Merge pull request #331 from patcoll/OHAI-431

OHAI-431: provide basic memory information for Mac OS X

2 files changed, 127 insertions, 0 deletions

diff --git a/lib/ohai/plugins/darwin/memory.rb b/lib/ohai/plugins/darwin/memory.rb
new file mode 100644
index 00000000..62237a7d
--- /dev/null
+++ b/lib/ohai/plugins/darwin/memory.rb
@@ -0,0 +1,63 @@
+#
+# Author:: Patrick Collins (<pat@burned.com>)
+# Copyright:: Copyright (c) 2013 Opscode, Inc.
+# License:: Apache License, Version 2.0
+#
+# Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+Ohai.plugin(:Memory) do
+  provides 'memory'
+
+  collect_data(:darwin) do
+    memory Mash.new
+
+    installed_memory = shell_out("sysctl -n hw.memsize").stdout.to_i / 1024 / 1024.0
+    memory[:total] = "#{installed_memory.to_i}MB"
+
+    total_consumed = 0
+    active = 0
+    inactive = 0
+    vm_stat = shell_out("vm_stat").stdout
+    vm_stat_match = /page size of (\d+) bytes/.match(vm_stat)
+    page_size = if vm_stat_match and vm_stat_match[1]
+      vm_stat_match[1].to_i
+    else
+      4096
+    end
+    vm_stat.split("\n").each do |line|
+      ['wired down', 'active', 'inactive'].each do |match|
+        unless line.index("Pages #{match}:").nil?
+          pages = line.split.last.to_i
+          megabyte_val = (pages * page_size) / 1024 / 1024.0
+          total_consumed += megabyte_val
+          case match
+          when 'wired down'
+            active += megabyte_val.to_i
+          when 'active'
+            active += megabyte_val.to_i
+          when 'inactive'
+            inactive += megabyte_val.to_i
+          end
+        end
+      end
+    end
+
+    memory[:active] = "#{active}MB" if active > 0
+    memory[:inactive] = "#{inactive}MB" if inactive > 0
+
+    free_memory = installed_memory - total_consumed
+    memory[:free] = "#{free_memory.to_i}MB" if total_consumed > 0
+  end
+end
+
diff --git a/spec/unit/plugins/darwin/memory_spec.rb b/spec/unit/plugins/darwin/memory_spec.rb
new file mode 100644
index 00000000..17595ae8
--- /dev/null
+++ b/spec/unit/plugins/darwin/memory_spec.rb
@@ -0,0 +1,64 @@
+#
+# Author:: Patrick Collins (<pat@burned.com>)
+# Copyright:: Copyright (c) 2013 Opscode, Inc.
+# License:: Apache License, Version 2.0
+#
+# Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+require File.expand_path(File.dirname(__FILE__) + '/../../../spec_helper.rb')
+
+describe Ohai::System, "Darwin Memory Plugin" do
+  before(:each) do
+    darwin_memsize = <<-DARWIN_MEMSIZE
+17179869184
+    DARWIN_MEMSIZE
+    darwin_vm_stat = <<-DARWIN_VM_STAT
+Mach Virtual Memory Statistics: (page size of 4096 bytes)
+Pages free:                        2155305.
+Pages active:                       924164.
+Pages inactive:                     189127.
+Pages speculative:                  531321.
+Pages wired down:                   391749.
+"Translation faults":             14107520.
+Pages copy-on-write:                810071.
+Pages zero filled:                 6981505.
+Pages reactivated:                    1397.
+Pageins:                            630064.
+Pageouts:                                0.
+Object cache: 12 hits of 139872 lookups (0% hit rate)
+    DARWIN_VM_STAT
+
+    @plugin = get_plugin("darwin/memory")
+    @plugin.stub(:collect_os).and_return(:darwin)
+    @plugin.stub(:shell_out).with("sysctl -n hw.memsize").and_return(mock_shell_out(0, darwin_memsize, ""))
+    @plugin.stub(:shell_out).with("vm_stat").and_return(mock_shell_out(0, darwin_vm_stat, ""))
+    @plugin.run
+  end
+
+  it "should set memory[:total] to 16384MB" do
+    @plugin[:memory][:total].should == '16384MB'
+  end
+
+  it "should set memory[:active] to 5140MB" do
+    @plugin[:memory][:active].should == '5140MB'
+  end
+
+  it "should set memory[:inactive] to 738MB" do
+    @plugin[:memory][:inactive].should == '738MB'
+  end
+
+  it "should set memory[:free] to 10504MB" do
+    @plugin[:memory][:free].should == '10504MB'
+  end
+end