b/src/rabbit_msg_store_ets_index.erl
@@ -11,11 +11,13 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_msg_store_ets_index).
 
+-include("rabbit_msg_store.hrl").
+
 -behaviour(rabbit_msg_store_index).
 
 -export([new/1, recover/1,
@@ -25,8 +27,6 @@
 -define(MSG_LOC_NAME, rabbit_msg_store_ets_index).
 -define(FILENAME, "msg_store_index.ets").
 
--include("rabbit_msg_store_index.hrl").
-
 -record(state, { table, dir }).
 
 new(Dir) ->
diff --git a/src/rabbit_msg_store_gc.erl b/src/rabbit_msg_store_gc.erl
index 77f1f04e..3b61ed0b 100644
--- a/src/rabbit_msg_store_gc.erl
+++ b/src/rabbit_msg_store_gc.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_msg_store_gc).
diff --git a/src/rabbit_msg_store_index.erl b/src/rabbit_msg_store_index.erl
index ef8b7cdf..6cc0b2a7 100644
--- a/src/rabbit_msg_store_index.erl
+++ b/src/rabbit_msg_store_index.erl
@@ -11,11 +11,36 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_msg_store_index).
 
+-include("rabbit_msg_store.hrl").
+
+-ifdef(use_specs).
+
+-type(dir() :: any()).
+-type(index_state() :: any()).
+-type(keyvalue() :: any()).
+-type(fieldpos() :: non_neg_integer()).
+-type(fieldvalue() :: any()).
+
+-callback new(dir()) -> index_state().
+-callback recover(dir()) -> rabbit_types:ok_or_error2(index_state(), any()).
+-callback lookup(rabbit_types:msg_id(), index_state()) -> ('not_found' | keyvalue()).
+-callback insert(keyvalue(), index_state()) -> 'ok'.
+-callback update(keyvalue(), index_state()) -> 'ok'.
+-callback update_fields(rabbit_types:msg_id(), ({fieldpos(), fieldvalue()} |
+                                                [{fieldpos(), fieldvalue()}]),
+                        index_state()) -> 'ok'.
+-callback delete(rabbit_types:msg_id(), index_state()) -> 'ok'.
+-callback delete_object(keyvalue(), index_state()) -> 'ok'.
+-callback delete_by_file(fieldvalue(), index_state()) -> 'ok'.
+-callback terminate(index_state()) -> any().
+
+-else.
+
 -export([behaviour_info/1]).
 
 behaviour_info(callbacks) ->
@@ -30,3 +55,5 @@ behaviour_info(callbacks) ->
      {terminate,      1}];
 behaviour_info(_Other) ->
     undefined.
+
+-endif.
diff --git a/src/rabbit_net.erl b/src/rabbit_net.erl
index b944ec81..1a12d43b 100644
--- a/src/rabbit_net.erl
+++ b/src/rabbit_net.erl
@@ -11,15 +11,16 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_net).
 -include("rabbit.hrl").
 
 -export([is_ssl/1, ssl_info/1, controlling_process/2, getstat/2,
-         recv/1, async_recv/3, port_command/2, setopts/2, send/2, close/1,
-         sockname/1, peername/1, peercert/1]).
+         recv/1, async_recv/3, port_command/2, getopts/2, setopts/2, send/2,
+         close/1, maybe_fast_close/1, sockname/1, peername/1, peercert/1,
+         connection_string/2]).
 
 %%---------------------------------------------------------------------------
 
@@ -33,6 +34,8 @@
 -type(ok_val_or_error(A) :: rabbit_types:ok_or_error2(A, any())).
 -type(ok_or_any_error() :: rabbit_types:ok_or_error(any())).
 -type(socket() :: port() | #ssl_socket{}).
+-type(opts() :: [{atom(), any()} |
+                 {raw, non_neg_integer(), non_neg_integer(), binary()}]).
 
 -spec(is_ssl/1 :: (socket()) -> boolean()).
 -spec(ssl_info/1 :: (socket())
@@ -48,11 +51,15 @@
 -spec(async_recv/3 ::
         (socket(), integer(), timeout()) -> rabbit_types:ok(any())).
 -spec(port_command/2 :: (socket(), iolist()) -> 'true').
--spec(setopts/2 :: (socket(), [{atom(), any()} |
-                               {raw, non_neg_integer(), non_neg_integer(),
-                                binary()}]) -> ok_or_any_error()).
+-spec(getopts/2 :: (socket(), [atom() | {raw,
+                                         non_neg_integer(),
+                                         non_neg_integer(),
+                                         non_neg_integer() | binary()}])
+                   -> ok_val_or_error(opts())).
+-spec(setopts/2 :: (socket(), opts()) -> ok_or_any_error()).
 -spec(send/2 :: (socket(), binary() | iolist()) -> ok_or_any_error()).
 -spec(close/1 :: (socket()) -> ok_or_any_error()).
+-spec(maybe_fast_close/1 :: (socket()) -> ok_or_any_error()).
 -spec(sockname/1 ::
         (socket())
         -> ok_val_or_error({inet:ip_address(), rabbit_networking:ip_port()})).
@@ -62,6 +69,8 @@
 -spec(peercert/1 ::
         (socket())
         -> 'nossl' | ok_val_or_error(rabbit_ssl:certificate())).
+-spec(connection_string/2 ::
+        (socket(), 'inbound' | 'outbound') -> ok_val_or_error(string())).
 
 -endif.
 
@@ -122,6 +131,11 @@ port_command(Sock, Data) when ?IS_SSL(Sock) ->
 port_command(Sock, Data) when is_port(Sock) ->
     erlang:port_command(Sock, Data).
 
+getopts(Sock, Options) when ?IS_SSL(Sock) ->
+    ssl:getopts(Sock#ssl_socket.ssl, Options);
+getopts(Sock, Options) when is_port(Sock) ->
+    inet:getopts(Sock, Options).
+
 setopts(Sock, Options) when ?IS_SSL(Sock) ->
     ssl:setopts(Sock#ssl_socket.ssl, Options);
 setopts(Sock, Options) when is_port(Sock) ->
@@ -133,6 +147,9 @@ send(Sock, Data) when is_port(Sock) -> gen_tcp:send(Sock, Data).
 close(Sock)      when ?IS_SSL(Sock) -> ssl:close(Sock#ssl_socket.ssl);
 close(Sock)      when is_port(Sock) -> gen_tcp:close(Sock).
 
+maybe_fast_close(Sock) when ?IS_SSL(Sock) -> ok;
+maybe_fast_close(Sock) when is_port(Sock) -> erlang:port_close(Sock), ok.
+
 sockname(Sock)   when ?IS_SSL(Sock) -> ssl:sockname(Sock#ssl_socket.ssl);
 sockname(Sock)   when is_port(Sock) -> inet:sockname(Sock).
 
@@ -141,3 +158,19 @@ peername(Sock)   when is_port(Sock) -> inet:peername(Sock).
 
 peercert(Sock)   when ?IS_SSL(Sock) -> ssl:peercert(Sock#ssl_socket.ssl);
 peercert(Sock)   when is_port(Sock) -> nossl.
+
+connection_string(Sock, Direction) ->
+    {From, To} = case Direction of
+                     inbound  -> {fun peername/1, fun sockname/1};
+                     outbound -> {fun sockname/1, fun peername/1}
+                 end,
+    case {From(Sock), To(Sock)} of
+        {{ok, {FromAddress, FromPort}}, {ok, {ToAddress, ToPort}}} ->
+            {ok, rabbit_misc:format("~s:~p -> ~s:~p",
+                                    [rabbit_misc:ntoab(FromAddress), FromPort,
+                                     rabbit_misc:ntoab(ToAddress),   ToPort])};
+        {{error, _Reason} = Error, _} ->
+            Error;
+        {_, {error, _Reason} = Error} ->
+            Error
+    end.
diff --git a/src/rabbit_networking.erl b/src/rabbit_networking.erl
index 045ab89a..78deea97 100644
--- a/src/rabbit_networking.erl
+++ b/src/rabbit_networking.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_networking).
@@ -24,7 +24,7 @@
          close_connection/2, force_connection_event_refresh/0]).
 
 %%used by TCP-based transports, e.g. STOMP adapter
--export([check_tcp_listener_address/2,
+-export([tcp_listener_addresses/1, tcp_listener_spec/6,
          ensure_ssl/0, ssl_transform_fun/1]).
 
 -export([tcp_listener_started/3, tcp_listener_stopped/3,
@@ -47,12 +47,16 @@
 -export_type([ip_port/0, hostname/0]).
 
 -type(hostname() :: inet:hostname()).
--type(ip_port() :: inet:ip_port()).
+-type(ip_port() :: inet:port_number()).
 
 -type(family() :: atom()).
 -type(listener_config() :: ip_port() |
                            {hostname(), ip_port()} |
                            {hostname(), ip_port(), family()}).
+-type(address() :: {inet:ip_address(), ip_port(), family()}).
+-type(name_prefix() :: atom()).
+-type(protocol() :: atom()).
+-type(label() :: string()).
 
 -spec(start/0 :: () -> 'ok').
 -spec(start_tcp_listener/1 :: (listener_config()) -> 'ok').
@@ -76,8 +80,10 @@
 -spec(force_connection_event_refresh/0 :: () -> 'ok').
 
 -spec(on_node_down/1 :: (node()) -> 'ok').
--spec(check_tcp_listener_address/2 :: (atom(), listener_config())
-        -> [{inet:ip_address(), ip_port(), family(), atom()}]).
+-spec(tcp_listener_addresses/1 :: (listener_config()) -> [address()]).
+-spec(tcp_listener_spec/6 ::
+        (name_prefix(), address(), [gen_tcp:listen_option()], protocol(),
+         label(), rabbit_types:mfargs()) -> supervisor:child_spec()).
 -spec(ensure_ssl/0 :: () -> rabbit_types:infos()).
 -spec(ssl_transform_fun/1 ::
         (rabbit_types:infos())
@@ -130,48 +136,10 @@ boot_ssl() ->
             ok
     end.
 
-start() ->
-    {ok,_} = supervisor2:start_child(
-               rabbit_sup,
-               {rabbit_tcp_client_sup,
-                {rabbit_client_sup, start_link,
-                 [{local, rabbit_tcp_client_sup},
-                  {rabbit_connection_sup,start_link,[]}]},
-                transient, infinity, supervisor, [rabbit_client_sup]}),
-    ok.
-
-%% inet_parse:address takes care of ip string, like "0.0.0.0"
-%% inet:getaddr returns immediately for ip tuple {0,0,0,0},
-%%  and runs 'inet_gethost' port process for dns lookups.
-%% On Windows inet:getaddr runs dns resolver for ip string, which may fail.
-
-getaddr(Host, Family) ->
-    case inet_parse:address(Host) of
-        {ok, IPAddress} -> [{IPAddress, resolve_family(IPAddress, Family)}];
-        {error, _}      -> gethostaddr(Host, Family)
-    end.
-
-gethostaddr(Host, auto) ->
-    Lookups = [{Family, inet:getaddr(Host, Family)} || Family <- [inet, inet6]],
-    case [{IP, Family} || {Family, {ok, IP}} <- Lookups] of
-        []  -> host_lookup_error(Host, Lookups);
-        IPs -> IPs
-    end;
-
-gethostaddr(Host, Family) ->
-    case inet:getaddr(Host, Family) of
-        {ok, IPAddress} -> [{IPAddress, Family}];
-        {error, Reason} -> host_lookup_error(Host, Reason)
-    end.
-
-host_lookup_error(Host, Reason) ->
-    error_logger:error_msg("invalid host ~p - ~p~n", [Host, Reason]),
-    throw({error, {invalid_host, Host, Reason}}).
-
-resolve_family({_,_,_,_},         auto) -> inet;
-resolve_family({_,_,_,_,_,_,_,_}, auto) -> inet6;
-resolve_family(IP,                auto) -> throw({error, {strange_family, IP}});
-resolve_family(_,                 F)    -> F.
+start() -> rabbit_sup:start_supervisor_child(
+             rabbit_tcp_client_sup, rabbit_client_sup,
+             [{local, rabbit_tcp_client_sup},
+              {rabbit_connection_sup,start_link,[]}]).
 
 ensure_ssl() ->
     ok = rabbit_misc:start_applications([crypto, public_key, ssl]),
@@ -191,8 +159,6 @@ ssl_transform_fun(SslOpts) ->
     fun (Sock) ->
             case catch ssl:ssl_accept(Sock, SslOpts, ?SSL_TIMEOUT * 1000) of
                 {ok, SslSock} ->
-                    rabbit_log:info("upgraded TCP connection ~p to SSL~n",
-                                    [self()]),
                     {ok, #ssl_socket{tcp = Sock, ssl = SslSock}};
                 {error, Reason} ->
                     {error, {ssl_upgrade_error, Reason}};
@@ -201,31 +167,36 @@ ssl_transform_fun(SslOpts) ->
             end
     end.
 
-check_tcp_listener_address(NamePrefix, Port) when is_integer(Port) ->
-    check_tcp_listener_address_auto(NamePrefix, Port);
-
-check_tcp_listener_address(NamePrefix, {"auto", Port}) ->
+tcp_listener_addresses(Port) when is_integer(Port) ->
+    tcp_listener_addresses_auto(Port);
+tcp_listener_addresses({"auto", Port}) ->
     %% Variant to prevent lots of hacking around in bash and batch files
-    check_tcp_listener_address_auto(NamePrefix, Port);
-
-check_tcp_listener_address(NamePrefix, {Host, Port}) ->
+    tcp_listener_addresses_auto(Port);
+tcp_listener_addresses({Host, Port}) ->
     %% auto: determine family IPv4 / IPv6 after converting to IP address
-    check_tcp_listener_address(NamePrefix, {Host, Port, auto});
-
-check_tcp_listener_address(NamePrefix, {Host, Port, Family0}) ->
-    if is_integer(Port) andalso (Port >= 0) andalso (Port =< 65535) -> ok;
-       true -> error_logger:error_msg("invalid port ~p - not 0..65535~n",
-                                      [Port]),
-               throw({error, {invalid_port, Port}})
-    end,
-    [{IPAddress, Port, Family,
-      rabbit_misc:tcp_name(NamePrefix, IPAddress, Port)} ||
-        {IPAddress, Family} <- getaddr(Host, Family0)].
-
-check_tcp_listener_address_auto(NamePrefix, Port) ->
-    lists:append([check_tcp_listener_address(NamePrefix, Listener) ||
+    tcp_listener_addresses({Host, Port, auto});
+tcp_listener_addresses({Host, Port, Family0})
+  when is_integer(Port) andalso (Port >= 0) andalso (Port =< 65535) ->
+    [{IPAddress, Port, Family} ||
+        {IPAddress, Family} <- getaddr(Host, Family0)];
+tcp_listener_addresses({_Host, Port, _Family0}) ->
+    error_logger:error_msg("invalid port ~p - not 0..65535~n", [Port]),
+    throw({error, {invalid_port, Port}}).
+
+tcp_listener_addresses_auto(Port) ->
+    lists:append([tcp_listener_addresses(Listener) ||
                      Listener <- port_to_listeners(Port)]).
 
+tcp_listener_spec(NamePrefix, {IPAddress, Port, Family}, SocketOpts,
+                  Protocol, Label, OnConnect) ->
+    {rabbit_misc:tcp_name(NamePrefix, IPAddress, Port),
+     {tcp_listener_sup, start_link,
+      [IPAddress, Port, [Family | SocketOpts],
+       {?MODULE, tcp_listener_started, [Protocol]},
+       {?MODULE, tcp_listener_stopped, [Protocol]},
+       OnConnect, Label]},
+     transient, infinity, supervisor, [tcp_listener_sup]}.
+
 start_tcp_listener(Listener) ->
     start_listener(Listener, amqp, "TCP Listener",
                    {?MODULE, start_client, []}).
@@ -235,27 +206,26 @@ start_ssl_listener(Listener, SslOpts) ->
                    {?MODULE, start_ssl_client, [SslOpts]}).
 
 start_listener(Listener, Protocol, Label, OnConnect) ->
-    [start_listener0(Spec, Protocol, Label, OnConnect) ||
-        Spec <- check_tcp_listener_address(rabbit_tcp_listener_sup, Listener)],
+    [start_listener0(Address, Protocol, Label, OnConnect) ||
+        Address <- tcp_listener_addresses(Listener)],
     ok.
 
-start_listener0({IPAddress, Port, Family, Name}, Protocol, Label, OnConnect) ->
-    {ok,_} = supervisor:start_child(
-               rabbit_sup,
-               {Name,
-                {tcp_listener_sup, start_link,
-                 [IPAddress, Port, [Family | tcp_opts()],
-                  {?MODULE, tcp_listener_started, [Protocol]},
-                  {?MODULE, tcp_listener_stopped, [Protocol]},
-                  OnConnect, Label]},
-                transient, infinity, supervisor, [tcp_listener_sup]}).
+start_listener0(Address, Protocol, Label, OnConnect) ->
+    Spec = tcp_listener_spec(rabbit_tcp_listener_sup, Address, tcp_opts(),
+                             Protocol, Label, OnConnect),
+    case supervisor:start_child(rabbit_sup, Spec) of
+        {ok, _}                -> ok;
+        {error, {shutdown, _}} -> {IPAddress, Port, _Family} = Address,
+                                  exit({could_not_start_tcp_listener,
+                                        {rabbit_misc:ntoa(IPAddress), Port}})
+    end.
 
 stop_tcp_listener(Listener) ->
-    [stop_tcp_listener0(Spec) ||
-        Spec <- check_tcp_listener_address(rabbit_tcp_listener_sup, Listener)],
+    [stop_tcp_listener0(Address) ||
+        Address <- tcp_listener_addresses(Listener)],
     ok.
 
-stop_tcp_listener0({IPAddress, Port, _Family, Name}) ->
+stop_tcp_listener0({IPAddress, Port, _Family}) ->
     Name = rabbit_misc:tcp_name(rabbit_tcp_listener_sup, IPAddress, Port),
     ok = supervisor:terminate_child(rabbit_sup, Name),
     ok = supervisor:delete_child(rabbit_sup, Name).
@@ -294,6 +264,16 @@ start_client(Sock, SockTransform) ->
     {ok, _Child, Reader} = supervisor:start_child(rabbit_tcp_client_sup, []),
     ok = rabbit_net:controlling_process(Sock, Reader),
     Reader ! {go, Sock, SockTransform},
+
+    %% In the event that somebody floods us with connections, the
+    %% reader processes can spew log events at error_logger faster
+    %% than it can keep up, causing its mailbox to grow unbounded
+    %% until we eat all the memory available and crash. So here is a
+    %% meaningless synchronous call to the underlying gen_event
+    %% mechanism. When it returns the mailbox is drained, and we
+    %% return to our caller to accept more connetions.
+    gen_event:which_handlers(error_logger),
+
     Reader.
 
 start_client(Sock) ->
@@ -363,6 +343,38 @@ tcp_opts() ->
     {ok, Opts} = application:get_env(rabbit, tcp_listen_options),
     Opts.
 
+%% inet_parse:address takes care of ip string, like "0.0.0.0"
+%% inet:getaddr returns immediately for ip tuple {0,0,0,0},
+%%  and runs 'inet_gethost' port process for dns lookups.
+%% On Windows inet:getaddr runs dns resolver for ip string, which may fail.
+getaddr(Host, Family) ->
+    case inet_parse:address(Host) of
+        {ok, IPAddress} -> [{IPAddress, resolve_family(IPAddress, Family)}];
+        {error, _}      -> gethostaddr(Host, Family)
+    end.
+
+gethostaddr(Host, auto) ->
+    Lookups = [{Family, inet:getaddr(Host, Family)} || Family <- [inet, inet6]],
+    case [{IP, Family} || {Family, {ok, IP}} <- Lookups] of
+        []  -> host_lookup_error(Host, Lookups);
+        IPs -> IPs
+    end;
+
+gethostaddr(Host, Family) ->
+    case inet:getaddr(Host, Family) of
+        {ok, IPAddress} -> [{IPAddress, Family}];
+        {error, Reason} -> host_lookup_error(Host, Reason)
+    end.
+
+host_lookup_error(Host, Reason) ->
+    error_logger:error_msg("invalid host ~p - ~p~n", [Host, Reason]),
+    throw({error, {invalid_host, Host, Reason}}).
+
+resolve_family({_,_,_,_},         auto) -> inet;
+resolve_family({_,_,_,_,_,_,_,_}, auto) -> inet6;
+resolve_family(IP,                auto) -> throw({error, {strange_family, IP}});
+resolve_family(_,                 F)    -> F.
+
 %%--------------------------------------------------------------------
 
 %% There are three kinds of machine (for our purposes).
@@ -429,16 +441,19 @@ ipv6_status(TestPort) ->
                         {ok, LSock4}            -> gen_tcp:close(LSock4),
                                                    single_stack;
                         %% IPv6-only machine. Welcome to the future.
-                        {error, eafnosupport}   -> ipv6_only;
+                        {error, eafnosupport}   -> ipv6_only; %% Linux
+                        {error, eprotonosupport}-> ipv6_only; %% FreeBSD
                         %% Dual stack machine with something already
                         %% on IPv4.
                         {error, _}              -> ipv6_status(TestPort + 1)
                     end
             end;
-        {error, eafnosupport} ->
-            %% IPv4-only machine. Welcome to the 90s.
+        %% IPv4-only machine. Welcome to the 90s.
+        {error, eafnosupport} -> %% Linux
+            ipv4_only;
+        {error, eprotonosupport} -> %% FreeBSD
             ipv4_only;
+        %% Port in use
         {error, _} ->
-            %% Port in use
             ipv6_status(TestPort + 1)
     end.
diff --git a/src/rabbit_node_monitor.erl b/src/rabbit_node_monitor.erl
index 8aa24ab5..323cf0ce 100644
--- a/src/rabbit_node_monitor.erl
+++ b/src/rabbit_node_monitor.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_node_monitor).
@@ -55,29 +55,32 @@ notify_cluster() ->
         {_, Bad} -> rabbit_log:info("failed to contact nodes ~p~n", [Bad])
     end,
     %% register other active rabbits with this rabbit
-    [ rabbit_node_monitor:rabbit_running_on(N) || N <- Nodes ],
+    [ rabbit_running_on(N) || N <- Nodes ],
     ok.
 
 %%--------------------------------------------------------------------
 
 init([]) ->
-    {ok, no_state}.
+    {ok, ordsets:new()}.
 
 handle_call(_Request, _From, State) ->
     {noreply, State}.
 
-handle_cast({rabbit_running_on, Node}, State) ->
-    rabbit_log:info("rabbit on ~p up~n", [Node]),
-    erlang:monitor(process, {rabbit, Node}),
-    ok = handle_live_rabbit(Node),
-    {noreply, State};
+handle_cast({rabbit_running_on, Node}, Nodes) ->
+    case ordsets:is_element(Node, Nodes) of
+        true  -> {noreply, Nodes};
+        false -> rabbit_log:info("rabbit on node ~p up~n", [Node]),
+                 erlang:monitor(process, {rabbit, Node}),
+                 ok = handle_live_rabbit(Node),
+                 {noreply, ordsets:add_element(Node, Nodes)}
+    end;
 handle_cast(_Msg, State) ->
     {noreply, State}.
 
-handle_info({'DOWN', _MRef, process, {rabbit, Node}, _Reason}, State) ->
-    rabbit_log:info("node ~p lost 'rabbit'~n", [Node]),
+handle_info({'DOWN', _MRef, process, {rabbit, Node}, _Reason}, Nodes) ->
+    rabbit_log:info("rabbit on node ~p down~n", [Node]),
     ok = handle_dead_rabbit(Node),
-    {noreply, State};
+    {noreply, ordsets:del_element(Node, Nodes)};
 handle_info(_Info, State) ->
     {noreply, State}.
 
diff --git a/src/rabbit_nodes.erl b/src/rabbit_nodes.erl
new file mode 100644
index 00000000..1c23632d
--- /dev/null
+++ b/src/rabbit_nodes.erl
@@ -0,0 +1,100 @@
+%% The contents of this file are subject to the Mozilla Public License
+%% Version 1.1 (the "License"); you may not use this file except in
+%% compliance with the License. You may obtain a copy of the License
+%% at http://www.mozilla.org/MPL/
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and
+%% limitations under the License.
+%%
+%% The Original Code is RabbitMQ.
+%%
+%% The Initial Developer of the Original Code is VMware, Inc.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
+%%
+
+-module(rabbit_nodes).
+
+-export([names/1, diagnostics/1, make/1, parts/1, cookie_hash/0, is_running/2]).
+
+-define(EPMD_TIMEOUT, 30000).
+
+%%----------------------------------------------------------------------------
+%% Specs
+%%----------------------------------------------------------------------------
+
+-ifdef(use_specs).
+
+-spec(names/1 :: (string()) -> rabbit_types:ok_or_error2(
+                                 [{string(), integer()}], term())).
+-spec(diagnostics/1 :: ([node()]) -> string()).
+-spec(make/1 :: ({string(), string()} | string()) -> node()).
+-spec(parts/1 :: (node() | string()) -> {string(), string()}).
+-spec(cookie_hash/0 :: () -> string()).
+-spec(is_running/2 :: (node(), atom()) -> boolean()).
+
+-endif.
+
+%%----------------------------------------------------------------------------
+
+names(Hostname) ->
+    Self = self(),
+    Ref = make_ref(),
+    {Pid, MRef} = spawn_monitor(
+                    fun () -> Self ! {Ref, net_adm:names(Hostname)} end),
+    timer:exit_after(?EPMD_TIMEOUT, Pid, timeout),
+    receive
+        {Ref, Names}                         -> erlang:demonitor(MRef, [flush]),
+                                                Names;
+        {'DOWN', MRef, process, Pid, Reason} -> {error, Reason}
+    end.
+
+diagnostics(Nodes) ->
+    Hosts = lists:usort([element(2, parts(Node)) || Node <- Nodes]),
+    NodeDiags = [{"~nDIAGNOSTICS~n===========~n~n"
+                  "nodes in question: ~p~n~n"
+                  "hosts, their running nodes and ports:", [Nodes]}] ++
+        [diagnostics_host(Host) || Host <- Hosts] ++
+        diagnostics0(),
+    rabbit_misc:format_many(lists:flatten(NodeDiags)).
+
+diagnostics0() ->
+    [{"~ncurrent node details:~n- node name: ~w", [node()]},
+     case init:get_argument(home) of
+         {ok, [[Home]]} -> {"- home dir: ~s", [Home]};
+         Other          -> {"- no home dir: ~p", [Other]}
+     end,
+     {"- cookie hash: ~s", [cookie_hash()]}].
+
+diagnostics_host(Host) ->
+    case names(Host) of
+        {error, EpmdReason} ->
+            {"- unable to connect to epmd on ~s: ~w",
+             [Host, EpmdReason]};
+        {ok, NamePorts} ->
+            {"- ~s: ~p",
+             [Host, [{list_to_atom(Name), Port} ||
+                        {Name, Port} <- NamePorts]]}
+    end.
+
+make({Prefix, Suffix}) -> list_to_atom(lists:append([Prefix, "@", Suffix]));
+make(NodeStr)          -> make(parts(NodeStr)).
+
+parts(Node) when is_atom(Node) ->
+    parts(atom_to_list(Node));
+parts(NodeStr) ->
+    case lists:splitwith(fun (E) -> E =/= $@ end, NodeStr) of
+        {Prefix, []}     -> {_, Suffix} = parts(node()),
+                            {Prefix, Suffix};
+        {Prefix, Suffix} -> {Prefix, tl(Suffix)}
+    end.
+
+cookie_hash() ->
+    base64:encode_to_string(erlang:md5(atom_to_list(erlang:get_cookie()))).
+
+is_running(Node, Application) ->
+    case rpc:call(Node, application, which_applications, [infinity]) of
+        {badrpc, _} -> false;
+        Apps        -> proplists:is_defined(Application, Apps)
+    end.
diff --git a/src/rabbit_plugins.erl b/src/rabbit_plugins.erl
index 62c004f7..30c7bb37 100644
--- a/src/rabbit_plugins.erl
+++ b/src/rabbit_plugins.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2011-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_plugins).
@@ -25,6 +25,18 @@
 -define(ENABLED_OPT, "-E").
 -define(ENABLED_ALL_OPT, "-e").
 
+-define(VERBOSE_DEF, {?VERBOSE_OPT, flag}).
+-define(MINIMAL_DEF, {?MINIMAL_OPT, flag}).
+-define(ENABLED_DEF, {?ENABLED_OPT, flag}).
+-define(ENABLED_ALL_DEF, {?ENABLED_ALL_OPT, flag}).
+
+-define(GLOBAL_DEFS, []).
+
+-define(COMMANDS,
+        [{list, [?VERBOSE_DEF, ?MINIMAL_DEF, ?ENABLED_DEF, ?ENABLED_ALL_DEF]},
+         enable,
+         disable]).
+
 %%----------------------------------------------------------------------------
 
 -ifdef(use_specs).
@@ -45,27 +57,36 @@ start() ->
     {ok, [[PluginsFile|_]|_]} =
         init:get_argument(enabled_plugins_file),
     {ok, [[PluginsDir|_]|_]} = init:get_argument(plugins_dist_dir),
-    {[Command0 | Args], Opts} =
-        case rabbit_misc:get_options([{flag, ?VERBOSE_OPT},
-                                      {flag, ?MINIMAL_OPT},
-                                      {flag, ?ENABLED_OPT},
-                                      {flag, ?ENABLED_ALL_OPT}],
-                                     init:get_plain_arguments()) of
-            {[], _Opts}    -> usage();
-            CmdArgsAndOpts -> CmdArgsAndOpts
+    {Command, Opts, Args} =
+        case rabbit_misc:parse_arguments(?COMMANDS, ?GLOBAL_DEFS,
+                                         init:get_plain_arguments())
+        of
+            {ok, Res}  -> Res;
+            no_command -> print_error("could not recognise command", []),
+                          usage()
+        end,
+
+    PrintInvalidCommandError =
+        fun () ->
+                print_error("invalid command '~s'",
+                            [string:join([atom_to_list(Command) | Args], " ")])
         end,
-    Command = list_to_atom(Command0),
 
     case catch action(Command, Args, Opts, PluginsFile, PluginsDir) of
         ok ->
             rabbit_misc:quit(0);
         {'EXIT', {function_clause, [{?MODULE, action, _} | _]}} ->
-            print_error("invalid command '~s'",
-                        [string:join([atom_to_list(Command) | Args], " ")]),
+            PrintInvalidCommandError(),
+            usage();
+        {'EXIT', {function_clause, [{?MODULE, action, _, _} | _]}} ->
+            PrintInvalidCommandError(),
             usage();
         {error, Reason} ->
             print_error("~p", [Reason]),
             rabbit_misc:quit(2);
+        {error_string, Reason} ->
+            print_error("~s", [Reason]),
+            rabbit_misc:quit(2);
         Other ->
             print_error("~p", [Other]),
             rabbit_misc:quit(2)
@@ -90,7 +111,7 @@ action(list, [Pat], Opts, PluginsFile, PluginsDir) ->
 
 action(enable, ToEnable0, _Opts, PluginsFile, PluginsDir) ->
     case ToEnable0 of
-        [] -> throw("Not enough arguments for 'enable'");
+        [] -> throw({error_string, "Not enough arguments for 'enable'"});
         _  -> ok
     end,
     AllPlugins = find_plugins(PluginsDir),
@@ -100,8 +121,9 @@ action(enable, ToEnable0, _Opts, PluginsFile, PluginsDir) ->
     Missing = ToEnable -- plugin_names(AllPlugins),
     case Missing of
         [] -> ok;
-        _  -> throw(fmt_list("The following plugins could not be found:",
-                             Missing))
+        _  -> throw({error_string,
+                     fmt_list("The following plugins could not be found:",
+                              Missing)})
     end,
     NewEnabled = lists:usort(Enabled ++ ToEnable),
     write_enabled_plugins(PluginsFile, NewEnabled),
@@ -116,7 +138,7 @@ action(enable, ToEnable0, _Opts, PluginsFile, PluginsDir) ->
 
 action(disable, ToDisable0, _Opts, PluginsFile, PluginsDir) ->
     case ToDisable0 of
-        [] -> throw("Not enough arguments for 'disable'");
+        [] -> throw({error_string, "Not enough arguments for 'disable'"});
         _  -> ok
     end,
     ToDisable = [list_to_atom(Name) || Name <- ToDisable0],
@@ -231,9 +253,10 @@ format_plugins(Pattern, Opts, PluginsFile, PluginsDir) ->
                  {false, false} -> normal;
                  {true,  false} -> verbose;
                  {false, true}  -> minimal;
-                 {true,  true}  -> throw("Cannot specify -m and -v together")
+                 {true,  true}  -> throw({error_string,
+                                          "Cannot specify -m and -v together"})
              end,
-    OnlyEnabled = proplists:get_bool(?ENABLED_OPT, Opts),
+    OnlyEnabled    = proplists:get_bool(?ENABLED_OPT,     Opts),
     OnlyEnabledAll = proplists:get_bool(?ENABLED_ALL_OPT, Opts),
 
     AvailablePlugins = find_plugins(PluginsDir),
@@ -245,14 +268,10 @@ format_plugins(Pattern, Opts, PluginsFile, PluginsDir) ->
     Plugins = [ Plugin ||
                   Plugin = #plugin{name = Name} <- AvailablePlugins,
                   re:run(atom_to_list(Name), RE, [{capture, none}]) =:= match,
-                  if OnlyEnabled -> lists:member(Name, EnabledExplicitly);
-                     true        -> true
-                  end,
-                  if OnlyEnabledAll ->
-                          lists:member(Name, EnabledImplicitly) or
-                              lists:member(Name, EnabledExplicitly);
-                     true ->
-                          true
+                  if OnlyEnabled    ->  lists:member(Name, EnabledExplicitly);
+                     OnlyEnabledAll -> (lists:member(Name, EnabledExplicitly) or
+                                        lists:member(Name, EnabledImplicitly));
+                     true           -> true
                   end],
     Plugins1 = usort_plugins(Plugins),
     MaxWidth = lists:max([length(atom_to_list(Name)) ||
@@ -289,7 +308,7 @@ print_list(Header, Plugins) ->
 
 fmt_list(Header, Plugins) ->
     lists:flatten(
-      [Header, $\n, [io_lib:format("  ~s~n", [P]) || P <- Plugins], $\n]).
+      [Header, $\n, [io_lib:format("  ~s~n", [P]) || P <- Plugins]]).
 
 usort_plugins(Plugins) ->
     lists:usort(fun plugins_cmp/2, Plugins).
@@ -325,6 +344,9 @@ lookup_plugins(Names, AllPlugins) ->
 read_enabled_plugins(PluginsFile) ->
     case rabbit_file:read_term_file(PluginsFile) of
         {ok, [Plugins]} -> Plugins;
+        {ok, []}        -> [];
+        {ok, [_|_]}     -> throw({error, {malformed_enabled_plugins_file,
+                                          PluginsFile}});
         {error, enoent} -> [];
         {error, Reason} -> throw({error, {cannot_read_enabled_plugins_file,
                                           PluginsFile, Reason}})
@@ -385,4 +407,3 @@ report_change() ->
         _ ->
              ok
     end.
-
diff --git a/src/rabbit_prelaunch.erl b/src/rabbit_prelaunch.erl
index 50444dc4..162d44f1 100644
--- a/src/rabbit_prelaunch.erl
+++ b/src/rabbit_prelaunch.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_prelaunch).
@@ -22,7 +22,6 @@
 
 -define(BaseApps, [rabbit]).
 -define(ERROR_CODE, 1).
--define(EPMD_TIMEOUT, 30000).
 
 %%----------------------------------------------------------------------------
 %% Specs
@@ -244,16 +243,15 @@ duplicate_node_check([]) ->
     %% Ignore running node while installing windows service
     ok;
 duplicate_node_check(NodeStr) ->
-    Node = rabbit_misc:makenode(NodeStr),
-    {NodeName, NodeHost} = rabbit_misc:nodeparts(Node),
-    case names(NodeHost) of
+    Node = rabbit_nodes:make(NodeStr),
+    {NodeName, NodeHost} = rabbit_nodes:parts(Node),
+    case rabbit_nodes:names(NodeHost) of
         {ok, NamePorts}  ->
             case proplists:is_defined(NodeName, NamePorts) of
                 true -> io:format("node with name ~p "
                                   "already running on ~p~n",
                                   [NodeName, NodeHost]),
-                        [io:format(Fmt ++ "~n", Args) ||
-                            {Fmt, Args} <- rabbit_control:diagnostics(Node)],
+                        io:format(rabbit_nodes:diagnostics([Node]) ++ "~n"),
                         terminate(?ERROR_CODE);
                 false -> ok
             end;
@@ -279,15 +277,3 @@ terminate(Status) ->
                       after infinity -> ok
                       end
     end.
-
-names(Hostname) ->
-    Self = self(),
-    process_flag(trap_exit, true),
-    Pid = spawn_link(fun () -> Self ! {names, net_adm:names(Hostname)} end),
-    timer:exit_after(?EPMD_TIMEOUT, Pid, timeout),
-    Res = receive
-              {names, Names}        -> Names;
-              {'EXIT', Pid, Reason} -> {error, Reason}
-          end,
-    process_flag(trap_exit, false),
-    Res.
diff --git a/src/rabbit_queue_collector.erl b/src/rabbit_queue_collector.erl
index 9b45e798..6dad01cc 100644
--- a/src/rabbit_queue_collector.erl
+++ b/src/rabbit_queue_collector.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_queue_collector).
@@ -23,7 +23,7 @@
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
          terminate/2, code_change/3]).
 
--record(state, {queues, delete_from}).
+-record(state, {monitors, delete_from}).
 
 -include("rabbit.hrl").
 
@@ -32,7 +32,7 @@
 -ifdef(use_specs).
 
 -spec(start_link/0 :: () -> rabbit_types:ok_pid_or_error()).
--spec(register/2 :: (pid(), rabbit_types:amqqueue()) -> 'ok').
+-spec(register/2 :: (pid(), pid()) -> 'ok').
 -spec(delete_all/1 :: (pid()) -> 'ok').
 
 -endif.
@@ -51,39 +51,37 @@ delete_all(CollectorPid) ->
 %%----------------------------------------------------------------------------
 
 init([]) ->
-    {ok, #state{queues = dict:new(), delete_from = undefined}}.
+    {ok, #state{monitors = pmon:new(), delete_from = undefined}}.
 
 %%--------------------------------------------------------------------------
 
-handle_call({register, Q}, _From,
-            State = #state{queues = Queues, delete_from = Deleting}) ->
-    MonitorRef = erlang:monitor(process, Q#amqqueue.pid),
+handle_call({register, QPid}, _From,
+            State = #state{monitors = QMons, delete_from = Deleting}) ->
     case Deleting of
         undefined -> ok;
-        _         -> rabbit_amqqueue:delete_immediately(Q)
+        _         -> ok = rabbit_amqqueue:delete_immediately([QPid])
     end,
-    {reply, ok, State#state{queues = dict:store(MonitorRef, Q, Queues)}};
+    {reply, ok, State#state{monitors = pmon:monitor(QPid, QMons)}};
 
-handle_call(delete_all, From, State = #state{queues      = Queues,
+handle_call(delete_all, From, State = #state{monitors    = QMons,
                                              delete_from = undefined}) ->
-    case dict:size(Queues) of
-        0 -> {reply, ok, State#state{delete_from = From}};
-        _ -> [rabbit_amqqueue:delete_immediately(Q)
-              || {_MRef, Q} <- dict:to_list(Queues)],
-             {noreply, State#state{delete_from = From}}
+    case pmon:monitored(QMons) of
+        []    -> {reply, ok, State#state{delete_from = From}};
+        QPids -> ok = rabbit_amqqueue:delete_immediately(QPids),
+                 {noreply, State#state{delete_from = From}}
     end.
 
 handle_cast(Msg, State) ->
     {stop, {unhandled_cast, Msg}, State}.
 
-handle_info({'DOWN', MonitorRef, process, _DownPid, _Reason},
-            State = #state{queues = Queues, delete_from = Deleting}) ->
-    Queues1 = dict:erase(MonitorRef, Queues),
-    case Deleting =/= undefined andalso dict:size(Queues1) =:= 0 of
+handle_info({'DOWN', _MRef, process, DownPid, _Reason},
+            State = #state{monitors = QMons, delete_from = Deleting}) ->
+    QMons1 = pmon:erase(DownPid, QMons),
+    case Deleting =/= undefined andalso pmon:is_empty(QMons1) of
         true  -> gen_server:reply(Deleting, ok);
         false -> ok
     end,
-    {noreply, State#state{queues = Queues1}}.
+    {noreply, State#state{monitors = QMons1}}.
 
 terminate(_Reason, _State) ->
     ok.
diff --git a/src/rabbit_queue_index.erl b/src/rabbit_queue_index.erl
index f03c1d1c..3ef769c7 100644
--- a/src/rabbit_queue_index.erl
+++ b/src/rabbit_queue_index.erl
@@ -11,15 +11,17 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_queue_index).
 
 -export([init/2, shutdown_terms/1, recover/5,
          terminate/2, delete_and_terminate/1,
-         publish/5, deliver/2, ack/2, sync/1, sync/2, flush/1, read/3,
-         next_segment_boundary/1, bounds/1, recover/1]).
+         publish/5, deliver/2, ack/2, sync/1, needs_sync/1, flush/1,
+         read/3, next_segment_boundary/1, bounds/1, recover/1]).
+
+-export([scan/3]).
 
 -export([add_queue_ttl/0]).
 
@@ -207,7 +209,8 @@
                    -> qistate()).
 -spec(deliver/2 :: ([seq_id()], qistate()) -> qistate()).
 -spec(ack/2 :: ([seq_id()], qistate()) -> qistate()).
--spec(sync/2 :: ([seq_id()], qistate()) -> qistate()).
+-spec(sync/1 :: (qistate()) -> qistate()).
+-spec(needs_sync/1 :: (qistate()) -> boolean()).
 -spec(flush/1 :: (qistate()) -> qistate()).
 -spec(read/3 :: (seq_id(), seq_id(), qistate()) ->
                      {[{rabbit_types:msg_id(), seq_id(),
@@ -218,6 +221,12 @@
                        {non_neg_integer(), non_neg_integer(), qistate()}).
 -spec(recover/1 :: ([rabbit_amqqueue:name()]) -> {[[any()]], {walker(A), A}}).
 
+-spec(scan/3 :: (file:filename(),
+                 fun ((seq_id(), rabbit_types:msg_id(),
+                       rabbit_types:message_properties(), boolean(),
+                       ('del' | 'no_del'), ('ack' | 'no_ack'), A) -> A),
+                     A) -> A).
+
 -spec(add_queue_ttl/0 :: () -> 'ok').
 
 -endif.
@@ -283,20 +292,18 @@ deliver(SeqIds, State) ->
 ack(SeqIds, State) ->
     deliver_or_ack(ack, SeqIds, State).
 
-%% This is only called when there are outstanding confirms and the
-%% queue is idle.
-sync(State = #qistate { unsynced_msg_ids = MsgIds }) ->
-    sync_if(not gb_sets:is_empty(MsgIds), State).
-
-sync(SeqIds, State) ->
-    %% The SeqIds here contains the SeqId of every publish and ack to
-    %% be sync'ed. Ideally we should go through these seqids and only
-    %% sync the journal if the pubs or acks appear in the
-    %% journal. However, this would be complex to do, and given that
-    %% the variable queue publishes and acks to the qi, and then
-    %% syncs, all in one operation, there is no possibility of the
-    %% seqids not being in the journal.
-    sync_if([] =/= SeqIds, State).
+%% This is called when there are outstanding confirms or when the
+%% queue is idle and the journal needs syncing (see needs_sync/1).
+sync(State = #qistate { journal_handle = undefined }) ->
+    State;
+sync(State = #qistate { journal_handle = JournalHdl }) ->
+    ok = file_handle_cache:sync(JournalHdl),
+    notify_sync(State).
+
+needs_sync(#qistate { journal_handle = undefined }) ->
+    false;
+needs_sync(#qistate { journal_handle = JournalHdl }) ->
+    file_handle_cache:needs_sync(JournalHdl).
 
 flush(State = #qistate { dirty_count = 0 }) -> State;
 flush(State)                                -> flush_journal(State).
@@ -379,7 +386,10 @@ all_queue_directory_names(Dir) ->
 %%----------------------------------------------------------------------------
 
 blank_state(QueueName) ->
-    Dir = filename:join(queues_dir(), queue_name_to_dir_name(QueueName)),
+    blank_state_dir(
+      filename:join(queues_dir(), queue_name_to_dir_name(QueueName))).
+
+blank_state_dir(Dir) ->
     {ok, MaxJournal} =
         application:get_env(rabbit, queue_index_max_journal_entries),
     #qistate { dir                 = Dir,
@@ -491,7 +501,7 @@ recover_message(false,     _, no_del,  RelSeq, Segment) ->
 
 queue_name_to_dir_name(Name = #resource { kind = queue }) ->
     <<Num:128>> = erlang:md5(term_to_binary(Name)),
-    lists:flatten(io_lib:format("~.36B", [Num])).
+    rabbit_misc:format("~.36B", [Num]).
 
 queues_dir() ->
     filename:join(rabbit_mnesia:dir(), "queues").
@@ -524,19 +534,34 @@ queue_index_walker({next, Gatherer}) when is_pid(Gatherer) ->
     end.
 
 queue_index_walker_reader(QueueName, Gatherer) ->
-    State = #qistate { segments = Segments, dir = Dir } =
-        recover_journal(blank_state(QueueName)),
-    [ok = segment_entries_foldr(
-            fun (_RelSeq, {{MsgId, _MsgProps, true}, _IsDelivered, no_ack},
-                 ok) ->
-                    gatherer:in(Gatherer, {MsgId, 1});
-                (_RelSeq, _Value, Acc) ->
-                    Acc
-            end, ok, segment_find_or_new(Seg, Dir, Segments)) ||
-        Seg <- all_segment_nums(State)],
-    {_SegmentCounts, _State} = terminate(State),
+    State = blank_state(QueueName),
+    ok = scan_segments(
+           fun (_SeqId, MsgId, _MsgProps, true, _IsDelivered, no_ack, ok) ->
+                   gatherer:in(Gatherer, {MsgId, 1});
+               (_SeqId, _MsgId, _MsgProps, _IsPersistent, _IsDelivered,
+                _IsAcked, Acc) ->
+                   Acc
+           end, ok, State),
     ok = gatherer:finish(Gatherer).
 
+scan(Dir, Fun, Acc) ->
+    scan_segments(Fun, Acc, blank_state_dir(Dir)).
+
+scan_segments(Fun, Acc, State) ->
+    State1 = #qistate { segments = Segments, dir = Dir } =
+        recover_journal(State),
+    Result = lists:foldr(
+      fun (Seg, AccN) ->
+              segment_entries_foldr(
+                fun (RelSeq, {{MsgId, MsgProps, IsPersistent},
+                              IsDelivered, IsAcked}, AccM) ->
+                        Fun(reconstruct_seq_id(Seg, RelSeq), MsgId, MsgProps,
+                            IsPersistent, IsDelivered, IsAcked, AccM)
+                end, AccN, segment_find_or_new(Seg, Dir, Segments))
+      end, Acc, all_segment_nums(State1)),
+    {_SegmentCounts, _State} = terminate(State1),
+    Result.
+
 %%----------------------------------------------------------------------------
 %% expiry/binary manipulation
 %%----------------------------------------------------------------------------
@@ -707,14 +732,6 @@ deliver_or_ack(Kind, SeqIds, State) ->
                                             add_to_journal(SeqId, Kind, StateN)
                                     end, State1, SeqIds)).
 
-sync_if(false, State) ->
-    State;
-sync_if(_Bool, State = #qistate { journal_handle = undefined }) ->
-    State;
-sync_if(true, State = #qistate { journal_handle = JournalHdl }) ->
-    ok = file_handle_cache:sync(JournalHdl),
-    notify_sync(State).
-
 notify_sync(State = #qistate { unsynced_msg_ids = UG, on_sync = OnSyncFun }) ->
     OnSyncFun(UG),
     State #qistate { unsynced_msg_ids = gb_sets:new() }.
diff --git a/src/rabbit_reader.erl b/src/rabbit_reader.erl
index 694abd9e..5acf6aca 100644
--- a/src/rabbit_reader.erl
+++ b/src/rabbit_reader.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_reader).
@@ -25,13 +25,11 @@
 
 -export([init/4, mainloop/2]).
 
--export([conserve_memory/2, server_properties/1]).
-
--export([process_channel_frame/5]). %% used by erlang-client
+-export([conserve_resources/2, server_properties/1]).
 
 -define(HANDSHAKE_TIMEOUT, 10).
 -define(NORMAL_TIMEOUT, 3).
--define(CLOSING_TIMEOUT, 1).
+-define(CLOSING_TIMEOUT, 30).
 -define(CHANNEL_TERMINATION_TIMEOUT, 3).
 -define(SILENT_CLOSE_DELAY, 3).
 
@@ -40,13 +38,15 @@
 -record(v1, {parent, sock, connection, callback, recv_len, pending_recv,
              connection_state, queue_collector, heartbeater, stats_timer,
              channel_sup_sup_pid, start_heartbeat_fun, buf, buf_len,
-             auth_mechanism, auth_state}).
+             auth_mechanism, auth_state, conserve_resources,
+             last_blocked_by, last_blocked_at}).
 
 -define(STATISTICS_KEYS, [pid, recv_oct, recv_cnt, send_oct, send_cnt,
-                          send_pend, state, channels]).
+                          send_pend, state, last_blocked_by, last_blocked_age,
+                          channels]).
 
--define(CREATION_EVENT_KEYS, [pid, address, port, peer_address, peer_port, ssl,
-                              peer_cert_subject, peer_cert_issuer,
+-define(CREATION_EVENT_KEYS, [pid, name, address, port, peer_address, peer_port,
+                              ssl, peer_cert_subject, peer_cert_issuer,
                               peer_cert_validity, auth_mechanism,
                               ssl_protocol, ssl_key_exchange,
                               ssl_cipher, ssl_hash,
@@ -71,7 +71,7 @@
 -spec(info/2 :: (pid(), rabbit_types:info_keys()) -> rabbit_types:infos()).
 -spec(force_event_refresh/1 :: (pid()) -> 'ok').
 -spec(shutdown/2 :: (pid(), string()) -> 'ok').
--spec(conserve_memory/2 :: (pid(), boolean()) -> 'ok').
+-spec(conserve_resources/2 :: (pid(), boolean()) -> 'ok').
 -spec(server_properties/1 :: (rabbit_types:protocol()) ->
                                   rabbit_framing:amqp_table()).
 
@@ -90,10 +90,6 @@
 -spec(system_continue/3 :: (_,_,#v1{}) -> any()).
 -spec(system_terminate/4 :: (_,_,_,_) -> none()).
 
--spec(process_channel_frame/5 ::
-        (rabbit_command_assembler:frame(), pid(), non_neg_integer(), pid(),
-         tuple()) -> tuple()).
-
 -endif.
 
 %%--------------------------------------------------------------------------
@@ -137,8 +133,8 @@ info(Pid, Items) ->
 force_event_refresh(Pid) ->
     gen_server:cast(Pid, force_event_refresh).
 
-conserve_memory(Pid, Conserve) ->
-    Pid ! {conserve_memory, Conserve},
+conserve_resources(Pid, Conserve) ->
+    Pid ! {conserve_resources, Conserve},
     ok.
 
 server_properties(Protocol) ->
@@ -177,25 +173,26 @@ server_capabilities(rabbit_framing_amqp_0_9_1) ->
 server_capabilities(_) ->
     [].
 
+log(Level, Fmt, Args) -> rabbit_log:log(connection, Level, Fmt, Args).
+
 inet_op(F) -> rabbit_misc:throw_on_error(inet_error, F).
 
 socket_op(Sock, Fun) ->
     case Fun(Sock) of
         {ok, Res}       -> Res;
-        {error, Reason} -> rabbit_log:error("error on TCP connection ~p:~p~n",
-                                            [self(), Reason]),
-                           rabbit_log:info("closing TCP connection ~p~n",
-                                           [self()]),
+        {error, Reason} -> log(error, "error on AMQP connection ~p: ~p~n",
+                               [self(), Reason]),
                            exit(normal)
     end.
 
+name(Sock) ->
+    socket_op(Sock, fun (S) -> rabbit_net:connection_string(S, inbound) end).
+
 start_connection(Parent, ChannelSupSupPid, Collector, StartHeartbeatFun, Deb,
                  Sock, SockTransform) ->
     process_flag(trap_exit, true),
-    {PeerAddress, PeerPort} = socket_op(Sock, fun rabbit_net:peername/1),
-    PeerAddressS = rabbit_misc:ntoab(PeerAddress),
-    rabbit_log:info("starting TCP connection ~p from ~s:~p~n",
-                    [self(), PeerAddressS, PeerPort]),
+    ConnStr = name(Sock),
+    log(info, "accepting AMQP connection ~p (~s)~n", [self(), ConnStr]),
     ClientSock = socket_op(Sock, SockTransform),
     erlang:send_after(?HANDSHAKE_TIMEOUT * 1000, self(),
                       handshake_timeout),
@@ -220,27 +217,39 @@ start_connection(Parent, ChannelSupSupPid, Collector, StartHeartbeatFun, Deb,
                 buf                 = [],
                 buf_len             = 0,
                 auth_mechanism      = none,
-                auth_state          = none},
+                auth_state          = none,
+                conserve_resources  = false,
+                last_blocked_by     = none,
+                last_blocked_at     = never},
     try
+        BufSizes = inet_op(fun () ->
+                                   rabbit_net:getopts(
+                                     ClientSock, [sndbuf, recbuf, buffer])
+                           end),
+        BufSz = lists:max([Sz || {_Opt, Sz} <- BufSizes]),
+        ok = inet_op(fun () ->
+                             rabbit_net:setopts(ClientSock, [{buffer, BufSz}])
+                     end),
         recvloop(Deb, switch_callback(rabbit_event:init_stats_timer(
                                        State, #v1.stats_timer),
-                                      handshake, 8))
+                                      handshake, 8)),
+        log(info, "closing AMQP connection ~p (~s)~n", [self(), ConnStr])
     catch
-        Ex -> (if Ex == connection_closed_abruptly ->
-                       fun rabbit_log:warning/2;
-                  true ->
-                       fun rabbit_log:error/2
-               end)("exception on TCP connection ~p from ~s:~p~n~p~n",
-                    [self(), PeerAddressS, PeerPort, Ex])
+        Ex -> log(case Ex of
+                      connection_closed_abruptly -> warning;
+                      _                          -> error
+                  end, "closing AMQP connection ~p (~s):~n~p~n",
+                  [self(), ConnStr, Ex])
     after
-        rabbit_log:info("closing TCP connection ~p from ~s:~p~n",
-                        [self(), PeerAddressS, PeerPort]),
-        %% We don't close the socket explicitly. The reader is the
-        %% controlling process and hence its termination will close
-        %% the socket. Furthermore, gen_tcp:close/1 waits for pending
-        %% output to be sent, which results in unnecessary delays.
+        %% The reader is the controlling process and hence its
+        %% termination will close the socket. Furthermore,
+        %% gen_tcp:close/1 waits for pending output to be sent, which
+        %% results in unnecessary delays. However, to keep the
+        %% file_handle_cache accounting as accurate as possible it
+        %% would be good to close the socket immediately if we
+        %% can. But we can only do this for non-ssl sockets.
         %%
-        %% gen_tcp:close(ClientSock),
+        rabbit_net:maybe_fast_close(ClientSock),
         rabbit_event:notify(connection_closed, [{pid, self()}])
     end,
     done.
@@ -267,21 +276,20 @@ mainloop(Deb, State = #v1{sock = Sock, buf = Buf, buf_len = BufLen}) ->
         {data, Data}    -> recvloop(Deb, State#v1{buf = [Data | Buf],
                                                   buf_len = BufLen + size(Data),
                                                   pending_recv = false});
-        closed          -> if State#v1.connection_state =:= closed ->
-                                   State;
-                              true ->
-                                   throw(connection_closed_abruptly)
+        closed          -> case State#v1.connection_state of
+                               closed -> State;
+                               _      -> throw(connection_closed_abruptly)
                            end;
         {error, Reason} -> throw({inet_error, Reason});
         {other, Other}  -> handle_other(Other, Deb, State)
     end.
 
-handle_other({conserve_memory, Conserve}, Deb, State) ->
-    recvloop(Deb, internal_conserve_memory(Conserve, State));
+handle_other({conserve_resources, Conserve}, Deb, State) ->
+    recvloop(Deb, control_throttle(State#v1{conserve_resources = Conserve}));
 handle_other({channel_closing, ChPid}, Deb, State) ->
     ok = rabbit_channel:ready_for_close(ChPid),
     channel_cleanup(ChPid),
-    mainloop(Deb, maybe_close(State));
+    mainloop(Deb, maybe_close(control_throttle(State)));
 handle_other({'EXIT', Parent, Reason}, _Deb, State = #v1{parent = Parent}) ->
     terminate(io_lib:format("broker forced connection closure "
                             "with reason '~w'", [Reason]), State),
@@ -329,22 +337,25 @@ handle_other({'$gen_call', From, {info, Items}}, Deb, State) ->
                            catch Error -> {error, Error}
                            end),
     mainloop(Deb, State);
-handle_other({'$gen_cast', force_event_refresh}, Deb, State) ->
+handle_other({'$gen_cast', force_event_refresh}, Deb, State)
+  when ?IS_RUNNING(State) ->
     rabbit_event:notify(connection_created,
                         [{type, network} | infos(?CREATION_EVENT_KEYS, State)]),
     mainloop(Deb, State);
+handle_other({'$gen_cast', force_event_refresh}, Deb, State) ->
+    %% Ignore, we will emit a created event once we start running.
+    mainloop(Deb, State);
 handle_other(emit_stats, Deb, State) ->
     mainloop(Deb, emit_stats(State));
 handle_other({system, From, Request}, Deb, State = #v1{parent = Parent}) ->
     sys:handle_system_msg(Request, From, Parent, ?MODULE, Deb, State);
+handle_other({bump_credit, Msg}, Deb, State) ->
+    credit_flow:handle_bump_msg(Msg),
+    recvloop(Deb, control_throttle(State));
 handle_other(Other, _Deb, _State) ->
     %% internal error -> something worth dying for
     exit({unexpected_message, Other}).
 
-switch_callback(State = #v1{connection_state = blocked,
-                            heartbeater = Heartbeater}, Callback, Length) ->
-    ok = rabbit_heartbeat:pause_monitor(Heartbeater),
-    State#v1{callback = Callback, recv_len = Length};
 switch_callback(State, Callback, Length) ->
     State#v1{callback = Callback, recv_len = Length}.
 
@@ -355,17 +366,30 @@ terminate(Explanation, State) when ?IS_RUNNING(State) ->
 terminate(_Explanation, State) ->
     {force, State}.
 
-internal_conserve_memory(true,  State = #v1{connection_state = running}) ->
-    State#v1{connection_state = blocking};
-internal_conserve_memory(false, State = #v1{connection_state = blocking}) ->
-    State#v1{connection_state = running};
-internal_conserve_memory(false, State = #v1{connection_state = blocked,
-                                            heartbeater      = Heartbeater}) ->
-    ok = rabbit_heartbeat:resume_monitor(Heartbeater),
-    State#v1{connection_state = running};
-internal_conserve_memory(_Conserve, State) ->
+control_throttle(State = #v1{connection_state   = CS,
+                             conserve_resources = Mem}) ->
+    case {CS, Mem orelse credit_flow:blocked()} of
+        {running,   true} -> State#v1{connection_state = blocking};
+        {blocking, false} -> State#v1{connection_state = running};
+        {blocked,  false} -> ok = rabbit_heartbeat:resume_monitor(
+                                    State#v1.heartbeater),
+                             State#v1{connection_state = running};
+        {blocked,   true} -> update_last_blocked_by(State);
+        {_,            _} -> State
+    end.
+
+maybe_block(State = #v1{connection_state = blocking}) ->
+    ok = rabbit_heartbeat:pause_monitor(State#v1.heartbeater),
+    update_last_blocked_by(State#v1{connection_state = blocked,
+                                    last_blocked_at  = erlang:now()});
+maybe_block(State) ->
     State.
 
+update_last_blocked_by(State = #v1{conserve_resources = true}) ->
+    State#v1{last_blocked_by = resource};
+update_last_blocked_by(State = #v1{conserve_resources = false}) ->
+    State#v1{last_blocked_by = flow}.
+
 close_connection(State = #v1{queue_collector = Collector,
                              connection = #connection{
                                timeout_sec = TimeoutSec}}) ->
@@ -376,34 +400,30 @@ close_connection(State = #v1{queue_collector = Collector,
     rabbit_queue_collector:delete_all(Collector),
     %% We terminate the connection after the specified interval, but
     %% no later than ?CLOSING_TIMEOUT seconds.
-    TimeoutMillisec =
-        1000 * if TimeoutSec > 0 andalso
-                  TimeoutSec < ?CLOSING_TIMEOUT -> TimeoutSec;
-                  true -> ?CLOSING_TIMEOUT
-               end,
-    erlang:send_after(TimeoutMillisec, self(), terminate_connection),
+    erlang:send_after((if TimeoutSec > 0 andalso
+                          TimeoutSec < ?CLOSING_TIMEOUT -> TimeoutSec;
+                          true                          -> ?CLOSING_TIMEOUT
+                       end) * 1000, self(), terminate_connection),
     State#v1{connection_state = closed}.
 
 handle_dependent_exit(ChPid, Reason, State) ->
-    case termination_kind(Reason) of
-        controlled ->
-            channel_cleanup(ChPid),
-            maybe_close(State);
-        uncontrolled ->
-            case channel_cleanup(ChPid) of
-                undefined -> exit({abnormal_dependent_exit, ChPid, Reason});
-                Channel   -> rabbit_log:error(
-                               "connection ~p, channel ~p - error:~n~p~n",
-                               [self(), Channel, Reason]),
-                             maybe_close(
-                               handle_exception(State, Channel, Reason))
-            end
+    case {channel_cleanup(ChPid), termination_kind(Reason)} of
+        {undefined, uncontrolled} ->
+            exit({abnormal_dependent_exit, ChPid, Reason});
+        {_Channel, controlled} ->
+            maybe_close(control_throttle(State));
+        {Channel, uncontrolled} ->
+            log(error, "AMQP connection ~p, channel ~p - error:~n~p~n",
+                [self(), Channel, Reason]),
+            maybe_close(handle_exception(control_throttle(State),
+                                         Channel, Reason))
     end.
 
 channel_cleanup(ChPid) ->
     case get({ch_pid, ChPid}) of
         undefined       -> undefined;
-        {Channel, MRef} -> erase({channel, Channel}),
+        {Channel, MRef} -> credit_flow:peer_down(ChPid),
+                           erase({channel, Channel}),
                            erase({ch_pid, ChPid}),
                            erlang:demonitor(MRef, [flush]),
                            Channel
@@ -432,19 +452,16 @@ wait_for_channel_termination(0, TimerRef) ->
 wait_for_channel_termination(N, TimerRef) ->
     receive
         {'DOWN', _MRef, process, ChPid, Reason} ->
-            case channel_cleanup(ChPid) of
-                undefined ->
+            case {channel_cleanup(ChPid), termination_kind(Reason)} of
+                {undefined, _} ->
                     exit({abnormal_dependent_exit, ChPid, Reason});
-                Channel ->
-                    case termination_kind(Reason) of
-                        controlled ->
-                            ok;
-                        uncontrolled ->
-                            rabbit_log:error(
-                              "connection ~p, channel ~p - "
-                              "error while terminating:~n~p~n",
-                              [self(), Channel, Reason])
-                    end,
+                {_Channel, controlled} ->
+                    wait_for_channel_termination(N-1, TimerRef);
+                {Channel, uncontrolled} ->
+                    log(error,
+                        "AMQP connection ~p, channel ~p - "
+                        "error while terminating:~n~p~n",
+                        [self(), Channel, Reason]),
                     wait_for_channel_termination(N-1, TimerRef)
             end;
         cancel_wait ->
@@ -493,41 +510,38 @@ handle_frame(Type, Channel, Payload,
     case rabbit_command_assembler:analyze_frame(Type, Payload, Protocol) of
         error         -> throw({unknown_frame, Channel, Type, Payload});
         heartbeat     -> throw({unexpected_heartbeat_frame, Channel});
-        AnalyzedFrame ->
-            case get({channel, Channel}) of
-                {ChPid, FramingState} ->
-                    NewAState = process_channel_frame(
-                                  AnalyzedFrame, self(),
-                                  Channel, ChPid, FramingState),
-                    put({channel, Channel}, {ChPid, NewAState}),
-                    post_process_frame(AnalyzedFrame, ChPid, State);
-                undefined ->
-                    case ?IS_RUNNING(State) of
-                        true  -> send_to_new_channel(
-                                   Channel, AnalyzedFrame, State);
-                        false -> throw({channel_frame_while_starting,
-                                        Channel, State#v1.connection_state,
-                                        AnalyzedFrame})
-                    end
-            end
+        AnalyzedFrame -> process_frame(AnalyzedFrame, Channel, State)
+    end.
+
+process_frame(Frame, Channel, State) ->
+    case get({channel, Channel}) of
+        {ChPid, AState} ->
+            case process_channel_frame(Frame,  ChPid, AState) of
+                {ok, NewAState} -> put({channel, Channel}, {ChPid, NewAState}),
+                                   post_process_frame(Frame, ChPid, State);
+                {error, Reason} -> handle_exception(State, Channel, Reason)
+            end;
+        undefined when ?IS_RUNNING(State) ->
+            ok = create_channel(Channel, State),
+            process_frame(Frame, Channel, State);
+        undefined ->
+            throw({channel_frame_while_starting,
+                   Channel, State#v1.connection_state, Frame})
     end.
 
 post_process_frame({method, 'channel.close_ok', _}, ChPid, State) ->
     channel_cleanup(ChPid),
-    State;
+    control_throttle(State);
 post_process_frame({method, MethodName, _}, _ChPid,
                    State = #v1{connection = #connection{
                                  protocol = Protocol}}) ->
     case Protocol:method_has_content(MethodName) of
         true  -> erlang:bump_reductions(2000),
-                 case State#v1.connection_state of
-                     blocking -> State#v1{connection_state = blocked};
-                     _        -> State
-                 end;
-        false -> State
+                 maybe_block(control_throttle(State));
+        false -> control_throttle(State)
     end;
 post_process_frame(_Frame, _ChPid, State) ->
-    State.
+    control_throttle(State).
 
 handle_input(frame_header, <<Type:8,Channel:16,PayloadSize:32>>, State) ->
     ensure_stats_timer(
@@ -695,10 +709,11 @@ handle_method0(#'connection.open'{virtual_host = VHostPath},
     ok = rabbit_access_control:check_vhost_access(User, VHostPath),
     NewConnection = Connection#connection{vhost = VHostPath},
     ok = send_on_channel0(Sock, #'connection.open_ok'{}, Protocol),
-    State1 = internal_conserve_memory(
-               rabbit_alarm:register(self(), {?MODULE, conserve_memory, []}),
-               State#v1{connection_state = running,
-                        connection = NewConnection}),
+    Conserve = rabbit_alarm:register(self(), {?MODULE, conserve_resources, []}),
+    State1 = control_throttle(
+               State#v1{connection_state   = running,
+                        connection         = NewConnection,
+                        conserve_resources = Conserve}),
     rabbit_event:notify(connection_created,
                         [{type, network} |
                          infos(?CREATION_EVENT_KEYS, State1)]),
@@ -797,6 +812,8 @@ infos(Items, State) -> [{Item, i(Item, State)} || Item <- Items].
 
 i(pid, #v1{}) ->
     self();
+i(name, #v1{sock = Sock}) ->
+    list_to_binary(name(Sock));
 i(address, #v1{sock = Sock}) ->
     socket_info(fun rabbit_net:sockname/1, fun ({A, _}) -> A end, Sock);
 i(port, #v1{sock = Sock}) ->
@@ -830,6 +847,12 @@ i(SockStat, #v1{sock = Sock}) when SockStat =:= recv_oct;
                 fun ([{_, I}]) -> I end);
 i(state, #v1{connection_state = S}) ->
     S;
+i(last_blocked_by, #v1{last_blocked_by = By}) ->
+    By;
+i(last_blocked_age, #v1{last_blocked_at = never}) ->
+    infinity;
+i(last_blocked_age, #v1{last_blocked_at = T}) ->
+    timer:now_diff(erlang:now(), T) / 1000000;
 i(channels, #v1{}) ->
     length(all_channels());
 i(protocol, #v1{connection = #connection{protocol = none}}) ->
@@ -885,7 +908,7 @@ cert_info(F, Sock) ->
 
 %%--------------------------------------------------------------------------
 
-send_to_new_channel(Channel, AnalyzedFrame, State) ->
+create_channel(Channel, State) ->
     #v1{sock = Sock, queue_collector = Collector,
         channel_sup_sup_pid = ChanSupSup,
         connection = #connection{protocol     = Protocol,
@@ -895,26 +918,22 @@ send_to_new_channel(Channel, AnalyzedFrame, State) ->
                                  capabilities = Capabilities}} = State,
     {ok, _ChSupPid, {ChPid, AState}} =
         rabbit_channel_sup_sup:start_channel(
-          ChanSupSup, {tcp, Sock, Channel, FrameMax, self(), Protocol, User,
-                       VHost, Capabilities, Collector}),
+          ChanSupSup, {tcp, Sock, Channel, FrameMax, self(), name(Sock),
+                       Protocol, User, VHost, Capabilities, Collector}),
     MRef = erlang:monitor(process, ChPid),
-    NewAState = process_channel_frame(AnalyzedFrame, self(),
-                                      Channel, ChPid, AState),
-    put({channel, Channel}, {ChPid, NewAState}),
     put({ch_pid, ChPid}, {Channel, MRef}),
-    State.
+    put({channel, Channel}, {ChPid, AState}),
+    ok.
 
-process_channel_frame(Frame, ErrPid, Channel, ChPid, AState) ->
+process_channel_frame(Frame, ChPid, AState) ->
     case rabbit_command_assembler:process(Frame, AState) of
-        {ok, NewAState}                  -> NewAState;
+        {ok, NewAState}                  -> {ok, NewAState};
         {ok, Method, NewAState}          -> rabbit_channel:do(ChPid, Method),
-                                            NewAState;
-        {ok, Method, Content, NewAState} -> rabbit_channel:do(ChPid,
-                                                              Method, Content),
-                                            NewAState;
-        {error, Reason}                  -> ErrPid ! {channel_exit, Channel,
-                                                      Reason},
-                                            AState
+                                            {ok, NewAState};
+        {ok, Method, Content, NewAState} -> rabbit_channel:do_flow(
+                                              ChPid, Method, Content),
+                                            {ok, NewAState};
+        {error, Reason}                  -> {error, Reason}
     end.
 
 handle_exception(State = #v1{connection_state = closed}, _Channel, _Reason) ->
diff --git a/src/rabbit_registry.erl b/src/rabbit_registry.erl
index 9821ae7b..637835c3 100644
--- a/src/rabbit_registry.erl
+++ b/src/rabbit_registry.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_registry).
@@ -23,7 +23,8 @@
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2,
          code_change/3]).
 
--export([register/3, binary_to_type/1, lookup_module/2, lookup_all/1]).
+-export([register/3, unregister/2,
+         binary_to_type/1, lookup_module/2, lookup_all/1]).
 
 -define(SERVER, ?MODULE).
 -define(ETS_NAME, ?MODULE).
@@ -32,6 +33,7 @@
 
 -spec(start_link/0 :: () -> rabbit_types:ok_pid_or_error()).
 -spec(register/3 :: (atom(), binary(), atom()) -> 'ok').
+-spec(unregister/2 :: (atom(), binary()) -> 'ok').
 -spec(binary_to_type/1 ::
         (binary()) -> atom() | rabbit_types:error('not_found')).
 -spec(lookup_module/2 ::
@@ -50,6 +52,9 @@ start_link() ->
 register(Class, TypeName, ModuleName) ->
     gen_server:call(?SERVER, {register, Class, TypeName, ModuleName}, infinity).
 
+unregister(Class, TypeName) ->
+    gen_server:call(?SERVER, {unregister, Class, TypeName}, infinity).
+
 %% This is used with user-supplied arguments (e.g., on exchange
 %% declare), so we restrict it to existing atoms only.  This means it
 %% can throw a badarg, indicating that the type cannot have been
@@ -83,6 +88,10 @@ internal_register(Class, TypeName, ModuleName)
                       {{Class, internal_binary_to_type(TypeName)}, ModuleName}),
     ok.
 
+internal_unregister(Class, TypeName) ->
+    true = ets:delete(?ETS_NAME, {Class, internal_binary_to_type(TypeName)}),
+    ok.
+
 sanity_check_module(ClassModule, Module) ->
     case catch lists:member(ClassModule,
                             lists:flatten(
@@ -95,8 +104,9 @@ sanity_check_module(ClassModule, Module) ->
         true                  -> ok
     end.
 
-class_module(exchange)       -> rabbit_exchange_type;
-class_module(auth_mechanism) -> rabbit_auth_mechanism.
+class_module(exchange)          -> rabbit_exchange_type;
+class_module(auth_mechanism)    -> rabbit_auth_mechanism;
+class_module(runtime_parameter) -> rabbit_runtime_parameter.
 
 %%---------------------------------------------------------------------------
 
@@ -108,6 +118,10 @@ handle_call({register, Class, TypeName, ModuleName}, _From, State) ->
     ok = internal_register(Class, TypeName, ModuleName),
     {reply, ok, State};
 
+handle_call({unregister, Class, TypeName}, _From, State) ->
+    ok = internal_unregister(Class, TypeName),
+    {reply, ok, State};
+
 handle_call(Request, _From, State) ->
     {stop, {unhandled_call, Request}, State}.
 
diff --git a/src/rabbit_restartable_sup.erl b/src/rabbit_restartable_sup.erl
index cda3ccbe..237ab78c 100644
--- a/src/rabbit_restartable_sup.erl
+++ b/src/rabbit_restartable_sup.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_restartable_sup).
@@ -28,7 +28,8 @@
 
 -ifdef(use_specs).
 
--spec(start_link/2 :: (atom(), mfa()) -> rabbit_types:ok_pid_or_error()).
+-spec(start_link/2 :: (atom(), rabbit_types:mfargs()) ->
+                           rabbit_types:ok_pid_or_error()).
 
 -endif.
 
diff --git a/src/rabbit_router.erl b/src/rabbit_router.erl
index 31f5ad14..f4bbda0f 100644
--- a/src/rabbit_router.erl
+++ b/src/rabbit_router.erl
@@ -11,28 +11,24 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_router).
 -include_lib("stdlib/include/qlc.hrl").
 -include("rabbit.hrl").
 
--export([deliver/2, match_bindings/2, match_routing_key/2]).
+-export([match_bindings/2, match_routing_key/2]).
 
 %%----------------------------------------------------------------------------
 
 -ifdef(use_specs).
 
--export_type([routing_key/0, routing_result/0, match_result/0]).
+-export_type([routing_key/0, match_result/0]).
 
 -type(routing_key() :: binary()).
--type(routing_result() :: 'routed' | 'unroutable' | 'not_delivered').
--type(qpids() :: [pid()]).
 -type(match_result() :: [rabbit_types:binding_destination()]).
 
--spec(deliver/2 :: ([rabbit_amqqueue:name()], rabbit_types:delivery()) ->
-                        {routing_result(), qpids()}).
 -spec(match_bindings/2 :: (rabbit_types:binding_source(),
                            fun ((rabbit_types:binding()) -> boolean())) ->
     match_result()).
@@ -44,38 +40,6 @@
 
 %%----------------------------------------------------------------------------
 
-deliver([], #delivery{mandatory = false,
-                      immediate = false}) ->
-    %% /dev/null optimisation
-    {routed, []};
-
-deliver(QNames, Delivery = #delivery{mandatory = false,
-                                     immediate = false}) ->
-    %% optimisation: when Mandatory = false and Immediate = false,
-    %% rabbit_amqqueue:deliver will deliver the message to the queue
-    %% process asynchronously, and return true, which means all the
-    %% QPids will always be returned. It is therefore safe to use a
-    %% fire-and-forget cast here and return the QPids - the semantics
-    %% is preserved. This scales much better than the non-immediate
-    %% case below.
-    QPids = lookup_qpids(QNames),
-    delegate:invoke_no_result(
-      QPids, fun (Pid) -> rabbit_amqqueue:deliver(Pid, Delivery) end),
-    {routed, QPids};
-
-deliver(QNames, Delivery = #delivery{mandatory = Mandatory,
-                                     immediate = Immediate}) ->
-    QPids = lookup_qpids(QNames),
-    {Success, _} =
-        delegate:invoke(QPids,
-                        fun (Pid) ->
-                                rabbit_amqqueue:deliver(Pid, Delivery)
-                        end),
-    {Routed, Handled} =
-        lists:foldl(fun fold_deliveries/2, {false, []}, Success),
-    check_delivery(Mandatory, Immediate, {Routed, Handled}).
-
-
 %% TODO: Maybe this should be handled by a cursor instead.
 %% TODO: This causes a full scan for each entry with the same source
 match_bindings(SrcName, Match) ->
@@ -104,26 +68,6 @@ match_routing_key(SrcName, [_|_] = RoutingKeys) ->
 
 %%--------------------------------------------------------------------
 
-fold_deliveries({Pid, true},{_, Handled}) -> {true, [Pid|Handled]};
-fold_deliveries({_,  false},{_, Handled}) -> {true, Handled}.
-
-%% check_delivery(Mandatory, Immediate, {WasRouted, QPids})
-check_delivery(true, _   , {false, []}) -> {unroutable, []};
-check_delivery(_   , true, {_    , []}) -> {not_delivered, []};
-check_delivery(_   , _   , {_    , Qs}) -> {routed, Qs}.
-
-%% Normally we'd call mnesia:dirty_read/1 here, but that is quite
-%% expensive for the reasons explained in rabbit_misc:dirty_read/1.
-lookup_qpids(QNames) ->
-    lists:foldl(fun (QName, QPids) ->
-                        case ets:lookup(rabbit_queue, QName) of
-                            [#amqqueue{pid = QPid, slave_pids = SPids}] ->
-                                [QPid | SPids ++ QPids];
-                            [] ->
-                                QPids
-                        end
-                end, [], QNames).
-
 %% Normally we'd call mnesia:dirty_select/2 here, but that is quite
 %% expensive for the same reasons as above, and, additionally, due to
 %% mnesia 'fixing' the table with ets:safe_fixtable/2, which is wholly
diff --git a/src/rabbit_runtime_parameter.erl b/src/rabbit_runtime_parameter.erl
new file mode 100644
index 00000000..c7d30116
--- /dev/null
+++ b/src/rabbit_runtime_parameter.erl
@@ -0,0 +1,43 @@
+%% The contents of this file are subject to the Mozilla Public License
+%% Version 1.1 (the "License"); you may not use this file except in
+%% compliance with the License. You may obtain a copy of the License
+%% at http://www.mozilla.org/MPL/
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and
+%% limitations under the License.
+%%
+%% The Original Code is RabbitMQ.
+%%
+%% The Initial Developer of the Original Code is VMware, Inc.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
+%%
+
+-module(rabbit_runtime_parameter).
+
+-ifdef(use_specs).
+
+-type(validate_results() ::
+        'ok' | {error, string(), [term()]} | [validate_results()]).
+
+-callback validate(binary(), binary(), term()) -> validate_results().
+-callback validate_clear(binary(), binary()) -> validate_results().
+-callback notify(binary(), binary(), term()) -> 'ok'.
+-callback notify_clear(binary(), binary()) -> 'ok'.
+
+-else.
+
+-export([behaviour_info/1]).
+
+behaviour_info(callbacks) ->
+    [
+     {validate, 3},
+     {validate_clear, 2},
+     {notify, 3},
+     {notify_clear, 2}
+    ];
+behaviour_info(_Other) ->
+    undefined.
+
+-endif.
diff --git a/src/rabbit_runtime_parameters.erl b/src/rabbit_runtime_parameters.erl
new file mode 100644
index 00000000..172cee92
--- /dev/null
+++ b/src/rabbit_runtime_parameters.erl
@@ -0,0 +1,239 @@
+%% The contents of this file are subject to the Mozilla Public License
+%% Version 1.1 (the "License"); you may not use this file except in
+%% compliance with the License. You may obtain a copy of the License
+%% at http://www.mozilla.org/MPL/
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and
+%% limitations under the License.
+%%
+%% The Original Code is RabbitMQ.
+%%
+%% The Initial Developer of the Original Code is VMware, Inc.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
+%%
+
+-module(rabbit_runtime_parameters).
+
+-include("rabbit.hrl").
+
+-export([parse_set/3, set/3, clear/2, list/0, list/1, list_formatted/0,
+         lookup/2, value/2, value/3, info_keys/0]).
+
+%%----------------------------------------------------------------------------
+
+-ifdef(use_specs).
+
+-type(ok_or_error_string() :: 'ok' | {'error_string', string()}).
+
+-spec(parse_set/3 :: (binary(), binary(), string()) -> ok_or_error_string()).
+-spec(set/3 :: (binary(), binary(), term()) -> ok_or_error_string()).
+-spec(clear/2 :: (binary(), binary()) -> ok_or_error_string()).
+-spec(list/0 :: () -> [rabbit_types:infos()]).
+-spec(list/1 :: (binary()) -> [rabbit_types:infos()] | 'not_found').
+-spec(list_formatted/0 :: () -> [rabbit_types:infos()]).
+-spec(lookup/2 :: (binary(), binary()) -> rabbit_types:infos()).
+-spec(value/2 :: (binary(), binary()) -> term()).
+-spec(value/3 :: (binary(), binary(), term()) -> term()).
+-spec(info_keys/0 :: () -> rabbit_types:info_keys()).
+
+-endif.
+
+%%---------------------------------------------------------------------------
+
+-import(rabbit_misc, [pget/2, pset/3]).
+
+-define(TABLE, rabbit_runtime_parameters).
+
+%%---------------------------------------------------------------------------
+
+parse_set(Component, Key, String) ->
+    case parse(String) of
+        {ok, Term}  -> set(Component, Key, Term);
+        {errors, L} -> format_error(L)
+    end.
+
+set(Component, Key, Term) ->
+    case set0(Component, Key, Term) of
+        ok          -> ok;
+        {errors, L} -> format_error(L)
+    end.
+
+format_error(L) ->
+    {error_string, rabbit_misc:format_many([{"Validation failed~n", []} | L])}.
+
+set0(Component, Key, Term) ->
+    case lookup_component(Component) of
+        {ok, Mod} ->
+            case flatten_errors(validate(Term)) of
+                ok ->
+                    case flatten_errors(Mod:validate(Component, Key, Term)) of
+                        ok ->
+                            case mnesia_update(Component, Key, Term) of
+                                {old, Term} -> ok;
+                                _           -> Mod:notify(Component, Key, Term)
+                            end,
+                            ok;
+                        E ->
+                            E
+                    end;
+                E ->
+                    E
+            end;
+        E ->
+            E
+    end.
+
+mnesia_update(Component, Key, Term) ->
+    rabbit_misc:execute_mnesia_transaction(
+      fun () ->
+              Res = case mnesia:read(?TABLE, {Component, Key}, read) of
+                        []       -> new;
+                        [Params] -> {old, Params#runtime_parameters.value}
+                    end,
+              ok = mnesia:write(?TABLE, c(Component, Key, Term), write),
+              Res
+      end).
+
+clear(Component, Key) ->
+    case clear0(Component, Key) of
+        ok          -> ok;
+        {errors, L} -> format_error(L)
+    end.
+
+clear0(Component, Key) ->
+    case lookup_component(Component) of
+        {ok, Mod} -> case flatten_errors(Mod:validate_clear(Component, Key)) of
+                         ok -> mnesia_clear(Component, Key),
+                               Mod:notify_clear(Component, Key),
+                               ok;
+                         E  -> E
+                     end;
+        E         -> E
+    end.
+
+mnesia_clear(Component, Key) ->
+    ok = rabbit_misc:execute_mnesia_transaction(
+           fun () ->
+                   ok = mnesia:delete(?TABLE, {Component, Key}, write)
+           end).
+
+list() ->
+    [p(P) || P <- rabbit_misc:dirty_read_all(?TABLE)].
+
+list(Component) ->
+    case lookup_component(Component) of
+        {ok, _} -> Match = #runtime_parameters{key = {Component, '_'}, _ = '_'},
+                   [p(P) || P <- mnesia:dirty_match_object(?TABLE, Match)];
+        _       -> not_found
+    end.
+
+list_formatted() ->
+    [pset(value, format(pget(value, P)), P) || P <- list()].
+
+lookup(Component, Key) ->
+    case lookup0(Component, Key, rabbit_misc:const(not_found)) of
+        not_found -> not_found;
+        Params    -> p(Params)
+    end.
+
+value(Component, Key) ->
+    case lookup0(Component, Key, rabbit_misc:const(not_found)) of
+        not_found -> not_found;
+        Params    -> Params#runtime_parameters.value
+    end.
+
+value(Component, Key, Default) ->
+    Params = lookup0(Component, Key,
+                     fun () -> lookup_missing(Component, Key, Default) end),
+    Params#runtime_parameters.value.
+
+lookup0(Component, Key, DefaultFun) ->
+    case mnesia:dirty_read(?TABLE, {Component, Key}) of
+        []  -> DefaultFun();
+        [R] -> R
+    end.
+
+lookup_missing(Component, Key, Default) ->
+    rabbit_misc:execute_mnesia_transaction(
+      fun () ->
+              case mnesia:read(?TABLE, {Component, Key}, read) of
+                  []  -> Record = c(Component, Key, Default),
+                         mnesia:write(?TABLE, Record, write),
+                         Record;
+                  [R] -> R
+              end
+      end).
+
+c(Component, Key, Default) -> #runtime_parameters{key = {Component, Key},
+                                                  value = Default}.
+
+p(#runtime_parameters{key = {Component, Key}, value = Value}) ->
+    [{component, Component},
+     {key,       Key},
+     {value,     Value}].
+
+info_keys() -> [component, key, value].
+
+%%---------------------------------------------------------------------------
+
+lookup_component(Component) ->
+    case rabbit_registry:lookup_module(
+           runtime_parameter, list_to_atom(binary_to_list(Component))) of
+        {error, not_found} -> {errors,
+                               [{"component ~s not found", [Component]}]};
+        {ok, Module}       -> {ok, Module}
+    end.
+
+parse(Src0) ->
+    Src1 = string:strip(Src0),
+    Src = case lists:reverse(Src1) of
+              [$. |_] -> Src1;
+              _       -> Src1 ++ "."
+          end,
+    case erl_scan:string(Src) of
+        {ok, Scanned, _} ->
+            case erl_parse:parse_term(Scanned) of
+                {ok, Parsed} ->
+                    {ok, Parsed};
+                {error, E} ->
+                    {errors,
+                     [{"Could not parse value: ~s", [format_parse_error(E)]}]}
+            end;
+        {error, E, _} ->
+            {errors, [{"Could not scan value: ~s", [format_parse_error(E)]}]}
+    end.
+
+format_parse_error({_Line, Mod, Err}) ->
+    lists:flatten(Mod:format_error(Err)).
+
+format(Term) ->
+    list_to_binary(rabbit_misc:format("~p", [Term])).
+
+%%---------------------------------------------------------------------------
+
+%% We will want to be able to biject these to JSON. So we have some
+%% generic restrictions on what we consider acceptable.
+validate(Proplist = [T | _]) when is_tuple(T) -> validate_proplist(Proplist);
+validate(L) when is_list(L)                   -> validate_list(L);
+validate(T) when is_tuple(T)                  -> {error, "tuple: ~p", [T]};
+validate(B) when is_boolean(B)                -> ok;
+validate(null)                                -> ok;
+validate(A) when is_atom(A)                   -> {error, "atom: ~p", [A]};
+validate(N) when is_number(N)                 -> ok;
+validate(B) when is_binary(B)                 -> ok;
+validate(B) when is_bitstring(B)              -> {error, "bitstring: ~p", [B]}.
+
+validate_list(L) -> [validate(I) || I <- L].
+validate_proplist(L) -> [vp(I) || I <- L].
+
+vp({K, V}) when is_binary(K) -> validate(V);
+vp({K, _V})                  -> {error, "bad key: ~p", [K]};
+vp(H)                        -> {error, "not two tuple: ~p", [H]}.
+
+flatten_errors(L) ->
+    case [{F, A} || I <- lists:flatten([L]), {error, F, A} <- [I]] of
+        [] -> ok;
+        E  -> {errors, E}
+    end.
diff --git a/src/rabbit_runtime_parameters_test.erl b/src/rabbit_runtime_parameters_test.erl
new file mode 100644
index 00000000..f23b3227
--- /dev/null
+++ b/src/rabbit_runtime_parameters_test.erl
@@ -0,0 +1,38 @@
+%% The contents of this file are subject to the Mozilla Public License
+%% Version 1.1 (the "License"); you may not use this file except in
+%% compliance with the License. You may obtain a copy of the License
+%% at http://www.mozilla.org/MPL/
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and
+%% limitations under the License.
+%%
+%% The Original Code is RabbitMQ.
+%%
+%% The Initial Developer of the Original Code is VMware, Inc.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
+%%
+
+-module(rabbit_runtime_parameters_test).
+-behaviour(rabbit_runtime_parameter).
+
+-export([validate/3, validate_clear/2, notify/3, notify_clear/2]).
+-export([register/0, unregister/0]).
+
+register() ->
+    rabbit_registry:register(runtime_parameter, <<"test">>, ?MODULE).
+
+unregister() ->
+    rabbit_registry:unregister(runtime_parameter, <<"test">>).
+
+validate(<<"test">>, <<"good">>,  _Term)      -> ok;
+validate(<<"test">>, <<"maybe">>, <<"good">>) -> ok;
+validate(<<"test">>, _, _)                    -> {error, "meh", []}.
+
+validate_clear(<<"test">>, <<"good">>)  -> ok;
+validate_clear(<<"test">>, <<"maybe">>) -> ok;
+validate_clear(<<"test">>, _)           -> {error, "meh", []}.
+
+notify(_, _, _) -> ok.
+notify_clear(_, _) -> ok.
diff --git a/src/rabbit_sasl_report_file_h.erl b/src/rabbit_sasl_report_file_h.erl
index 963294d9..e8beecfe 100644
--- a/src/rabbit_sasl_report_file_h.erl
+++ b/src/rabbit_sasl_report_file_h.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_sasl_report_file_h).
diff --git a/src/rabbit_ssl.erl b/src/rabbit_ssl.erl
index e0defa9e..22ff555f 100644
--- a/src/rabbit_ssl.erl
+++ b/src/rabbit_ssl.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_ssl).
@@ -21,7 +21,7 @@
 -include_lib("public_key/include/public_key.hrl").
 
 -export([peer_cert_issuer/1, peer_cert_subject/1, peer_cert_validity/1]).
--export([peer_cert_subject_item/2]).
+-export([peer_cert_subject_items/2, peer_cert_auth_name/1]).
 
 %%--------------------------------------------------------------------------
 
@@ -34,8 +34,10 @@
 -spec(peer_cert_issuer/1        :: (certificate()) -> string()).
 -spec(peer_cert_subject/1       :: (certificate()) -> string()).
 -spec(peer_cert_validity/1      :: (certificate()) -> string()).
--spec(peer_cert_subject_item/2  ::
-        (certificate(), tuple()) -> string() | 'not_found').
+-spec(peer_cert_subject_items/2  ::
+        (certificate(), tuple()) -> [string()] | 'not_found').
+-spec(peer_cert_auth_name/1 ::
+        (certificate()) -> binary() | 'not_found' | 'unsafe').
 
 -endif.
 
@@ -59,8 +61,8 @@ peer_cert_subject(Cert) ->
                       format_rdn_sequence(Subject)
               end, Cert).
 
-%% Return a part of the certificate's subject.
-peer_cert_subject_item(Cert, Type) ->
+%% Return the parts of the certificate's subject.
+peer_cert_subject_items(Cert, Type) ->
     cert_info(fun(#'OTPCertificate' {
                      tbsCertificate = #'OTPTBSCertificate' {
                        subject = Subject }}) ->
@@ -72,11 +74,47 @@ peer_cert_validity(Cert) ->
     cert_info(fun(#'OTPCertificate' {
                      tbsCertificate = #'OTPTBSCertificate' {
                        validity = {'Validity', Start, End} }}) ->
-                      lists:flatten(
-                        io_lib:format("~s - ~s", [format_asn1_value(Start),
-                                                  format_asn1_value(End)]))
+                      rabbit_misc:format("~s - ~s", [format_asn1_value(Start),
+                                                     format_asn1_value(End)])
               end, Cert).
 
+%% Extract a username from the certificate
+peer_cert_auth_name(Cert) ->
+    {ok, Mode} = application:get_env(rabbit, ssl_cert_login_from),
+    peer_cert_auth_name(Mode, Cert).
+
+peer_cert_auth_name(distinguished_name, Cert) ->
+    case auth_config_sane() of
+        true  -> iolist_to_binary(peer_cert_subject(Cert));
+        false -> unsafe
+    end;
+
+peer_cert_auth_name(common_name, Cert) ->
+    %% If there is more than one CN then we join them with "," in a
+    %% vaguely DN-like way. But this is more just so we do something
+    %% more intelligent than crashing, if you actually want to escape
+    %% things properly etc, use DN mode.
+    case auth_config_sane() of
+        true  -> case peer_cert_subject_items(Cert, ?'id-at-commonName') of
+                     not_found -> not_found;
+                     CNs       -> list_to_binary(string:join(CNs, ","))
+                 end;
+        false -> unsafe
+    end.
+
+auth_config_sane() ->
+    {ok, Opts} = application:get_env(rabbit, ssl_options),
+    case {proplists:get_value(fail_if_no_peer_cert, Opts),
+          proplists:get_value(verify, Opts)} of
+        {true, verify_peer} ->
+            true;
+        {F, V} ->
+            rabbit_log:warning("SSL certificate authentication disabled, "
+                               "fail_if_no_peer_cert=~p; "
+                               "verify=~p~n", [F, V]),
+            false
+    end.
+
 %%--------------------------------------------------------------------------
 
 cert_info(F, Cert) ->
@@ -89,8 +127,8 @@ find_by_type(Type, {rdnSequence, RDNs}) ->
     case [V || #'AttributeTypeAndValue'{type = T, value = V}
                    <- lists:flatten(RDNs),
                T == Type] of
-        [Val] -> format_asn1_value(Val);
-        []    -> not_found
+        [] -> not_found;
+        L  -> [format_asn1_value(V) || V <- L]
     end.
 
 %%--------------------------------------------------------------------------
@@ -150,11 +188,12 @@ escape_rdn_value([$ ], middle) ->
 escape_rdn_value([C | S], middle) when C =:= $"; C =:= $+; C =:= $,; C =:= $;;
                                        C =:= $<; C =:= $>; C =:= $\\ ->
     [$\\, C | escape_rdn_value(S, middle)];
-escape_rdn_value([C | S], middle) when C < 32 ; C =:= 127 ->
-    %% only U+0000 needs escaping, but for display purposes it's handy
-    %% to escape all non-printable chars
-    lists:flatten(io_lib:format("\\~2.16.0B", [C])) ++
-        escape_rdn_value(S, middle);
+escape_rdn_value([C | S], middle) when C < 32 ; C >= 126 ->
+    %% Of ASCII characters only U+0000 needs escaping, but for display
+    %% purposes it's handy to escape all non-printable chars. All non-ASCII
+    %% characters get converted to UTF-8 sequences and then escaped. We've
+    %% already got a UTF-8 sequence here, so just escape it.
+    rabbit_misc:format("\\~2.16.0B", [C]) ++ escape_rdn_value(S, middle);
 escape_rdn_value([C | S], middle) ->
     [C | escape_rdn_value(S, middle)].
 
@@ -167,6 +206,10 @@ format_asn1_value({utcTime, [Y1, Y2, M1, M2, D1, D2, H1, H2,
                              Min1, Min2, S1, S2, $Z]}) ->
     io_lib:format("20~c~c-~c~c-~c~cT~c~c:~c~c:~c~cZ",
                   [Y1, Y2, M1, M2, D1, D2, H1, H2, Min1, Min2, S1, S2]);
+%% We appear to get an untagged value back for an ia5string
+%% (e.g. domainComponent).
+format_asn1_value(V) when is_list(V) ->
+    V;
 format_asn1_value(V) ->
     io_lib:format("~p", [V]).
 
diff --git a/src/rabbit_sup.erl b/src/rabbit_sup.erl
index 802ea5e2..f142d233 100644
--- a/src/rabbit_sup.erl
+++ b/src/rabbit_sup.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_sup).
@@ -19,6 +19,8 @@
 -behaviour(supervisor).
 
 -export([start_link/0, start_child/1, start_child/2, start_child/3,
+         start_supervisor_child/1, start_supervisor_child/2,
+         start_supervisor_child/3,
          start_restartable_child/1, start_restartable_child/2, stop_child/1]).
 
 -export([init/1]).
@@ -33,7 +35,11 @@
 
 -spec(start_link/0 :: () -> rabbit_types:ok_pid_or_error()).
 -spec(start_child/1 :: (atom()) -> 'ok').
+-spec(start_child/2 :: (atom(), [any()]) -> 'ok').
 -spec(start_child/3 :: (atom(), atom(), [any()]) -> 'ok').
+-spec(start_supervisor_child/1 :: (atom()) -> 'ok').
+-spec(start_supervisor_child/2 :: (atom(), [any()]) -> 'ok').
+-spec(start_supervisor_child/3 :: (atom(), atom(), [any()]) -> 'ok').
 -spec(start_restartable_child/1 :: (atom()) -> 'ok').
 -spec(start_restartable_child/2 :: (atom(), [any()]) -> 'ok').
 -spec(stop_child/1 :: (atom()) -> rabbit_types:ok_or_error(any())).
@@ -42,32 +48,37 @@
 
 %%----------------------------------------------------------------------------
 
-start_link() ->
-    supervisor:start_link({local, ?SERVER}, ?MODULE, []).
+start_link() -> supervisor:start_link({local, ?SERVER}, ?MODULE, []).
 
-start_child(Mod) ->
-    start_child(Mod, []).
+start_child(Mod) -> start_child(Mod, []).
 
-start_child(Mod, Args) ->
-    start_child(Mod, Mod, Args).
+start_child(Mod, Args) -> start_child(Mod, Mod, Args).
 
 start_child(ChildId, Mod, Args) ->
-    {ok, _} = supervisor:start_child(?SERVER,
-                                     {ChildId, {Mod, start_link, Args},
-                                      transient, ?MAX_WAIT, worker, [Mod]}),
-    ok.
+    child_reply(supervisor:start_child(
+                  ?SERVER,
+                  {ChildId, {Mod, start_link, Args},
+                   transient, ?MAX_WAIT, worker, [Mod]})).
 
-start_restartable_child(Mod) ->
-    start_restartable_child(Mod, []).
+start_supervisor_child(Mod) -> start_supervisor_child(Mod, []).
+
+start_supervisor_child(Mod, Args) -> start_supervisor_child(Mod, Mod, Args).
+
+start_supervisor_child(ChildId, Mod, Args) ->
+    child_reply(supervisor:start_child(
+                  ?SERVER,
+                  {ChildId, {Mod, start_link, Args},
+                   transient, infinity, supervisor, [Mod]})).
+
+start_restartable_child(Mod) -> start_restartable_child(Mod, []).
 
 start_restartable_child(Mod, Args) ->
     Name = list_to_atom(atom_to_list(Mod) ++ "_sup"),
-    {ok, _} = supervisor:start_child(
-                ?SERVER,
-                {Name, {rabbit_restartable_sup, start_link,
-                        [Name, {Mod, start_link, Args}]},
-                 transient, infinity, supervisor, [rabbit_restartable_sup]}),
-    ok.
+    child_reply(supervisor:start_child(
+                  ?SERVER,
+                  {Name, {rabbit_restartable_sup, start_link,
+                          [Name, {Mod, start_link, Args}]},
+                   transient, infinity, supervisor, [rabbit_restartable_sup]})).
 
 stop_child(ChildId) ->
     case supervisor:terminate_child(?SERVER, ChildId) of
@@ -75,5 +86,10 @@ stop_child(ChildId) ->
         E  -> E
     end.
 
-init([]) ->
-    {ok, {{one_for_all, 0, 1}, []}}.
+init([]) -> {ok, {{one_for_all, 0, 1}, []}}.
+
+
+%%----------------------------------------------------------------------------
+
+child_reply({ok, _}) -> ok;
+child_reply(X)       -> X.
diff --git a/src/rabbit_tests.erl b/src/rabbit_tests.erl
index 00d46f5a..bae4928d 100644
--- a/src/rabbit_tests.erl
+++ b/src/rabbit_tests.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_tests).
@@ -35,6 +35,7 @@ all_tests() ->
     passed = mirrored_supervisor_tests:all_tests(),
     application:set_env(rabbit, file_handles_high_watermark, 10, infinity),
     ok = file_handle_cache:set_limit(10),
+    passed = test_multi_call(),
     passed = test_file_handle_cache(),
     passed = test_backing_queue(),
     passed = test_priority_queue(),
@@ -49,9 +50,10 @@ all_tests() ->
     passed = test_app_management(),
     passed = test_log_management_during_startup(),
     passed = test_statistics(),
-    passed = test_option_parser(),
+    passed = test_arguments_parser(),
     passed = test_cluster_management(),
     passed = test_user_management(),
+    passed = test_runtime_parameters(),
     passed = test_server_status(),
     passed = test_confirms(),
     passed = maybe_run_cluster_dependent_tests(),
@@ -59,7 +61,7 @@ all_tests() ->
     passed.
 
 maybe_run_cluster_dependent_tests() ->
-    SecondaryNode = rabbit_misc:makenode("hare"),
+    SecondaryNode = rabbit_nodes:make("hare"),
 
     case net_adm:ping(SecondaryNode) of
         pong -> passed = run_cluster_dependent_tests(SecondaryNode);
@@ -71,10 +73,13 @@ maybe_run_cluster_dependent_tests() ->
 run_cluster_dependent_tests(SecondaryNode) ->
     SecondaryNodeS = atom_to_list(SecondaryNode),
 
+    cover:stop(SecondaryNode),
     ok = control_action(stop_app, []),
     ok = control_action(reset, []),
     ok = control_action(cluster, [SecondaryNodeS]),
     ok = control_action(start_app, []),
+    cover:start(SecondaryNode),
+    ok = control_action(start_app, SecondaryNode, [], []),
 
     io:format("Running cluster dependent tests with node ~p~n", [SecondaryNode]),
     passed = test_delegates_async(SecondaryNode),
@@ -104,6 +109,26 @@ run_cluster_dependent_tests(SecondaryNode) ->
 
     passed.
 
+test_multi_call() ->
+    Fun = fun() ->
+                  receive
+                      {'$gen_call', {From, Mref}, request} ->
+                          From ! {Mref, response}
+                  end,
+                  receive
+                      never -> ok
+                  end
+          end,
+    Pid1 = spawn(Fun),
+    Pid2 = spawn(Fun),
+    Pid3 = spawn(Fun),
+    exit(Pid2, bang),
+    {[{Pid1, response}, {Pid3, response}], [{Pid2, _Fail}]} =
+        rabbit_misc:multi_call([Pid1, Pid2, Pid3], request),
+    exit(Pid1, bang),
+    exit(Pid3, bang),
+    passed.
+
 test_priority_queue() ->
 
     false = priority_queue:is_queue(not_a_queue),
@@ -776,27 +801,57 @@ test_log_management_during_startup() ->
     ok = control_action(start_app, []),
     passed.
 
-test_option_parser() ->
-    %% command and arguments should just pass through
-    ok = check_get_options({["mock_command", "arg1", "arg2"], []},
-                           [], ["mock_command", "arg1", "arg2"]),
-
-    %% get flags
-    ok = check_get_options(
-           {["mock_command", "arg1"], [{"-f", true}, {"-f2", false}]},
-           [{flag, "-f"}, {flag, "-f2"}], ["mock_command", "arg1", "-f"]),
+test_arguments_parser() ->
+    GlobalOpts1 = [{"-f1", flag}, {"-o1", {option, "foo"}}],
+    Commands1 = [command1, {command2, [{"-f2", flag}, {"-o2", {option, "bar"}}]}],
 
-    %% get options
-    ok = check_get_options(
-           {["mock_command"], [{"-foo", "bar"}, {"-baz", "notbaz"}]},
-           [{option, "-foo", "notfoo"}, {option, "-baz", "notbaz"}],
-           ["mock_command", "-foo", "bar"]),
+    GetOptions =
+        fun (Args) ->
+                rabbit_misc:parse_arguments(Commands1, GlobalOpts1, Args)
+        end,
 
-    %% shuffled and interleaved arguments and options
-    ok = check_get_options(
-           {["a1", "a2", "a3"], [{"-o1", "hello"}, {"-o2", "noto2"}, {"-f", true}]},
-           [{option, "-o1", "noto1"}, {flag, "-f"}, {option, "-o2", "noto2"}],
-           ["-f", "a1", "-o1", "hello", "a2", "a3"]),
+    check_parse_arguments(no_command, GetOptions, []),
+    check_parse_arguments(no_command, GetOptions, ["foo", "bar"]),
+    check_parse_arguments(
+      {ok, {command1, [{"-f1", false}, {"-o1", "foo"}], []}},
+      GetOptions, ["command1"]),
+    check_parse_arguments(
+      {ok, {command1, [{"-f1", false}, {"-o1", "blah"}], []}},
+      GetOptions, ["command1", "-o1", "blah"]),
+    check_parse_arguments(
+      {ok, {command1, [{"-f1", true}, {"-o1", "foo"}], []}},
+      GetOptions, ["command1", "-f1"]),
+    check_parse_arguments(
+      {ok, {command1, [{"-f1", false}, {"-o1", "blah"}], []}},
+      GetOptions, ["-o1", "blah", "command1"]),
+    check_parse_arguments(
+      {ok, {command1, [{"-f1", false}, {"-o1", "blah"}], ["quux"]}},
+      GetOptions, ["-o1", "blah", "command1", "quux"]),
+    check_parse_arguments(
+      {ok, {command1, [{"-f1", true}, {"-o1", "blah"}], ["quux", "baz"]}},
+      GetOptions, ["command1", "quux", "-f1", "-o1", "blah", "baz"]),
+    %% For duplicate flags, the last one counts
+    check_parse_arguments(
+      {ok, {command1, [{"-f1", false}, {"-o1", "second"}], []}},
+      GetOptions, ["-o1", "first", "command1", "-o1", "second"]),
+    %% If the flag "eats" the command, the command won't be recognised
+    check_parse_arguments(no_command, GetOptions,
+                      ["-o1", "command1", "quux"]),
+    %% If a flag eats another flag, the eaten flag won't be recognised
+    check_parse_arguments(
+      {ok, {command1, [{"-f1", false}, {"-o1", "-f1"}], []}},
+      GetOptions, ["command1", "-o1", "-f1"]),
+
+    %% Now for some command-specific flags...
+    check_parse_arguments(
+      {ok, {command2, [{"-f1", false}, {"-f2", false},
+                       {"-o1", "foo"}, {"-o2", "bar"}], []}},
+      GetOptions, ["command2"]),
+
+    check_parse_arguments(
+      {ok, {command2, [{"-f1", false}, {"-f2", true},
+                       {"-o1", "baz"}, {"-o2", "bar"}], ["quux", "foo"]}},
+      GetOptions, ["-f2", "command2", "quux", "-o1", "baz", "foo"]),
 
     passed.
 
@@ -859,7 +914,9 @@ test_cluster_management() ->
                                         "invalid2@invalid"]),
     ok = assert_ram_node(),
 
-    SecondaryNode = rabbit_misc:makenode("hare"),
+    ok = control_action(reset, []),
+
+    SecondaryNode = rabbit_nodes:make("hare"),
     case net_adm:ping(SecondaryNode) of
         pong -> passed = test_cluster_management2(SecondaryNode);
         pang -> io:format("Skipping clustering tests with node ~p~n",
@@ -874,7 +931,6 @@ test_cluster_management2(SecondaryNode) ->
     SecondaryNodeS = atom_to_list(SecondaryNode),
 
     %% make a disk node
-    ok = control_action(reset, []),
     ok = control_action(cluster, [NodeS]),
     ok = assert_disc_node(),
     %% make a ram node
@@ -889,6 +945,14 @@ test_cluster_management2(SecondaryNode) ->
     ok = control_action(stop_app, []),
     ok = assert_ram_node(),
 
+    %% ram node will not start by itself
+    ok = control_action(stop_app, []),
+    ok = control_action(stop_app, SecondaryNode, [], []),
+    {error, _} = control_action(start_app, []),
+    ok = control_action(start_app, SecondaryNode, [], []),
+    ok = control_action(start_app, []),
+    ok = control_action(stop_app, []),
+
     %% change cluster config while remaining in same cluster
     ok = control_action(force_cluster, ["invalid2@invalid", SecondaryNodeS]),
     ok = control_action(start_app, []),
@@ -897,8 +961,7 @@ test_cluster_management2(SecondaryNode) ->
     %% join non-existing cluster as a ram node
     ok = control_action(force_cluster, ["invalid1@invalid",
                                         "invalid2@invalid"]),
-    ok = control_action(start_app, []),
-    ok = control_action(stop_app, []),
+    {error, _} = control_action(start_app, []),
     ok = assert_ram_node(),
 
     %% join empty cluster as a ram node (converts to disc)
@@ -953,7 +1016,9 @@ test_cluster_management2(SecondaryNode) ->
     ok = control_action(cluster, [SecondaryNodeS, NodeS]),
     ok = control_action(start_app, []),
     ok = control_action(stop_app, []),
+    cover:stop(SecondaryNode),
     ok = control_action(reset, []),
+    cover:start(SecondaryNode),
 
     %% attempt to leave cluster when no other node is alive
     ok = control_action(cluster, [SecondaryNodeS, NodeS]),
@@ -970,7 +1035,15 @@ test_cluster_management2(SecondaryNode) ->
     %% leave system clustered, with the secondary node as a ram node
     ok = control_action(force_reset, []),
     ok = control_action(start_app, []),
-    ok = control_action(force_reset, SecondaryNode, [], []),
+    %% Yes, this is rather ugly. But since we're a clustered Mnesia
+    %% node and we're telling another clustered node to reset itself,
+    %% we will get disconnected half way through causing a
+    %% badrpc. This never happens in real life since rabbitmqctl is
+    %% not a clustered Mnesia node.
+    cover:stop(SecondaryNode),
+    {badrpc, nodedown} = control_action(force_reset, SecondaryNode, [], []),
+    pong = net_adm:ping(SecondaryNode),
+    cover:start(SecondaryNode),
     ok = control_action(cluster, SecondaryNode, [NodeS], []),
     ok = control_action(start_app, SecondaryNode, [], []),
 
@@ -1055,11 +1128,43 @@ test_user_management() ->
 
     passed.
 
+test_runtime_parameters() ->
+    rabbit_runtime_parameters_test:register(),
+    Good = fun(L) -> ok                = control_action(set_parameter, L) end,
+    Bad  = fun(L) -> {error_string, _} = control_action(set_parameter, L) end,
+
+    %% Acceptable for bijection
+    Good(["test", "good", "<<\"ignore\">>"]),
+    Good(["test", "good", "123"]),
+    Good(["test", "good", "true"]),
+    Good(["test", "good", "false"]),
+    Good(["test", "good", "null"]),
+    Good(["test", "good", "[{<<\"key\">>, <<\"value\">>}]"]),
+
+    %% Various forms of fail due to non-bijectability
+    Bad(["test", "good", "atom"]),
+    Bad(["test", "good", "{tuple, foo}"]),
+    Bad(["test", "good", "[{<<\"key\">>, <<\"value\">>, 1}]"]),
+    Bad(["test", "good", "[{key, <<\"value\">>}]"]),
+
+    %% Test actual validation hook
+    Good(["test", "maybe", "<<\"good\">>"]),
+    Bad(["test", "maybe", "<<\"bad\">>"]),
+
+    ok = control_action(list_parameters, []),
+
+    ok = control_action(clear_parameter, ["test", "good"]),
+    ok = control_action(clear_parameter, ["test", "maybe"]),
+    {error_string, _} =
+        control_action(clear_parameter, ["test", "neverexisted"]),
+    rabbit_runtime_parameters_test:unregister(),
+    passed.
+
 test_server_status() ->
     %% create a few things so there is some useful information to list
     Writer = spawn(fun () -> receive shutdown -> ok end end),
     {ok, Ch} = rabbit_channel:start_link(
-                 1, self(), Writer, self(), rabbit_framing_amqp_0_9_1,
+                 1, self(), Writer, self(), "", rabbit_framing_amqp_0_9_1,
                  user(<<"user">>), <<"/">>, [], self(),
                  rabbit_limiter:make_token(self())),
     [Q, Q2] = [Queue || Name <- [<<"foo">>, <<"bar">>],
@@ -1130,7 +1235,7 @@ test_spawn() ->
     Me = self(),
     Writer = spawn(fun () -> test_writer(Me) end),
     {ok, Ch} = rabbit_channel:start_link(
-                 1, Me, Writer, Me, rabbit_framing_amqp_0_9_1,
+                 1, Me, Writer, Me, "", rabbit_framing_amqp_0_9_1,
                  user(<<"guest">>), <<"/">>, [], Me,
                   rabbit_limiter:make_token(self())),
     ok = rabbit_channel:do(Ch, #'channel.open'{}),
@@ -1203,6 +1308,9 @@ test_confirms() ->
                                           },
                       rabbit_basic:build_content(
                         #'P_basic'{delivery_mode = 2}, <<"">>)),
+    %% We must not kill the queue before the channel has processed the
+    %% 'publish'.
+    ok = rabbit_channel:flush(Ch),
     %% Crash the queue
     QPid1 ! boom,
     %% Wait for a nack
@@ -1527,10 +1635,13 @@ expand_options(As, Bs) ->
                         end
                 end, Bs, As).
 
-check_get_options({ExpArgs, ExpOpts}, Defs, Args) ->
-    {ExpArgs, ResOpts} = rabbit_misc:get_options(Defs, Args),
-    true = lists:sort(ExpOpts) == lists:sort(ResOpts), % don't care about the order
-    ok.
+check_parse_arguments(ExpRes, Fun, As) ->
+    SortRes =
+        fun (no_command)          -> no_command;
+            ({ok, {C, KVs, As1}}) -> {ok, {C, lists:sort(KVs), As1}}
+        end,
+
+    true = SortRes(ExpRes) =:= SortRes(Fun(As)).
 
 empty_files(Files) ->
     [case file:read_file_info(File) of
@@ -1779,10 +1890,10 @@ test_msg_store() ->
     restart_msg_store_empty(),
     MsgIds = [msg_id_bin(M) || M <- lists:seq(1,100)],
     {MsgIds1stHalf, MsgIds2ndHalf} = lists:split(length(MsgIds) div 2, MsgIds),
-    Ref = rabbit_guid:guid(),
+    Ref = rabbit_guid:gen(),
     {Cap, MSCState} = msg_store_client_init_capture(
                         ?PERSISTENT_MSG_STORE, Ref),
-    Ref2 = rabbit_guid:guid(),
+    Ref2 = rabbit_guid:gen(),
     {Cap2, MSC2State} = msg_store_client_init_capture(
                           ?PERSISTENT_MSG_STORE, Ref2),
     %% check we don't contain any of the msgs we're about to publish
@@ -1934,7 +2045,7 @@ test_msg_store_confirms(MsgIds, Cap, MSCState) ->
     passed.
 
 test_msg_store_confirm_timer() ->
-    Ref = rabbit_guid:guid(),
+    Ref = rabbit_guid:gen(),
     MsgId  = msg_id_bin(1),
     Self = self(),
     MSCState = rabbit_msg_store:client_init(
@@ -1963,7 +2074,7 @@ msg_store_keep_busy_until_confirm(MsgIds, MSCState) ->
 test_msg_store_client_delete_and_terminate() ->
     restart_msg_store_empty(),
     MsgIds = [msg_id_bin(M) || M <- lists:seq(1, 10)],
-    Ref = rabbit_guid:guid(),
+    Ref = rabbit_guid:gen(),
     MSCState = msg_store_client_init(?PERSISTENT_MSG_STORE, Ref),
     ok = msg_store_write(MsgIds, MSCState),
     %% test the 'dying client' fast path for writes
@@ -1979,7 +2090,7 @@ test_queue() ->
 init_test_queue() ->
     TestQueue = test_queue(),
     Terms = rabbit_queue_index:shutdown_terms(TestQueue),
-    PRef = proplists:get_value(persistent_ref, Terms, rabbit_guid:guid()),
+    PRef = proplists:get_value(persistent_ref, Terms, rabbit_guid:gen()),
     PersistentClient = msg_store_client_init(?PERSISTENT_MSG_STORE, PRef),
     Res = rabbit_queue_index:recover(
             TestQueue, Terms, false,
@@ -2013,7 +2124,7 @@ restart_app() ->
     rabbit:start().
 
 queue_index_publish(SeqIds, Persistent, Qi) ->
-    Ref = rabbit_guid:guid(),
+    Ref = rabbit_guid:gen(),
     MsgStore = case Persistent of
                    true  -> ?PERSISTENT_MSG_STORE;
                    false -> ?TRANSIENT_MSG_STORE
@@ -2022,7 +2133,7 @@ queue_index_publish(SeqIds, Persistent, Qi) ->
     {A, B = [{_SeqId, LastMsgIdWritten} | _]} =
         lists:foldl(
           fun (SeqId, {QiN, SeqIdsMsgIdsAcc}) ->
-                  MsgId = rabbit_guid:guid(),
+                  MsgId = rabbit_guid:gen(),
                   QiM = rabbit_queue_index:publish(
                           MsgId, SeqId, #message_properties{}, Persistent, QiN),
                   ok = rabbit_msg_store:write(MsgId, MsgId, MSCState),
@@ -2045,7 +2156,7 @@ verify_read_with_published(_Delivered, _Persistent, _Read, _Published) ->
 test_queue_index_props() ->
     with_empty_test_queue(
       fun(Qi0) ->
-              MsgId = rabbit_guid:guid(),
+              MsgId = rabbit_guid:gen(),
               Props = #message_properties{expiry=12345},
               Qi1 = rabbit_queue_index:publish(MsgId, 1, Props, true, Qi0),
               {[{MsgId, 1, Props, _, _}], Qi2} =
@@ -2222,17 +2333,29 @@ test_amqqueue(Durable) ->
         #amqqueue { durable = Durable }.
 
 with_fresh_variable_queue(Fun) ->
-    ok = empty_test_queue(),
-    VQ = variable_queue_init(test_amqqueue(true), false),
-    S0 = rabbit_variable_queue:status(VQ),
-    assert_props(S0, [{q1, 0}, {q2, 0},
-                      {delta, {delta, undefined, 0, undefined}},
-                      {q3, 0}, {q4, 0},
-                      {len, 0}]),
-    _ = rabbit_variable_queue:delete_and_terminate(shutdown, Fun(VQ)),
+    Ref = make_ref(),
+    Me = self(),
+    %% Run in a separate process since rabbit_msg_store will send
+    %% bump_credit messages and we want to ignore them
+    spawn_link(fun() ->
+                       ok = empty_test_queue(),
+                       VQ = variable_queue_init(test_amqqueue(true), false),
+                       S0 = rabbit_variable_queue:status(VQ),
+                       assert_props(S0, [{q1, 0}, {q2, 0},
+                                         {delta,
+                                          {delta, undefined, 0, undefined}},
+                                         {q3, 0}, {q4, 0},
+                                         {len, 0}]),
+                       _ = rabbit_variable_queue:delete_and_terminate(
+                        shutdown, Fun(VQ)),
+                       Me ! Ref
+               end),
+    receive
+        Ref -> ok
+    end,
     passed.
 
-publish_and_confirm(QPid, Payload, Count) ->
+publish_and_confirm(Q, Payload, Count) ->
     Seqs = lists:seq(1, Count),
     [begin
          Msg = rabbit_basic:message(rabbit_misc:r(<<>>, exchange, <<>>),
@@ -2240,7 +2363,7 @@ publish_and_confirm(QPid, Payload, Count) ->
                                     Payload),
          Delivery = #delivery{mandatory = false, immediate = false,
                               sender = self(), message = Msg, msg_seq_no = Seq},
-         true = rabbit_amqqueue:deliver(QPid, Delivery)
+         {routed, _} = rabbit_amqqueue:deliver([Q], Delivery)
      end || Seq <- Seqs],
     wait_for_confirms(gb_sets:from_list(Seqs)).
 
@@ -2249,8 +2372,8 @@ wait_for_confirms(Unconfirmed) ->
         true  -> ok;
         false -> receive {'$gen_cast', {confirm, Confirmed, _}} ->
                          wait_for_confirms(
-                           gb_sets:difference(Unconfirmed,
-                                              gb_sets:from_list(Confirmed)))
+                           rabbit_misc:gb_sets_difference(
+                             Unconfirmed, gb_sets:from_list(Confirmed)))
                  after 5000 -> exit(timeout_waiting_for_confirm)
                  end
     end.
@@ -2331,10 +2454,10 @@ test_dropwhile(VQ0) ->
             fun (N, Props) -> Props#message_properties{expiry = N} end, VQ0),
 
     %% drop the first 5 messages
-    VQ2 = rabbit_variable_queue:dropwhile(
-            fun(#message_properties { expiry = Expiry }) ->
-                    Expiry =< 5
-            end, VQ1),
+    {undefined, VQ2} = rabbit_variable_queue:dropwhile(
+                         fun(#message_properties { expiry = Expiry }) ->
+                                 Expiry =< 5
+                         end, false, VQ1),
 
     %% fetch five now
     VQ3 = lists:foldl(fun (_N, VQN) ->
@@ -2351,10 +2474,13 @@ test_dropwhile(VQ0) ->
 test_dropwhile_varying_ram_duration(VQ0) ->
     VQ1 = variable_queue_publish(false, 1, VQ0),
     VQ2 = rabbit_variable_queue:set_ram_duration_target(0, VQ1),
-    VQ3 = rabbit_variable_queue:dropwhile(fun(_) -> false end, VQ2),
+    {undefined, VQ3} = rabbit_variable_queue:dropwhile(
+                         fun(_) -> false end, false, VQ2),
     VQ4 = rabbit_variable_queue:set_ram_duration_target(infinity, VQ3),
     VQ5 = variable_queue_publish(false, 1, VQ4),
-    rabbit_variable_queue:dropwhile(fun(_) -> false end, VQ5).
+    {undefined, VQ6} =
+        rabbit_variable_queue:dropwhile(fun(_) -> false end, false, VQ5),
+    VQ6.
 
 test_variable_queue_dynamic_duration_change(VQ0) ->
     SegmentSize = rabbit_queue_index:next_segment_boundary(0),
@@ -2477,7 +2603,7 @@ test_queue_recover() ->
     Count = 2 * rabbit_queue_index:next_segment_boundary(0),
     {new, #amqqueue { pid = QPid, name = QName } = Q} =
         rabbit_amqqueue:declare(test_queue(), true, false, [], none),
-    publish_and_confirm(QPid, <<>>, Count),
+    publish_and_confirm(Q, <<>>, Count),
 
     exit(QPid, kill),
     MRef = erlang:monitor(process, QPid),
@@ -2497,7 +2623,7 @@ test_queue_recover() ->
               {{_Msg1, true, _AckTag1, CountMinusOne}, VQ2} =
                   rabbit_variable_queue:fetch(true, VQ1),
               _VQ3 = rabbit_variable_queue:delete_and_terminate(shutdown, VQ2),
-              rabbit_amqqueue:internal_delete(QName)
+              rabbit_amqqueue:internal_delete(QName, QPid1)
       end),
     passed.
 
@@ -2507,7 +2633,7 @@ test_variable_queue_delete_msg_store_files_callback() ->
         rabbit_amqqueue:declare(test_queue(), true, false, [], none),
     Payload = <<0:8388608>>, %% 1MB
     Count = 30,
-    publish_and_confirm(QPid, Payload, Count),
+    publish_and_confirm(Q, Payload, Count),
 
     rabbit_amqqueue:set_ram_duration_target(QPid, 0),
 
diff --git a/src/rabbit_tests_event_receiver.erl b/src/rabbit_tests_event_receiver.erl
index abcbe0b6..72c07b51 100644
--- a/src/rabbit_tests_event_receiver.erl
+++ b/src/rabbit_tests_event_receiver.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_tests_event_receiver).
diff --git a/src/rabbit_trace.erl b/src/rabbit_trace.erl
index 58079ccf..3a5b96de 100644
--- a/src/rabbit_trace.erl
+++ b/src/rabbit_trace.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_trace).
diff --git a/src/rabbit_types.erl b/src/rabbit_types.erl
index 2db960ac..732c29b6 100644
--- a/src/rabbit_types.erl
+++ b/src/rabbit_types.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_types).
@@ -28,12 +28,9 @@
               binding/0, binding_source/0, binding_destination/0,
               amqqueue/0, exchange/0,
               connection/0, protocol/0, user/0, internal_user/0,
-              username/0, password/0, password_hash/0, ok/1, error/1,
-              ok_or_error/1, ok_or_error2/2, ok_pid_or_error/0, channel_exit/0,
-              connection_exit/0]).
-
--type(channel_exit() :: no_return()).
--type(connection_exit() :: no_return()).
+              username/0, password/0, password_hash/0,
+              ok/1, error/1, ok_or_error/1, ok_or_error2/2, ok_pid_or_error/0,
+              channel_exit/0, connection_exit/0, mfargs/0]).
 
 -type(maybe(T) :: T | 'none').
 -type(vhost() :: binary()).
@@ -156,4 +153,9 @@
 -type(ok_or_error2(A, B) :: ok(A) | error(B)).
 -type(ok_pid_or_error() :: ok_or_error2(pid(), any())).
 
+-type(channel_exit() :: no_return()).
+-type(connection_exit() :: no_return()).
+
+-type(mfargs() :: {atom(), atom(), [any()]}).
+
 -endif. % use_specs
diff --git a/src/rabbit_upgrade.erl b/src/rabbit_upgrade.erl
index 717d94a8..e1a7bcae 100644
--- a/src/rabbit_upgrade.erl
+++ b/src/rabbit_upgrade.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_upgrade).
@@ -28,7 +28,9 @@
 -ifdef(use_specs).
 
 -spec(maybe_upgrade_mnesia/0 :: () -> 'ok').
--spec(maybe_upgrade_local/0 :: () -> 'ok' | 'version_not_available').
+-spec(maybe_upgrade_local/0 :: () -> 'ok' |
+                                     'version_not_available' |
+                                     'starting_from_scratch').
 
 -endif.
 
@@ -119,8 +121,13 @@ remove_backup() ->
     info("upgrades: Mnesia backup removed~n", []).
 
 maybe_upgrade_mnesia() ->
-    AllNodes = rabbit_mnesia:all_clustered_nodes(),
+    %% rabbit_mnesia:all_clustered_nodes/0 will return [] at this point
+    %% if we are a RAM node since Mnesia has not started yet.
+    AllNodes = lists:usort(rabbit_mnesia:all_clustered_nodes() ++
+                               rabbit_mnesia:read_cluster_nodes_config()),
     case rabbit_version:upgrades_required(mnesia) of
+        {error, starting_from_scratch} ->
+            ok;
         {error, version_not_available} ->
             case AllNodes of
                 [_] -> ok;
@@ -235,6 +242,7 @@ nodes_running(Nodes) ->
 maybe_upgrade_local() ->
     case rabbit_version:upgrades_required(local) of
         {error, version_not_available} -> version_not_available;
+        {error, starting_from_scratch} -> starting_from_scratch;
         {error, _} = Err               -> throw(Err);
         {ok, []}                       -> ensure_backup_removed(),
                                           ok;
diff --git a/src/rabbit_upgrade_functions.erl b/src/rabbit_upgrade_functions.erl
index e0ca8cbb..485ccc5f 100644
--- a/src/rabbit_upgrade_functions.erl
+++ b/src/rabbit_upgrade_functions.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_upgrade_functions).
@@ -35,6 +35,8 @@
 -rabbit_upgrade({gm,                    mnesia, []}).
 -rabbit_upgrade({exchange_scratch,      mnesia, [trace_exchanges]}).
 -rabbit_upgrade({mirrored_supervisor,   mnesia, []}).
+-rabbit_upgrade({topic_trie_node,       mnesia, []}).
+-rabbit_upgrade({runtime_parameters,    mnesia, []}).
 
 %% -------------------------------------------------------------------
 
@@ -54,6 +56,8 @@
 -spec(gm/0                    :: () -> 'ok').
 -spec(exchange_scratch/0      :: () -> 'ok').
 -spec(mirrored_supervisor/0   :: () -> 'ok').
+-spec(topic_trie_node/0       :: () -> 'ok').
+-spec(runtime_parameters/0    :: () -> 'ok').
 
 -endif.
 
@@ -177,6 +181,18 @@ mirrored_supervisor() ->
            [{record_name, mirrored_sup_childspec},
             {attributes, [key, mirroring_pid, childspec]}]).
 
+topic_trie_node() ->
+    create(rabbit_topic_trie_node,
+           [{record_name, topic_trie_node},
+            {attributes, [trie_node, edge_count, binding_count]},
+            {type, ordered_set}]).
+
+runtime_parameters() ->
+    create(rabbit_runtime_parameters,
+           [{record_name, runtime_parameters},
+            {attributes, [key, value]},
+            {disc_copies, [node()]}]).
+
 %%--------------------------------------------------------------------
 
 transform(TableName, Fun, FieldList) ->
diff --git a/src/rabbit_variable_queue.erl b/src/rabbit_variable_queue.erl
index 63a0927f..dafb3f2e 100644
--- a/src/rabbit_variable_queue.erl
+++ b/src/rabbit_variable_queue.erl
@@ -11,18 +11,17 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_variable_queue).
 
--export([init/3, terminate/2, delete_and_terminate/2,
-         purge/1, publish/4, publish_delivered/5, drain_confirmed/1,
-         dropwhile/2, fetch/2, ack/2, requeue/2, len/1, is_empty/1,
-         set_ram_duration_target/2, ram_duration/1,
-         needs_timeout/1, timeout/1, handle_pre_hibernate/1,
-         status/1, invoke/3, is_duplicate/2, discard/3,
-         multiple_routing_keys/0]).
+-export([init/3, terminate/2, delete_and_terminate/2, purge/1,
+         publish/4, publish_delivered/5, drain_confirmed/1,
+         dropwhile/3, fetch/2, ack/2, requeue/2, len/1, is_empty/1,
+         set_ram_duration_target/2, ram_duration/1, needs_timeout/1,
+         timeout/1, handle_pre_hibernate/1, status/1, invoke/3,
+         is_duplicate/2, discard/3, multiple_routing_keys/0, fold/3]).
 
 -export([start/1, stop/0]).
 
@@ -324,7 +323,6 @@
 
 -type(timestamp() :: {non_neg_integer(), non_neg_integer(), non_neg_integer()}).
 -type(seq_id()  :: non_neg_integer()).
--type(ack()     :: seq_id()).
 
 -type(rates() :: #rates { egress      :: {timestamp(), non_neg_integer()},
                           ingress     :: {timestamp(), non_neg_integer()},
@@ -336,6 +334,13 @@
                           count        :: non_neg_integer(),
                           end_seq_id   :: non_neg_integer() }).
 
+%% The compiler (rightfully) complains that ack() and state() are
+%% unused. For this reason we duplicate a -spec from
+%% rabbit_backing_queue with the only intent being to remove
+%% warnings. The problem here is that we can't parameterise the BQ
+%% behaviour by these two types as we would like to. We still leave
+%% these here for documentation purposes.
+-type(ack() :: seq_id()).
 -type(state() :: #vqstate {
              q1                    :: ?QUEUE:?QUEUE(),
              q2                    :: ?QUEUE:?QUEUE(),
@@ -351,7 +356,7 @@
              durable               :: boolean(),
              transient_threshold   :: non_neg_integer(),
 
-             async_callback        :: async_callback(),
+             async_callback        :: rabbit_backing_queue:async_callback(),
 
              len                   :: non_neg_integer(),
              persistent_count      :: non_neg_integer(),
@@ -369,8 +374,8 @@
              ack_out_counter       :: non_neg_integer(),
              ack_in_counter        :: non_neg_integer(),
              ack_rates             :: rates() }).
-
--include("rabbit_backing_queue_spec.hrl").
+%% Duplicated from rabbit_backing_queue
+-spec(ack/2 :: ([ack()], state()) -> {[rabbit_guid:guid()], state()}).
 
 -spec(multiple_routing_keys/0 :: () -> 'ok').
 
@@ -434,7 +439,7 @@ init(#amqqueue { name = QueueName, durable = true }, true,
     Terms = rabbit_queue_index:shutdown_terms(QueueName),
     {PRef, Terms1} =
         case proplists:get_value(persistent_ref, Terms) of
-            undefined -> {rabbit_guid:guid(), []};
+            undefined -> {rabbit_guid:gen(), []};
             PRef1     -> {PRef1, Terms}
         end,
     PersistentClient = msg_store_client_init(?PERSISTENT_MSG_STORE, PRef,
@@ -581,15 +586,27 @@ drain_confirmed(State = #vqstate { confirmed = C }) ->
                                         confirmed = gb_sets:new() }}
     end.
 
-dropwhile(Pred, State) ->
+dropwhile(Pred, AckRequired, State) -> dropwhile(Pred, AckRequired, State, []).
+
+dropwhile(Pred, AckRequired, State, Msgs) ->
+    End = fun(S) when AckRequired -> {lists:reverse(Msgs), S};
+             (S)                  -> {undefined, S}
+          end,
     case queue_out(State) of
         {empty, State1} ->
-            a(State1);
+            End(a(State1));
         {{value, MsgStatus = #msg_status { msg_props = MsgProps }}, State1} ->
-            case Pred(MsgProps) of
-                true ->  {_, State2} = internal_fetch(false, MsgStatus, State1),
-                         dropwhile(Pred, State2);
-                false -> a(in_r(MsgStatus, State1))
+            case {Pred(MsgProps), AckRequired} of
+                {true, true} ->
+                    {MsgStatus1, State2} = read_msg(MsgStatus, State1),
+                    {{Msg, _, AckTag, _}, State3} =
+                         internal_fetch(true, MsgStatus1, State2),
+                    dropwhile(Pred, AckRequired, State3, [{Msg, AckTag} | Msgs]);
+                {true, false} ->
+                    {_, State2} = internal_fetch(false, MsgStatus, State1),
+                    dropwhile(Pred, AckRequired, State2, undefined);
+                {false, _} ->
+                    End(a(in_r(MsgStatus, State1)))
             end
     end.
 
@@ -628,11 +645,22 @@ ack(AckTags, State) ->
                          persistent_count = PCount1,
                          ack_out_counter  = AckOutCount + length(AckTags) })}.
 
-requeue(AckTags, #vqstate { delta = Delta,
-                                    q3         = Q3,
-                                    q4         = Q4,
-                                    in_counter = InCounter,
-                                    len        = Len } = State) ->
+fold(undefined, State, _AckTags) ->
+    State;
+fold(MsgFun, State = #vqstate{pending_ack = PA}, AckTags) ->
+    lists:foldl(
+      fun(SeqId, State1) ->
+              {MsgStatus, State2} =
+                  read_msg(gb_trees:get(SeqId, PA), State1),
+              MsgFun(MsgStatus#msg_status.msg, SeqId),
+              State2
+      end, State, AckTags).
+
+requeue(AckTags, #vqstate { delta      = Delta,
+                            q3         = Q3,
+                            q4         = Q4,
+                            in_counter = InCounter,
+                            len        = Len } = State) ->
     {SeqIds,  Q4a, MsgIds,  State1} = queue_merge(lists:sort(AckTags), Q4, [],
                                                   beta_limit(Q3),
                                                   fun publish_alpha/2, State),
@@ -731,21 +759,27 @@ ram_duration(State = #vqstate {
                  ram_msg_count_prev = RamMsgCount,
                  ram_ack_count_prev = RamAckCount }}.
 
-needs_timeout(State) ->
-    case needs_index_sync(State) of
-        false -> case reduce_memory_use(
-                        fun (_Quota, State1) -> {0, State1} end,
-                        fun (_Quota, State1) -> State1 end,
-                        fun (_Quota, State1) -> {0, State1} end,
-                        State) of
-                     {true,  _State} -> idle;
-                     {false, _State} -> false
-                 end;
-        true  -> timed
+needs_timeout(State = #vqstate { index_state = IndexState }) ->
+    case must_sync_index(State) of
+        true  -> timed;
+        false ->
+            case rabbit_queue_index:needs_sync(IndexState) of
+                true  -> idle;
+                false -> case reduce_memory_use(
+                                fun (_Quota, State1) -> {0, State1} end,
+                                fun (_Quota, State1) -> State1 end,
+                                fun (_Quota, State1) -> {0, State1} end,
+                                State) of
+                             {true,  _State} -> idle;
+                             {false, _State} -> false
+                         end
+            end
     end.
 
-timeout(State) ->
-    a(reduce_memory_use(confirm_commit_index(State))).
+timeout(State = #vqstate { index_state = IndexState }) ->
+    IndexState1 = rabbit_queue_index:sync(IndexState),
+    State1 = State #vqstate { index_state = IndexState1 },
+    a(reduce_memory_use(State1)).
 
 handle_pre_hibernate(State = #vqstate { index_state = IndexState }) ->
     State #vqstate { index_state = rabbit_queue_index:flush(IndexState) }.
@@ -860,7 +894,8 @@ with_immutable_msg_store_state(MSCState, IsPersistent, Fun) ->
     Res.
 
 msg_store_client_init(MsgStore, MsgOnDiskFun, Callback) ->
-    msg_store_client_init(MsgStore, rabbit_guid:guid(), MsgOnDiskFun, Callback).
+    msg_store_client_init(MsgStore, rabbit_guid:gen(), MsgOnDiskFun,
+                          Callback).
 
 msg_store_client_init(MsgStore, Ref, MsgOnDiskFun, Callback) ->
     CloseFDsFun = msg_store_close_fds_fun(MsgStore =:= ?PERSISTENT_MSG_STORE),
@@ -870,17 +905,23 @@ msg_store_client_init(MsgStore, Ref, MsgOnDiskFun, Callback) ->
 msg_store_write(MSCState, IsPersistent, MsgId, Msg) ->
     with_immutable_msg_store_state(
       MSCState, IsPersistent,
-      fun (MSCState1) -> rabbit_msg_store:write(MsgId, Msg, MSCState1) end).
+      fun (MSCState1) ->
+              rabbit_msg_store:write_flow(MsgId, Msg, MSCState1)
+      end).
 
 msg_store_read(MSCState, IsPersistent, MsgId) ->
     with_msg_store_state(
       MSCState, IsPersistent,
-      fun (MSCState1) -> rabbit_msg_store:read(MsgId, MSCState1) end).
+      fun (MSCState1) ->
+              rabbit_msg_store:read(MsgId, MSCState1)
+      end).
 
 msg_store_remove(MSCState, IsPersistent, MsgIds) ->
     with_immutable_msg_store_state(
       MSCState, IsPersistent,
-      fun (MCSState1) -> rabbit_msg_store:remove(MsgIds, MCSState1) end).
+      fun (MCSState1) ->
+              rabbit_msg_store:remove(MsgIds, MCSState1)
+      end).
 
 msg_store_close_fds(MSCState, IsPersistent) ->
     with_msg_store_state(
@@ -1255,24 +1296,18 @@ find_persistent_count(LensByStore) ->
 %% Internal plumbing for confirms (aka publisher acks)
 %%----------------------------------------------------------------------------
 
-confirm_commit_index(State = #vqstate { index_state = IndexState }) ->
-    case needs_index_sync(State) of
-        true  -> State #vqstate {
-                   index_state = rabbit_queue_index:sync(IndexState) };
-        false -> State
-    end.
-
 record_confirms(MsgIdSet, State = #vqstate { msgs_on_disk        = MOD,
                                              msg_indices_on_disk = MIOD,
                                              unconfirmed         = UC,
                                              confirmed           = C }) ->
-    State #vqstate { msgs_on_disk        = gb_sets:difference(MOD,  MsgIdSet),
-                     msg_indices_on_disk = gb_sets:difference(MIOD, MsgIdSet),
-                     unconfirmed         = gb_sets:difference(UC,   MsgIdSet),
-                     confirmed           = gb_sets:union     (C,    MsgIdSet) }.
-
-needs_index_sync(#vqstate { msg_indices_on_disk = MIOD,
-                            unconfirmed = UC }) ->
+    State #vqstate {
+      msgs_on_disk        = rabbit_misc:gb_sets_difference(MOD,  MsgIdSet),
+      msg_indices_on_disk = rabbit_misc:gb_sets_difference(MIOD, MsgIdSet),
+      unconfirmed         = rabbit_misc:gb_sets_difference(UC,   MsgIdSet),
+      confirmed           = gb_sets:union(C, MsgIdSet) }.
+
+must_sync_index(#vqstate { msg_indices_on_disk = MIOD,
+                           unconfirmed = UC }) ->
     %% If UC is empty then by definition, MIOD and MOD are also empty
     %% and there's nothing that can be pending a sync.
 
diff --git a/src/rabbit_version.erl b/src/rabbit_version.erl
index f6bcbb7f..1cc7d6c8 100644
--- a/src/rabbit_version.erl
+++ b/src/rabbit_version.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_version).
@@ -96,7 +96,10 @@ record_desired_for_scope(Scope) ->
 upgrades_required(Scope) ->
     case recorded_for_scope(Scope) of
         {error, enoent} ->
-            {error, version_not_available};
+            case filelib:is_file(rabbit_guid:filename()) of
+                false -> {error, starting_from_scratch};
+                true  -> {error, version_not_available}
+            end;
         {ok, CurrentHeads} ->
             with_upgrade_graph(
               fun (G) ->
diff --git a/src/rabbit_vhost.erl b/src/rabbit_vhost.erl
index 38bb76b0..5548ef6d 100644
--- a/src/rabbit_vhost.erl
+++ b/src/rabbit_vhost.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_vhost).
diff --git a/src/rabbit_writer.erl b/src/rabbit_writer.erl
index 091b50e4..f3a8cacf 100644
--- a/src/rabbit_writer.erl
+++ b/src/rabbit_writer.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(rabbit_writer).
@@ -24,7 +24,7 @@
          send_command_and_notify/4, send_command_and_notify/5]).
 -export([internal_send_command/4, internal_send_command/6]).
 
--record(wstate, {sock, channel, frame_max, protocol}).
+-record(wstate, {sock, channel, frame_max, protocol, pending}).
 
 -define(HIBERNATE_AFTER, 5000).
 
@@ -80,7 +80,8 @@ start(Sock, Channel, FrameMax, Protocol, ReaderPid) ->
                                         #wstate{sock = Sock,
                                                 channel = Channel,
                                                 frame_max = FrameMax,
-                                                protocol = Protocol}])}.
+                                                protocol = Protocol,
+                                                pending = []}])}.
 
 start_link(Sock, Channel, FrameMax, Protocol, ReaderPid) ->
     {ok,
@@ -88,7 +89,8 @@ start_link(Sock, Channel, FrameMax, Protocol, ReaderPid) ->
                                              #wstate{sock = Sock,
                                                      channel = Channel,
                                                      frame_max = FrameMax,
-                                                     protocol = Protocol}])}.
+                                                     protocol = Protocol,
+                                                     pending = []}])}.
 
 mainloop(ReaderPid, State) ->
     try
@@ -98,36 +100,43 @@ mainloop(ReaderPid, State) ->
     end,
     done.
 
-mainloop1(ReaderPid, State) ->
+mainloop1(ReaderPid, State = #wstate{pending = []}) ->
     receive
         Message -> ?MODULE:mainloop1(ReaderPid, handle_message(Message, State))
     after ?HIBERNATE_AFTER ->
             erlang:hibernate(?MODULE, mainloop, [ReaderPid, State])
+    end;
+mainloop1(ReaderPid, State) ->
+    receive
+        Message -> ?MODULE:mainloop1(ReaderPid, handle_message(Message, State))
+    after 0 ->
+            ?MODULE:mainloop1(ReaderPid, flush(State))
     end.
 
 handle_message({send_command, MethodRecord}, State) ->
-    ok = internal_send_command_async(MethodRecord, State),
-    State;
+    internal_send_command_async(MethodRecord, State);
 handle_message({send_command, MethodRecord, Content}, State) ->
-    ok = internal_send_command_async(MethodRecord, Content, State),
-    State;
+    internal_send_command_async(MethodRecord, Content, State);
 handle_message({'$gen_call', From, {send_command_sync, MethodRecord}}, State) ->
-    ok = internal_send_command_async(MethodRecord, State),
+    State1 = flush(internal_send_command_async(MethodRecord, State)),
     gen_server:reply(From, ok),
-    State;
+    State1;
 handle_message({'$gen_call', From, {send_command_sync, MethodRecord, Content}},
                State) ->
-    ok = internal_send_command_async(MethodRecord, Content, State),
+    State1 = flush(internal_send_command_async(MethodRecord, Content, State)),
     gen_server:reply(From, ok),
-    State;
+    State1;
 handle_message({send_command_and_notify, QPid, ChPid, MethodRecord}, State) ->
-    ok = internal_send_command_async(MethodRecord, State),
+    State1 = internal_send_command_async(MethodRecord, State),
     rabbit_amqqueue:notify_sent(QPid, ChPid),
-    State;
+    State1;
 handle_message({send_command_and_notify, QPid, ChPid, MethodRecord, Content},
                State) ->
-    ok = internal_send_command_async(MethodRecord, Content, State),
+    State1 = internal_send_command_async(MethodRecord, Content, State),
     rabbit_amqqueue:notify_sent(QPid, ChPid),
+    State1;
+handle_message({'DOWN', _MRef, process, QPid, _Reason}, State) ->
+    rabbit_amqqueue:notify_sent_queue_down(QPid),
     State;
 handle_message({inet_reply, _, ok}, State) ->
     State;
@@ -169,12 +178,10 @@ call(Pid, Msg) ->
 %%---------------------------------------------------------------------------
 
 assemble_frame(Channel, MethodRecord, Protocol) ->
-    ?LOGMESSAGE(out, Channel, MethodRecord, none),
     rabbit_binary_generator:build_simple_method_frame(
       Channel, MethodRecord, Protocol).
 
 assemble_frames(Channel, MethodRecord, Content, FrameMax, Protocol) ->
-    ?LOGMESSAGE(out, Channel, MethodRecord, Content),
     MethodName = rabbit_misc:method_record_type(MethodRecord),
     true = Protocol:method_has_content(MethodName), % assertion
     MethodFrame = rabbit_binary_generator:build_simple_method_frame(
@@ -183,22 +190,6 @@ assemble_frames(Channel, MethodRecord, Content, FrameMax, Protocol) ->
                       Channel, Content, FrameMax, Protocol),
     [MethodFrame | ContentFrames].
 
-%% We optimise delivery of small messages. Content-bearing methods
-%% require at least three frames. Small messages always fit into
-%% that. We hand their frames to the Erlang network functions in one
-%% go, which may lead to somewhat more efficient processing in the
-%% runtime and a greater chance of coalescing into fewer TCP packets.
-%%
-%% By contrast, for larger messages, split across many frames, we want
-%% to allow interleaving of frames on different channels. Hence we
-%% hand them to the Erlang network functions one frame at a time.
-send_frames(Fun, Sock, Frames) when length(Frames) =< 3 ->
-    Fun(Sock, Frames);
-send_frames(Fun, Sock, Frames) ->
-    lists:foldl(fun (Frame,     ok) -> Fun(Sock, Frame);
-                    (_Frame, Other) -> Other
-                end, ok, Frames).
-
 tcp_send(Sock, Data) ->
     rabbit_misc:throw_on_error(inet_error,
                                fun () -> rabbit_net:send(Sock, Data) end).
@@ -208,9 +199,44 @@ internal_send_command(Sock, Channel, MethodRecord, Protocol) ->
 
 internal_send_command(Sock, Channel, MethodRecord, Content, FrameMax,
                       Protocol) ->
-    ok = send_frames(fun tcp_send/2, Sock,
-                     assemble_frames(Channel, MethodRecord,
-                                     Content, FrameMax, Protocol)).
+    ok = lists:foldl(fun (Frame,     ok) -> tcp_send(Sock, Frame);
+                         (_Frame, Other) -> Other
+                     end, ok, assemble_frames(Channel, MethodRecord,
+                                              Content, FrameMax, Protocol)).
+
+internal_send_command_async(MethodRecord,
+                            State = #wstate{channel   = Channel,
+                                            protocol  = Protocol,
+                                            pending   = Pending}) ->
+    Frame = assemble_frame(Channel, MethodRecord, Protocol),
+    maybe_flush(State#wstate{pending = [Frame | Pending]}).
+
+internal_send_command_async(MethodRecord, Content,
+                            State = #wstate{channel   = Channel,
+                                            frame_max = FrameMax,
+                                            protocol  = Protocol,
+                                            pending   = Pending}) ->
+    Frames = assemble_frames(Channel, MethodRecord, Content, FrameMax,
+                             Protocol),
+    maybe_flush(State#wstate{pending = [Frames | Pending]}).
+
+%% This magic number is the tcp-over-ethernet MSS (1460) minus the
+%% minimum size of a AMQP basic.deliver method frame (24) plus basic
+%% content header (22). The idea is that we want to flush just before
+%% exceeding the MSS.
+-define(FLUSH_THRESHOLD, 1414).
+
+maybe_flush(State = #wstate{pending = Pending}) ->
+    case iolist_size(Pending) >= ?FLUSH_THRESHOLD of
+        true  -> flush(State);
+        false -> State
+    end.
+
+flush(State = #wstate{pending = []}) ->
+    State;
+flush(State = #wstate{sock = Sock, pending = Pending}) ->
+    ok = port_cmd(Sock, lists:reverse(Pending)),
+    State#wstate{pending = []}.
 
 %% gen_tcp:send/2 does a selective receive of {inet_reply, Sock,
 %% Status} to obtain the result. That is bad when it is called from
@@ -230,21 +256,6 @@ internal_send_command(Sock, Channel, MethodRecord, Content, FrameMax,
 %% Also note that the port has bounded buffers and port_command blocks
 %% when these are full. So the fact that we process the result
 %% asynchronously does not impact flow control.
-internal_send_command_async(MethodRecord,
-                            #wstate{sock      = Sock,
-                                    channel   = Channel,
-                                    protocol  = Protocol}) ->
-    ok = port_cmd(Sock, assemble_frame(Channel, MethodRecord, Protocol)).
-
-internal_send_command_async(MethodRecord, Content,
-                            #wstate{sock      = Sock,
-                                    channel   = Channel,
-                                    frame_max = FrameMax,
-                                    protocol  = Protocol}) ->
-    ok = send_frames(fun port_cmd/2, Sock,
-                     assemble_frames(Channel, MethodRecord,
-                                     Content, FrameMax, Protocol)).
-
 port_cmd(Sock, Data) ->
     true = try rabbit_net:port_command(Sock, Data)
            catch error:Error -> exit({writer, send_failed, Error})
diff --git a/src/supervisor2.erl b/src/supervisor2.erl
index f75da872..3d3623d7 100644
--- a/src/supervisor2.erl
+++ b/src/supervisor2.erl
@@ -9,15 +9,15 @@
 %%    terminated as per the shutdown component of the child_spec.
 %%
 %% 3) child specifications can contain, as the restart type, a tuple
-%%    {permanent, Delay} | {transient, Delay} where Delay >= 0. The
-%%    delay, in seconds, indicates what should happen if a child, upon
-%%    being restarted, exceeds the MaxT and MaxR parameters. Thus, if
-%%    a child exits, it is restarted as normal. If it exits
-%%    sufficiently quickly and often to exceed the boundaries set by
-%%    the MaxT and MaxR parameters, and a Delay is specified, then
-%%    rather than stopping the supervisor, the supervisor instead
-%%    continues and tries to start up the child again, Delay seconds
-%%    later.
+%%    {permanent, Delay} | {transient, Delay} | {intrinsic, Delay}
+%%    where Delay >= 0 (see point (4) below for intrinsic). The delay,
+%%    in seconds, indicates what should happen if a child, upon being
+%%    restarted, exceeds the MaxT and MaxR parameters. Thus, if a
+%%    child exits, it is restarted as normal. If it exits sufficiently
+%%    quickly and often to exceed the boundaries set by the MaxT and
+%%    MaxR parameters, and a Delay is specified, then rather than
+%%    stopping the supervisor, the supervisor instead continues and
+%%    tries to start up the child again, Delay seconds later.
 %%
 %%    Note that you can never restart more frequently than the MaxT
 %%    and MaxR parameters allow: i.e. you must wait until *both* the
@@ -31,6 +31,16 @@
 %%    the MaxT and MaxR parameters to permit the child to be
 %%    restarted. This may require waiting for longer than Delay.
 %%
+%%    Sometimes, you may wish for a transient or intrinsic child to
+%%    exit abnormally so that it gets restarted, but still log
+%%    nothing. gen_server will log any exit reason other than
+%%    'normal', 'shutdown' or {'shutdown', _}. Thus the exit reason of
+%%    {'shutdown', 'restart'} is interpreted to mean you wish the
+%%    child to be restarted according to the delay parameters, but
+%%    gen_server will not log the error. Thus from gen_server's
+%%    perspective it's a normal exit, whilst from supervisor's
+%%    perspective, it's an abnormal exit.
+%%
 %% 4) Added an 'intrinsic' restart type. Like the transient type, this
 %%    type means the child should only be restarted if the child exits
 %%    abnormally. Unlike the transient type, if the child exits
@@ -41,7 +51,7 @@
 %% 5) normal, and {shutdown, _} exit reasons are all treated the same
 %%    (i.e. are regarded as normal exits)
 %%
-%% All modifications are (C) 2010-2011 VMware, Inc.
+%% All modifications are (C) 2010-2012 VMware, Inc.
 %%
 %% %CopyrightBegin%
 %%
@@ -71,8 +81,6 @@
 	 which_children/1, find_child/2,
 	 check_childspecs/1]).
 
--export([behaviour_info/1]).
-
 %% Internal exports
 -export([init/1, handle_call/3, handle_info/2, terminate/2, code_change/3]).
 -export([handle_cast/2]).
@@ -102,11 +110,144 @@
 -define(is_terminate_simple(State),
         State#state.strategy =:= simple_one_for_one_terminate).
 
+-ifdef(use_specs).
+
+%%--------------------------------------------------------------------------
+%% Types
+%%--------------------------------------------------------------------------
+
+-export_type([child_spec/0, startchild_ret/0, strategy/0, sup_name/0]).
+
+-type child() :: 'undefined' | pid().
+-type child_id() :: term().
+-type mfargs() :: {M :: module(), F :: atom(), A :: [term()] | undefined}.
+-type modules() :: [module()] | 'dynamic'.
+-type delay() :: non_neg_integer().
+-type restart() :: 'permanent' | 'transient' | 'temporary' | 'intrinsic'
+                 | {'permanent', delay()} | {'transient', delay()}
+                 | {'intrinsic', delay()}.
+-type shutdown() :: 'brutal_kill' | timeout().
+-type worker() :: 'worker' | 'supervisor'.
+-type sup_name() :: {'local', Name :: atom()} | {'global', Name :: atom()}.
+-type sup_ref() :: (Name :: atom())
+                  | {Name :: atom(), Node :: node()}
+                  | {'global', Name :: atom()}
+                  | pid().
+-type child_spec() :: {Id :: child_id(),
+                       StartFunc :: mfargs(),
+                       Restart :: restart(),
+                       Shutdown :: shutdown(),
+                       Type :: worker(),
+                       Modules :: modules()}.
+
+
+-type strategy() :: 'one_for_all' | 'one_for_one'
+                  | 'rest_for_one' | 'simple_one_for_one'
+                  | 'simple_one_for_one_terminate'.
+
+-type child_rec() :: #child{pid :: child() | {restarting,pid()} | [pid()],
+                            name :: child_id(),
+                            mfa :: mfargs(),
+                            restart_type :: restart(),
+                            shutdown :: shutdown(),
+                            child_type :: worker(),
+                            modules :: modules()}.
+
+-type state() :: #state{strategy :: strategy(),
+                        children :: [child_rec()],
+                        dynamics :: ?DICT(),
+                        intensity :: non_neg_integer(),
+                        period :: pos_integer()}.
+
+%%--------------------------------------------------------------------------
+%% Callback behaviour
+%%--------------------------------------------------------------------------
+
+-callback init(Args :: term()) ->
+    {ok, {{RestartStrategy :: strategy(),
+           MaxR :: non_neg_integer(),
+           MaxT :: non_neg_integer()},
+           [ChildSpec :: child_spec()]}}
+    | ignore.
+
+%%--------------------------------------------------------------------------
+%% Specs
+%%--------------------------------------------------------------------------
+
+-type startchild_err() :: 'already_present'
+			| {'already_started', Child :: child()} | term().
+-type startchild_ret() :: {'ok', Child :: child()}
+                        | {'ok', Child :: child(), Info :: term()}
+			| {'error', startchild_err()}.
+
+-spec start_child(SupRef, ChildSpec) -> startchild_ret() when
+      SupRef :: sup_ref(),
+      ChildSpec :: child_spec() | (List :: [term()]).
+
+-spec restart_child(SupRef, Id) -> Result when
+      SupRef :: sup_ref(),
+      Id :: child_id(),
+      Result :: {'ok', Child :: child()}
+              | {'ok', Child :: child(), Info :: term()}
+              | {'error', Error},
+      Error :: 'running' | 'not_found' | 'simple_one_for_one' | term().
+
+-spec delete_child(SupRef, Id) -> Result when
+      SupRef :: sup_ref(),
+      Id :: child_id(),
+      Result :: 'ok' | {'error', Error},
+      Error :: 'running' | 'not_found' | 'simple_one_for_one'.
+
+-spec terminate_child(SupRef, Id) -> Result when
+      SupRef :: sup_ref(),
+      Id :: pid() | child_id(),
+      Result :: 'ok' | {'error', Error},
+      Error :: 'not_found' | 'simple_one_for_one'.
+
+-spec which_children(SupRef) -> [{Id,Child,Type,Modules}] when
+      SupRef :: sup_ref(),
+      Id :: child_id() | 'undefined',
+      Child :: child(),
+      Type :: worker(),
+      Modules :: modules().
+
+-spec check_childspecs(ChildSpecs) -> Result when
+      ChildSpecs :: [child_spec()],
+      Result :: 'ok' | {'error', Error :: term()}.
+
+-type init_sup_name() :: sup_name() | 'self'.
+
+-type stop_rsn() :: 'shutdown' | {'bad_return', {module(),'init', term()}}
+                  | {'bad_start_spec', term()} | {'start_spec', term()}
+                  | {'supervisor_data', term()}.
+
+-spec init({init_sup_name(), module(), [term()]}) ->
+        {'ok', state()} | 'ignore' | {'stop', stop_rsn()}.
+
+-type call() :: 'which_children'.
+-spec handle_call(call(), term(), state()) -> {'reply', term(), state()}.
+
+-spec handle_cast('null', state()) -> {'noreply', state()}.
+
+-spec handle_info(term(), state()) ->
+        {'noreply', state()} | {'stop', 'shutdown', state()}.
+
+-spec terminate(term(), state()) -> 'ok'.
+
+-spec code_change(term(), state(), term()) ->
+        {'ok', state()} | {'error', term()}.
+
+-else.
+
+-export([behaviour_info/1]).
+
 behaviour_info(callbacks) ->
     [{init,1}];
 behaviour_info(_Other) ->
     undefined.
 
+-endif.
+
 %%% ---------------------------------------------------
 %%% This is a general process supervisor built upon gen_server.erl.
 %%% Servers/processes should/could also be built using gen_server.erl.
@@ -270,6 +411,8 @@ handle_call({start_child, EArgs}, _From, State) when ?is_simple(State) ->
     #child{mfa = {M, F, A}} = hd(State#state.children),
     Args = A ++ EArgs,
     case do_start_child_i(M, F, Args) of
+        {ok, undefined} ->
+            {reply, {ok, undefined}, State};
 	{ok, Pid} ->
 	    NState = State#state{dynamics = 
 				 ?DICT:store(Pid, Args, State#state.dynamics)},
@@ -529,25 +672,23 @@ restart_child(Pid, Reason, State) ->
 	    {ok, State}
     end.
 
-do_restart({RestartType, Delay}, Reason, Child, State) ->
-    case restart1(Child, State) of
-        {ok, NState} ->
-            {ok, NState};
-        {terminate, NState} ->
-            _TRef = erlang:send_after(trunc(Delay*1000), self(),
-				      {delayed_restart,
-				       {{RestartType, Delay}, Reason, Child}}),
-            {ok, state_del_child(Child, NState)}
-    end;
+do_restart({permanent = RestartType, Delay}, Reason, Child, State) ->
+    do_restart_delay({RestartType, Delay}, Reason, Child, State);
 do_restart(permanent, Reason, Child, State) ->
     report_error(child_terminated, Reason, Child, State#state.name),
     restart(Child, State);
 do_restart(Type, normal, Child, State) ->
     del_child_and_maybe_shutdown(Type, Child, State);
+do_restart({RestartType, Delay}, {shutdown, restart} = Reason, Child, State)
+  when RestartType =:= transient orelse RestartType =:= intrinsic ->
+    do_restart_delay({RestartType, Delay}, Reason, Child, State);
 do_restart(Type, {shutdown, _}, Child, State) ->
     del_child_and_maybe_shutdown(Type, Child, State);
 do_restart(Type, shutdown, Child = #child{child_type = supervisor}, State) ->
     del_child_and_maybe_shutdown(Type, Child, State);
+do_restart({RestartType, Delay}, Reason, Child, State)
+  when RestartType =:= transient orelse RestartType =:= intrinsic ->
+    do_restart_delay({RestartType, Delay}, Reason, Child, State);
 do_restart(Type, Reason, Child, State) when Type =:= transient orelse
                                             Type =:= intrinsic ->
     report_error(child_terminated, Reason, Child, State#state.name),
@@ -557,8 +698,21 @@ do_restart(temporary, Reason, Child, State) ->
     NState = state_del_child(Child, State),
     {ok, NState}.
 
+do_restart_delay({RestartType, Delay}, Reason, Child, State) ->
+    case restart1(Child, State) of
+        {ok, NState} ->
+            {ok, NState};
+        {terminate, NState} ->
+            _TRef = erlang:send_after(trunc(Delay*1000), self(),
+                                      {delayed_restart,
+                                       {{RestartType, Delay}, Reason, Child}}),
+            {ok, state_del_child(Child, NState)}
+    end.
+
 del_child_and_maybe_shutdown(intrinsic, Child, State) ->
     {shutdown, state_del_child(Child, State)};
+del_child_and_maybe_shutdown({intrinsic, _Delay}, Child, State) ->
+    {shutdown, state_del_child(Child, State)};
 del_child_and_maybe_shutdown(_, Child, State) ->
     {ok, state_del_child(Child, State)}.
 
@@ -591,6 +745,8 @@ restart(Strategy, Child, State, Restart)
     #child{mfa = {M, F, A}} = Child,
     Dynamics = ?DICT:erase(Child#child.pid, State#state.dynamics),
     case do_start_child_i(M, F, A) of
+        {ok, undefined} ->
+            {ok, State};
 	{ok, Pid} ->
 	    NState = State#state{dynamics = ?DICT:store(Pid, A, Dynamics)},
 	    {ok, NState};
@@ -717,8 +873,8 @@ do_terminate(Child, SupName) when Child#child.pid =/= undefined ->
             ok;
         {error, normal} ->
             case Child#child.restart_type of
-                permanent           -> ReportError(normal);
-                {permanent, _Delay} -> ReportError(normal);
+                permanent           -> ReportError(normal, Child);
+                {permanent, _Delay} -> ReportError(normal, Child);
                 _                   -> ok
             end;
         {error, OtherReason} ->
@@ -911,7 +1067,8 @@ supname(N,_)      -> N.
 %%%       Func is {Mod, Fun, Args} == {atom, atom, list}
 %%%       RestartType is permanent | temporary | transient |
 %%%                      intrinsic | {permanent, Delay} |
-%%%                      {transient, Delay} where Delay >= 0
+%%%                      {transient, Delay} | {intrinsic, Delay}
+%%                       where Delay >= 0
 %%%       Shutdown = integer() | infinity | brutal_kill
 %%%       ChildType = supervisor | worker
 %%%       Modules = [atom()] | dynamic
@@ -962,6 +1119,7 @@ validRestartType(temporary)          -> true;
 validRestartType(transient)          -> true;
 validRestartType(intrinsic)          -> true;
 validRestartType({permanent, Delay}) -> validDelay(Delay);
+validRestartType({intrinsic, Delay}) -> validDelay(Delay);
 validRestartType({transient, Delay}) -> validDelay(Delay);
 validRestartType(RestartType)        -> throw({invalid_restart_type,
                                                RestartType}).
diff --git a/src/tcp_acceptor.erl b/src/tcp_acceptor.erl
index 0d50683d..344196d7 100644
--- a/src/tcp_acceptor.erl
+++ b/src/tcp_acceptor.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(tcp_acceptor).
@@ -54,28 +54,9 @@ handle_info({inet_async, LSock, Ref, {ok, Sock}},
     {ok, Mod} = inet_db:lookup_socket(LSock),
     inet_db:register_socket(Sock, Mod),
 
-    try
-        %% report
-        {Address, Port}         = inet_op(fun () -> inet:sockname(LSock) end),
-        {PeerAddress, PeerPort} = inet_op(fun () -> inet:peername(Sock) end),
-        error_logger:info_msg("accepted TCP connection on ~s:~p from ~s:~p~n",
-                              [rabbit_misc:ntoab(Address), Port,
-                               rabbit_misc:ntoab(PeerAddress), PeerPort]),
-        %% In the event that somebody floods us with connections we can spew
-        %% the above message at error_logger faster than it can keep up.
-        %% So error_logger's mailbox grows unbounded until we eat all the
-        %% memory available and crash. So here's a meaningless synchronous call
-        %% to the underlying gen_event mechanism - when it returns the mailbox
-        %% is drained.
-        gen_event:which_handlers(error_logger),
-        %% handle
-        file_handle_cache:transfer(apply(M, F, A ++ [Sock])),
-        ok = file_handle_cache:obtain()
-    catch {inet_error, Reason} ->
-            gen_tcp:close(Sock),
-            error_logger:error_msg("unable to accept TCP connection: ~p~n",
-                                   [Reason])
-    end,
+    %% handle
+    file_handle_cache:transfer(apply(M, F, A ++ [Sock])),
+    ok = file_handle_cache:obtain(),
 
     %% accept more
     accept(State);
@@ -86,6 +67,10 @@ handle_info({inet_async, LSock, Ref, {error, closed}},
     %% know this will fail.
     {stop, normal, State};
 
+handle_info({inet_async, LSock, Ref, {error, Reason}},
+            State=#state{sock=LSock, ref=Ref}) ->
+    {stop, {accept_failed, Reason}, State};
+
 handle_info(_Info, State) ->
     {noreply, State}.
 
@@ -97,8 +82,6 @@ code_change(_OldVsn, State, _Extra) ->
 
 %%--------------------------------------------------------------------
 
-inet_op(F) -> rabbit_misc:throw_on_error(inet_error, F).
-
 accept(State = #state{sock=LSock}) ->
     case prim_inet:async_accept(LSock, -1) of
         {ok, Ref} -> {noreply, State#state{ref=Ref}};
diff --git a/src/tcp_acceptor_sup.erl b/src/tcp_acceptor_sup.erl
index 4c835598..d8844441 100644
--- a/src/tcp_acceptor_sup.erl
+++ b/src/tcp_acceptor_sup.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(tcp_acceptor_sup).
@@ -25,7 +25,11 @@
 %%----------------------------------------------------------------------------
 
 -ifdef(use_specs).
--spec(start_link/2 :: (atom(), mfa()) -> rabbit_types:ok_pid_or_error()).
+
+-type(mfargs() :: {atom(), atom(), [any()]}).
+
+-spec(start_link/2 :: (atom(), mfargs()) -> rabbit_types:ok_pid_or_error()).
+
 -endif.
 
 %%----------------------------------------------------------------------------
diff --git a/src/tcp_listener.erl b/src/tcp_listener.erl
index ad2a0d02..fb01c792 100644
--- a/src/tcp_listener.erl
+++ b/src/tcp_listener.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(tcp_listener).
@@ -28,9 +28,14 @@
 %%----------------------------------------------------------------------------
 
 -ifdef(use_specs).
+
+-type(mfargs() :: {atom(), atom(), [any()]}).
+
 -spec(start_link/8 ::
-        (gen_tcp:ip_address(), integer(), rabbit_types:infos(), integer(),
-         atom(), mfa(), mfa(), string()) -> rabbit_types:ok_pid_or_error()).
+        (inet:ip_address(), inet:port_number(), [gen_tcp:listen_option()],
+         integer(), atom(), mfargs(), mfargs(), string()) ->
+                           rabbit_types:ok_pid_or_error()).
+
 -endif.
 
 %%--------------------------------------------------------------------
@@ -67,8 +72,9 @@ init({IPAddress, Port, SocketOpts,
                         label = Label}};
         {error, Reason} ->
             error_logger:error_msg(
-              "failed to start ~s on ~s:~p - ~p~n",
-              [Label, rabbit_misc:ntoab(IPAddress), Port, Reason]),
+              "failed to start ~s on ~s:~p - ~p (~s)~n",
+              [Label, rabbit_misc:ntoab(IPAddress), Port,
+               Reason, inet:format_error(Reason)]),
             {stop, {cannot_listen, IPAddress, Port, Reason}}
     end.
 
diff --git a/src/tcp_listener_sup.erl b/src/tcp_listener_sup.erl
index 5bff5c27..9ee921b4 100644
--- a/src/tcp_listener_sup.erl
+++ b/src/tcp_listener_sup.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(tcp_listener_sup).
@@ -26,12 +26,16 @@
 
 -ifdef(use_specs).
 
+-type(mfargs() :: {atom(), atom(), [any()]}).
+
 -spec(start_link/7 ::
-        (gen_tcp:ip_address(), integer(), rabbit_types:infos(), mfa(), mfa(),
-         mfa(), string()) -> rabbit_types:ok_pid_or_error()).
+        (inet:ip_address(), inet:port_number(), [gen_tcp:listen_option()],
+         mfargs(), mfargs(), mfargs(), string()) ->
+                           rabbit_types:ok_pid_or_error()).
 -spec(start_link/8 ::
-        (gen_tcp:ip_address(), integer(), rabbit_types:infos(), mfa(), mfa(),
-         mfa(), integer(), string()) -> rabbit_types:ok_pid_or_error()).
+        (inet:ip_address(), inet:port_number(), [gen_tcp:listen_option()],
+         mfargs(), mfargs(), mfargs(), integer(), string()) ->
+                           rabbit_types:ok_pid_or_error()).
 
 -endif.
 
diff --git a/src/test_sup.erl b/src/test_sup.erl
index 5feb146f..7f4b5049 100644
--- a/src/test_sup.erl
+++ b/src/test_sup.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(test_sup).
diff --git a/src/vm_memory_monitor.erl b/src/vm_memory_monitor.erl
index 8973a4f7..fb184d1a 100644
--- a/src/vm_memory_monitor.erl
+++ b/src/vm_memory_monitor.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 %% In practice Erlang shouldn't be allowed to grow to more than a half
@@ -181,10 +181,10 @@ internal_update(State = #state { memory_limit = MemLimit,
     case {Alarmed, NewAlarmed} of
         {false, true} ->
             emit_update_info(set, MemUsed, MemLimit),
-            alarm_handler:set_alarm({{vm_memory_high_watermark, node()}, []});
+            alarm_handler:set_alarm({{resource_limit, memory, node()}, []});
         {true, false} ->
             emit_update_info(clear, MemUsed, MemLimit),
-            alarm_handler:clear_alarm({vm_memory_high_watermark, node()});
+            alarm_handler:clear_alarm({resource_limit, memory, node()});
         _ ->
             ok
     end,
diff --git a/src/worker_pool.erl b/src/worker_pool.erl
index 456ff39f..c9ecccd6 100644
--- a/src/worker_pool.erl
+++ b/src/worker_pool.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(worker_pool).
@@ -37,10 +37,11 @@
 
 -ifdef(use_specs).
 
+-type(mfargs() :: {atom(), atom(), [any()]}).
+
 -spec(start_link/0 :: () -> {'ok', pid()} | {'error', any()}).
--spec(submit/1 :: (fun (() -> A) | {atom(), atom(), [any()]}) -> A).
--spec(submit_async/1 ::
-      (fun (() -> any()) | {atom(), atom(), [any()]}) -> 'ok').
+-spec(submit/1 :: (fun (() -> A) | mfargs()) -> A).
+-spec(submit_async/1 :: (fun (() -> any()) | mfargs()) -> 'ok').
 -spec(idle/1 :: (any()) -> 'ok').
 
 -endif.
diff --git a/src/worker_pool_sup.erl b/src/worker_pool_sup.erl
index d37c3a0f..ff356366 100644
--- a/src/worker_pool_sup.erl
+++ b/src/worker_pool_sup.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(worker_pool_sup).
diff --git a/src/worker_pool_worker.erl b/src/worker_pool_worker.erl
index 78ab4df3..1ddcebb2 100644
--- a/src/worker_pool_worker.erl
+++ b/src/worker_pool_worker.erl
@@ -11,7 +11,7 @@
 %% The Original Code is RabbitMQ.
 %%
 %% The Initial Developer of the Original Code is VMware, Inc.
-%% Copyright (c) 2007-2011 VMware, Inc.  All rights reserved.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
 %%
 
 -module(worker_pool_worker).
@@ -29,12 +29,12 @@
 
 -ifdef(use_specs).
 
+-type(mfargs() :: {atom(), atom(), [any()]}).
+
 -spec(start_link/1 :: (any()) -> {'ok', pid()} | {'error', any()}).
--spec(submit/2 :: (pid(), fun (() -> A) | {atom(), atom(), [any()]}) -> A).
--spec(submit_async/2 ::
-      (pid(), fun (() -> any()) | {atom(), atom(), [any()]}) -> 'ok').
--spec(run/1 :: (fun (() -> A)) -> A;
-               ({atom(), atom(), [any()]}) -> any()).
+-spec(submit/2 :: (pid(), fun (() -> A) | mfargs()) -> A).
+-spec(submit_async/2 :: (pid(), fun (() -> any()) | mfargs()) -> 'ok').
+-spec(run/1 :: (fun (() -> A)) -> A; (mfargs()) -> any()).
 -spec(set_maximum_since_use/2 :: (pid(), non_neg_integer()) -> 'ok').
 
 -endif.