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|
%% 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.
%%
-module(rabbit_variable_queue).
-export([init/4, terminate/1, delete_and_terminate/1,
purge/1, publish/4, publish_delivered/5, drain_confirmed/1,
fetch/2, ack/2, tx_publish/5, tx_ack/3, tx_rollback/2, tx_commit/4,
requeue/3, len/1, is_empty/1, dropwhile/2,
set_ram_duration_target/2, ram_duration/1,
needs_idle_timeout/1, idle_timeout/1, handle_pre_hibernate/1,
status/1, invoke/3, is_duplicate/3, discard/3,
multiple_routing_keys/0]).
-export([start/1, stop/0]).
%% exported for testing only
-export([start_msg_store/2, stop_msg_store/0, init/6]).
%%----------------------------------------------------------------------------
%% Definitions:
%% alpha: this is a message where both the message itself, and its
%% position within the queue are held in RAM
%%
%% beta: this is a message where the message itself is only held on
%% disk, but its position within the queue is held in RAM.
%%
%% gamma: this is a message where the message itself is only held on
%% disk, but its position is both in RAM and on disk.
%%
%% delta: this is a collection of messages, represented by a single
%% term, where the messages and their position are only held on
%% disk.
%%
%% Note that for persistent messages, the message and its position
%% within the queue are always held on disk, *in addition* to being in
%% one of the above classifications.
%%
%% Also note that within this code, the term gamma never
%% appears. Instead, gammas are defined by betas who have had their
%% queue position recorded on disk.
%%
%% In general, messages move q1 -> q2 -> delta -> q3 -> q4, though
%% many of these steps are frequently skipped. q1 and q4 only hold
%% alphas, q2 and q3 hold both betas and gammas (as queues of queues,
%% using the bpqueue module where the block prefix determines whether
%% they're betas or gammas). When a message arrives, its
%% classification is determined. It is then added to the rightmost
%% appropriate queue.
%%
%% If a new message is determined to be a beta or gamma, q1 is
%% empty. If a new message is determined to be a delta, q1 and q2 are
%% empty (and actually q4 too).
%%
%% When removing messages from a queue, if q4 is empty then q3 is read
%% directly. If q3 becomes empty then the next segment's worth of
%% messages from delta are read into q3, reducing the size of
%% delta. If the queue is non empty, either q4 or q3 contain
%% entries. It is never permitted for delta to hold all the messages
%% in the queue.
%%
%% The duration indicated to us by the memory_monitor is used to
%% calculate, given our current ingress and egress rates, how many
%% messages we should hold in RAM. We track the ingress and egress
%% rates for both messages and pending acks and rates for both are
%% considered when calculating the number of messages to hold in
%% RAM. When we need to push alphas to betas or betas to gammas, we
%% favour writing out messages that are further from the head of the
%% queue. This minimises writes to disk, as the messages closer to the
%% tail of the queue stay in the queue for longer, thus do not need to
%% be replaced as quickly by sending other messages to disk.
%%
%% Whilst messages are pushed to disk and forgotten from RAM as soon
%% as requested by a new setting of the queue RAM duration, the
%% inverse is not true: we only load messages back into RAM as
%% demanded as the queue is read from. Thus only publishes to the
%% queue will take up available spare capacity.
%%
%% When we report our duration to the memory monitor, we calculate
%% average ingress and egress rates over the last two samples, and
%% then calculate our duration based on the sum of the ingress and
%% egress rates. More than two samples could be used, but it's a
%% balance between responding quickly enough to changes in
%% producers/consumers versus ignoring temporary blips. The problem
%% with temporary blips is that with just a few queues, they can have
%% substantial impact on the calculation of the average duration and
%% hence cause unnecessary I/O. Another alternative is to increase the
%% amqqueue_process:RAM_DURATION_UPDATE_PERIOD to beyond 5
%% seconds. However, that then runs the risk of being too slow to
%% inform the memory monitor of changes. Thus a 5 second interval,
%% plus a rolling average over the last two samples seems to work
%% well in practice.
%%
%% The sum of the ingress and egress rates is used because the egress
%% rate alone is not sufficient. Adding in the ingress rate means that
%% queues which are being flooded by messages are given more memory,
%% resulting in them being able to process the messages faster (by
%% doing less I/O, or at least deferring it) and thus helping keep
%% their mailboxes empty and thus the queue as a whole is more
%% responsive. If such a queue also has fast but previously idle
%% consumers, the consumer can then start to be driven as fast as it
%% can go, whereas if only egress rate was being used, the incoming
%% messages may have to be written to disk and then read back in,
%% resulting in the hard disk being a bottleneck in driving the
%% consumers. Generally, we want to give Rabbit every chance of
%% getting rid of messages as fast as possible and remaining
%% responsive, and using only the egress rate impacts that goal.
%%
%% If a queue is full of transient messages, then the transition from
%% betas to deltas will be potentially very expensive as millions of
%% entries must be written to disk by the queue_index module. This can
%% badly stall the queue. In order to avoid this, the proportion of
%% gammas / (betas+gammas) must not be lower than (betas+gammas) /
%% (alphas+betas+gammas). As the queue grows or available memory
%% shrinks, the latter ratio increases, requiring the conversion of
%% more gammas to betas in order to maintain the invariant. At the
%% point at which betas and gammas must be converted to deltas, there
%% should be very few betas remaining, thus the transition is fast (no
%% work needs to be done for the gamma -> delta transition).
%%
%% The conversion of betas to gammas is done in batches of exactly
%% ?IO_BATCH_SIZE. This value should not be too small, otherwise the
%% frequent operations on the queues of q2 and q3 will not be
%% effectively amortised (switching the direction of queue access
%% defeats amortisation), nor should it be too big, otherwise
%% converting a batch stalls the queue for too long. Therefore, it
%% must be just right. ram_index_count is used here and is the number
%% of betas.
%%
%% The conversion from alphas to betas is also chunked, but only to
%% ensure no more than ?IO_BATCH_SIZE alphas are converted to betas at
%% any one time. This further smooths the effects of changes to the
%% target_ram_count and ensures the queue remains responsive
%% even when there is a large amount of IO work to do. The
%% idle_timeout callback is utilised to ensure that conversions are
%% done as promptly as possible whilst ensuring the queue remains
%% responsive.
%%
%% In the queue we keep track of both messages that are pending
%% delivery and messages that are pending acks. In the event of a
%% queue purge, we only need to load qi segments if the queue has
%% elements in deltas (i.e. it came under significant memory
%% pressure). In the event of a queue deletion, in addition to the
%% preceding, by keeping track of pending acks in RAM, we do not need
%% to search through qi segments looking for messages that are yet to
%% be acknowledged.
%%
%% Pending acks are recorded in memory either as the tuple {SeqId,
%% MsgId, MsgProps} (tuple-form) or as the message itself (message-
%% form). Acks for persistent messages are always stored in the tuple-
%% form. Acks for transient messages are also stored in tuple-form if
%% the message has been sent to disk as part of the memory reduction
%% process. For transient messages that haven't already been written
%% to disk, acks are stored in message-form.
%%
%% During memory reduction, acks stored in message-form are converted
%% to tuple-form, and the corresponding messages are pushed out to
%% disk.
%%
%% The order in which alphas are pushed to betas and message-form acks
%% are pushed to disk is determined dynamically. We always prefer to
%% push messages for the source (alphas or acks) that is growing the
%% fastest (with growth measured as avg. ingress - avg. egress). In
%% each round of memory reduction a chunk of messages at most
%% ?IO_BATCH_SIZE in size is allocated to be pushed to disk. The
%% fastest growing source will be reduced by as much of this chunk as
%% possible. If there is any remaining allocation in the chunk after
%% the first source has been reduced to zero, the second source will
%% be reduced by as much of the remaining chunk as possible.
%%
%% Notes on Clean Shutdown
%% (This documents behaviour in variable_queue, queue_index and
%% msg_store.)
%%
%% In order to try to achieve as fast a start-up as possible, if a
%% clean shutdown occurs, we try to save out state to disk to reduce
%% work on startup. In the msg_store this takes the form of the
%% index_module's state, plus the file_summary ets table, and client
%% refs. In the VQ, this takes the form of the count of persistent
%% messages in the queue and references into the msg_stores. The
%% queue_index adds to these terms the details of its segments and
%% stores the terms in the queue directory.
%%
%% Two message stores are used. One is created for persistent messages
%% to durable queues that must survive restarts, and the other is used
%% for all other messages that just happen to need to be written to
%% disk. On start up we can therefore nuke the transient message
%% store, and be sure that the messages in the persistent store are
%% all that we need.
%%
%% The references to the msg_stores are there so that the msg_store
%% knows to only trust its saved state if all of the queues it was
%% previously talking to come up cleanly. Likewise, the queues
%% themselves (esp queue_index) skips work in init if all the queues
%% and msg_store were shutdown cleanly. This gives both good speed
%% improvements and also robustness so that if anything possibly went
%% wrong in shutdown (or there was subsequent manual tampering), all
%% messages and queues that can be recovered are recovered, safely.
%%
%% To delete transient messages lazily, the variable_queue, on
%% startup, stores the next_seq_id reported by the queue_index as the
%% transient_threshold. From that point on, whenever it's reading a
%% message off disk via the queue_index, if the seq_id is below this
%% threshold and the message is transient then it drops the message
%% (the message itself won't exist on disk because it would have been
%% stored in the transient msg_store which would have had its saved
%% state nuked on startup). This avoids the expensive operation of
%% scanning the entire queue on startup in order to delete transient
%% messages that were only pushed to disk to save memory.
%%
%%----------------------------------------------------------------------------
-behaviour(rabbit_backing_queue).
-record(vqstate,
{ q1,
q2,
delta,
q3,
q4,
next_seq_id,
pending_ack,
pending_ack_index,
ram_ack_index,
index_state,
msg_store_clients,
on_sync,
durable,
transient_threshold,
async_callback,
sync_callback,
len,
persistent_count,
target_ram_count,
ram_msg_count,
ram_msg_count_prev,
ram_ack_count_prev,
ram_index_count,
out_counter,
in_counter,
rates,
msgs_on_disk,
msg_indices_on_disk,
unconfirmed,
confirmed,
ack_out_counter,
ack_in_counter,
ack_rates
}).
-record(rates, { egress, ingress, avg_egress, avg_ingress, timestamp }).
-record(msg_status,
{ seq_id,
msg_id,
msg,
is_persistent,
is_delivered,
msg_on_disk,
index_on_disk,
msg_props
}).
-record(delta,
{ start_seq_id, %% start_seq_id is inclusive
count,
end_seq_id %% end_seq_id is exclusive
}).
-record(tx, { pending_messages, pending_acks }).
-record(sync, { acks_persistent, acks_all, pubs, funs }).
%% When we discover, on publish, that we should write some indices to
%% disk for some betas, the IO_BATCH_SIZE sets the number of betas
%% that we must be due to write indices for before we do any work at
%% all. This is both a minimum and a maximum - we don't write fewer
%% than IO_BATCH_SIZE indices out in one go, and we don't write more -
%% we can always come back on the next publish to do more.
-define(IO_BATCH_SIZE, 64).
-define(PERSISTENT_MSG_STORE, msg_store_persistent).
-define(TRANSIENT_MSG_STORE, msg_store_transient).
-include("rabbit.hrl").
%%----------------------------------------------------------------------------
-rabbit_upgrade({multiple_routing_keys, local, []}).
-ifdef(use_specs).
-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()},
avg_egress :: float(),
avg_ingress :: float(),
timestamp :: timestamp() }).
-type(delta() :: #delta { start_seq_id :: non_neg_integer(),
count :: non_neg_integer(),
end_seq_id :: non_neg_integer() }).
-type(sync() :: #sync { acks_persistent :: [[seq_id()]],
acks_all :: [[seq_id()]],
pubs :: [{message_properties_transformer(),
[rabbit_types:basic_message()]}],
funs :: [fun (() -> any())] }).
-type(state() :: #vqstate {
q1 :: queue(),
q2 :: bpqueue:bpqueue(),
delta :: delta(),
q3 :: bpqueue:bpqueue(),
q4 :: queue(),
next_seq_id :: seq_id(),
pending_ack :: dict(),
ram_ack_index :: gb_tree(),
index_state :: any(),
msg_store_clients :: 'undefined' | {{any(), binary()},
{any(), binary()}},
on_sync :: sync(),
durable :: boolean(),
transient_threshold :: non_neg_integer(),
async_callback :: async_callback(),
sync_callback :: sync_callback(),
len :: non_neg_integer(),
persistent_count :: non_neg_integer(),
target_ram_count :: non_neg_integer() | 'infinity',
ram_msg_count :: non_neg_integer(),
ram_msg_count_prev :: non_neg_integer(),
ram_index_count :: non_neg_integer(),
out_counter :: non_neg_integer(),
in_counter :: non_neg_integer(),
rates :: rates(),
msgs_on_disk :: gb_set(),
msg_indices_on_disk :: gb_set(),
unconfirmed :: gb_set(),
confirmed :: gb_set(),
ack_out_counter :: non_neg_integer(),
ack_in_counter :: non_neg_integer(),
ack_rates :: rates() }).
-include("rabbit_backing_queue_spec.hrl").
-spec(multiple_routing_keys/0 :: () -> 'ok').
-endif.
-define(BLANK_DELTA, #delta { start_seq_id = undefined,
count = 0,
end_seq_id = undefined }).
-define(BLANK_DELTA_PATTERN(Z), #delta { start_seq_id = Z,
count = 0,
end_seq_id = Z }).
-define(BLANK_SYNC, #sync { acks_persistent = [],
acks_all = [],
pubs = [],
funs = [] }).
%%----------------------------------------------------------------------------
%% Public API
%%----------------------------------------------------------------------------
start(DurableQueues) ->
{AllTerms, StartFunState} = rabbit_queue_index:recover(DurableQueues),
start_msg_store(
[Ref || Terms <- AllTerms,
begin
Ref = proplists:get_value(persistent_ref, Terms),
Ref =/= undefined
end],
StartFunState).
stop() -> stop_msg_store().
start_msg_store(Refs, StartFunState) ->
ok = rabbit_sup:start_child(?TRANSIENT_MSG_STORE, rabbit_msg_store,
[?TRANSIENT_MSG_STORE, rabbit_mnesia:dir(),
undefined, {fun (ok) -> finished end, ok}]),
ok = rabbit_sup:start_child(?PERSISTENT_MSG_STORE, rabbit_msg_store,
[?PERSISTENT_MSG_STORE, rabbit_mnesia:dir(),
Refs, StartFunState]).
stop_msg_store() ->
ok = rabbit_sup:stop_child(?PERSISTENT_MSG_STORE),
ok = rabbit_sup:stop_child(?TRANSIENT_MSG_STORE).
init(Queue, Recover, AsyncCallback, SyncCallback) ->
init(Queue, Recover, AsyncCallback, SyncCallback,
fun (MsgIds, ActionTaken) ->
msgs_written_to_disk(AsyncCallback, MsgIds, ActionTaken)
end,
fun (MsgIds) -> msg_indices_written_to_disk(AsyncCallback, MsgIds) end).
init(#amqqueue { name = QueueName, durable = IsDurable }, false,
AsyncCallback, SyncCallback, MsgOnDiskFun, MsgIdxOnDiskFun) ->
IndexState = rabbit_queue_index:init(QueueName, MsgIdxOnDiskFun),
init(IsDurable, IndexState, 0, [], AsyncCallback, SyncCallback,
case IsDurable of
true -> msg_store_client_init(?PERSISTENT_MSG_STORE,
MsgOnDiskFun, AsyncCallback);
false -> undefined
end,
msg_store_client_init(?TRANSIENT_MSG_STORE, undefined, AsyncCallback));
init(#amqqueue { name = QueueName, durable = true }, true,
AsyncCallback, SyncCallback, MsgOnDiskFun, MsgIdxOnDiskFun) ->
Terms = rabbit_queue_index:shutdown_terms(QueueName),
{PRef, TRef, Terms1} =
case [persistent_ref, transient_ref] -- proplists:get_keys(Terms) of
[] -> {proplists:get_value(persistent_ref, Terms),
proplists:get_value(transient_ref, Terms),
Terms};
_ -> {rabbit_guid:guid(), rabbit_guid:guid(), []}
end,
PersistentClient = msg_store_client_init(?PERSISTENT_MSG_STORE, PRef,
MsgOnDiskFun, AsyncCallback),
TransientClient = msg_store_client_init(?TRANSIENT_MSG_STORE, TRef,
undefined, AsyncCallback),
{DeltaCount, IndexState} =
rabbit_queue_index:recover(
QueueName, Terms1,
rabbit_msg_store:successfully_recovered_state(?PERSISTENT_MSG_STORE),
fun (MsgId) ->
rabbit_msg_store:contains(MsgId, PersistentClient)
end,
MsgIdxOnDiskFun),
init(true, IndexState, DeltaCount, Terms1, AsyncCallback, SyncCallback,
PersistentClient, TransientClient).
terminate(State) ->
State1 = #vqstate { persistent_count = PCount,
index_state = IndexState,
msg_store_clients = {MSCStateP, MSCStateT} } =
remove_pending_ack(true, tx_commit_index(State)),
PRef = case MSCStateP of
undefined -> undefined;
_ -> ok = rabbit_msg_store:client_terminate(MSCStateP),
rabbit_msg_store:client_ref(MSCStateP)
end,
ok = rabbit_msg_store:client_terminate(MSCStateT),
TRef = rabbit_msg_store:client_ref(MSCStateT),
Terms = [{persistent_ref, PRef},
{transient_ref, TRef},
{persistent_count, PCount}],
a(State1 #vqstate { index_state = rabbit_queue_index:terminate(
Terms, IndexState),
msg_store_clients = undefined }).
%% the only difference between purge and delete is that delete also
%% needs to delete everything that's been delivered and not ack'd.
delete_and_terminate(State) ->
%% TODO: there is no need to interact with qi at all - which we do
%% as part of 'purge' and 'remove_pending_ack', other than
%% deleting it.
{_PurgeCount, State1} = purge(State),
State2 = #vqstate { index_state = IndexState,
msg_store_clients = {MSCStateP, MSCStateT} } =
remove_pending_ack(false, State1),
IndexState1 = rabbit_queue_index:delete_and_terminate(IndexState),
case MSCStateP of
undefined -> ok;
_ -> rabbit_msg_store:client_delete_and_terminate(MSCStateP)
end,
rabbit_msg_store:client_delete_and_terminate(MSCStateT),
a(State2 #vqstate { index_state = IndexState1,
msg_store_clients = undefined }).
purge(State = #vqstate { q4 = Q4,
index_state = IndexState,
msg_store_clients = MSCState,
len = Len,
persistent_count = PCount }) ->
%% TODO: when there are no pending acks, which is a common case,
%% we could simply wipe the qi instead of issuing delivers and
%% acks for all the messages.
{LensByStore, IndexState1} = remove_queue_entries(
fun rabbit_misc:queue_fold/3, Q4,
orddict:new(), IndexState, MSCState),
{LensByStore1, State1 = #vqstate { q1 = Q1,
index_state = IndexState2,
msg_store_clients = MSCState1 }} =
purge_betas_and_deltas(LensByStore,
State #vqstate { q4 = queue:new(),
index_state = IndexState1 }),
{LensByStore2, IndexState3} = remove_queue_entries(
fun rabbit_misc:queue_fold/3, Q1,
LensByStore1, IndexState2, MSCState1),
PCount1 = PCount - find_persistent_count(LensByStore2),
{Len, a(State1 #vqstate { q1 = queue:new(),
index_state = IndexState3,
len = 0,
ram_msg_count = 0,
ram_index_count = 0,
persistent_count = PCount1 })}.
publish(Msg, MsgProps, _ChPid, State) ->
{_SeqId, State1} = publish(Msg, MsgProps, false, false, State),
a(reduce_memory_use(State1)).
publish_delivered(false, #basic_message { id = MsgId },
#message_properties { needs_confirming = NeedsConfirming },
_ChPid, State = #vqstate { async_callback = Callback,
len = 0 }) ->
case NeedsConfirming of
true -> blind_confirm(Callback, gb_sets:singleton(MsgId));
false -> ok
end,
{undefined, a(State)};
publish_delivered(true, Msg = #basic_message { is_persistent = IsPersistent,
id = MsgId },
MsgProps = #message_properties {
needs_confirming = NeedsConfirming },
_ChPid, State = #vqstate { len = 0,
next_seq_id = SeqId,
out_counter = OutCount,
in_counter = InCount,
persistent_count = PCount,
durable = IsDurable,
unconfirmed = UC }) ->
IsPersistent1 = IsDurable andalso IsPersistent,
MsgStatus = (msg_status(IsPersistent1, SeqId, Msg, MsgProps))
#msg_status { is_delivered = true },
{MsgStatus1, State1} = maybe_write_to_disk(false, false, MsgStatus, State),
State2 = record_pending_ack(m(MsgStatus1), State1),
PCount1 = PCount + one_if(IsPersistent1),
UC1 = gb_sets_maybe_insert(NeedsConfirming, MsgId, UC),
{SeqId, a(reduce_memory_use(
State2 #vqstate { next_seq_id = SeqId + 1,
out_counter = OutCount + 1,
in_counter = InCount + 1,
persistent_count = PCount1,
unconfirmed = UC1 }))}.
drain_confirmed(State = #vqstate { confirmed = C }) ->
{gb_sets:to_list(C), State #vqstate { confirmed = gb_sets:new() }}.
dropwhile(Pred, State) ->
{_OkOrEmpty, State1} = dropwhile1(Pred, State),
a(State1).
dropwhile1(Pred, State) ->
internal_queue_out(
fun(MsgStatus = #msg_status { msg_props = MsgProps, msg = Msg,
index_on_disk = IndexOnDisk },
State1 = #vqstate { q3 = Q3, q4 = Q4,
ram_index_count = RamIndexCount }) ->
case Pred(MsgProps) of
true ->
{_, State2} = internal_fetch(false, MsgStatus, State1),
dropwhile1(Pred, State2);
false ->
{ok,
case Msg of
undefined ->
true = queue:is_empty(Q4), %% ASSERTION
Q3a = bpqueue:in_r(IndexOnDisk, MsgStatus, Q3),
RamIndexCount1 =
RamIndexCount + one_if(not IndexOnDisk),
State1 #vqstate {
q3 = Q3a, ram_index_count = RamIndexCount1 };
_ ->
Q4a = queue:in_r(MsgStatus, Q4),
State1 #vqstate { q4 = Q4a }
end}
end
end, State).
fetch(AckRequired, State) ->
internal_queue_out(
fun(MsgStatus, State1) ->
%% it's possible that the message wasn't read from disk
%% at this point, so read it in.
{MsgStatus1, State2} = read_msg(MsgStatus, State1),
internal_fetch(AckRequired, MsgStatus1, State2)
end, State).
internal_queue_out(Fun, State = #vqstate { q4 = Q4 }) ->
case queue:out(Q4) of
{empty, _Q4} ->
case fetch_from_q3(State) of
{empty, State1} = Result -> a(State1), Result;
{loaded, {MsgStatus, State1}} -> Fun(MsgStatus, State1)
end;
{{value, MsgStatus}, Q4a} ->
Fun(MsgStatus, State #vqstate { q4 = Q4a })
end.
read_msg(MsgStatus = #msg_status { msg = undefined,
msg_id = MsgId,
is_persistent = IsPersistent },
State = #vqstate { ram_msg_count = RamMsgCount,
msg_store_clients = MSCState}) ->
{{ok, Msg = #basic_message {}}, MSCState1} =
msg_store_read(MSCState, IsPersistent, MsgId),
{MsgStatus #msg_status { msg = Msg },
State #vqstate { ram_msg_count = RamMsgCount + 1,
msg_store_clients = MSCState1 }};
read_msg(MsgStatus, State) ->
{MsgStatus, State}.
internal_fetch(AckRequired, MsgStatus = #msg_status {
seq_id = SeqId,
msg_id = MsgId,
msg = Msg,
is_persistent = IsPersistent,
is_delivered = IsDelivered,
msg_on_disk = MsgOnDisk,
index_on_disk = IndexOnDisk },
State = #vqstate {ram_msg_count = RamMsgCount,
out_counter = OutCount,
index_state = IndexState,
msg_store_clients = MSCState,
len = Len,
persistent_count = PCount }) ->
%% 1. Mark it delivered if necessary
IndexState1 = maybe_write_delivered(
IndexOnDisk andalso not IsDelivered,
SeqId, IndexState),
%% 2. Remove from msg_store and queue index, if necessary
Rem = fun () ->
ok = msg_store_remove(MSCState, IsPersistent, [MsgId])
end,
Ack = fun () -> rabbit_queue_index:ack([SeqId], IndexState1) end,
IndexState2 =
case {AckRequired, MsgOnDisk, IndexOnDisk, IsPersistent} of
{false, true, false, _} -> Rem(), IndexState1;
{false, true, true, _} -> Rem(), Ack();
{ true, true, true, false} -> Ack();
_ -> IndexState1
end,
%% 3. If an ack is required, add something sensible to PA
{AckTag, State1} = case AckRequired of
true -> StateN = record_pending_ack(
MsgStatus #msg_status {
is_delivered = true }, State),
{SeqId, StateN};
false -> {undefined, State}
end,
PCount1 = PCount - one_if(IsPersistent andalso not AckRequired),
Len1 = Len - 1,
RamMsgCount1 = RamMsgCount - one_if(Msg =/= undefined),
{{Msg, IsDelivered, AckTag, Len1},
a(State1 #vqstate { ram_msg_count = RamMsgCount1,
out_counter = OutCount + 1,
index_state = IndexState2,
len = Len1,
persistent_count = PCount1 })}.
ack(AckTags, State) ->
{MsgIds, State1} = ack(fun msg_store_remove/3,
fun (_, State0) -> State0 end,
AckTags, State),
{MsgIds, a(State1)}.
tx_publish(Txn, Msg = #basic_message { is_persistent = IsPersistent }, MsgProps,
_ChPid, State = #vqstate { durable = IsDurable,
msg_store_clients = MSCState }) ->
Tx = #tx { pending_messages = Pubs } = lookup_tx(Txn),
store_tx(Txn, Tx #tx { pending_messages = [{Msg, MsgProps} | Pubs] }),
case IsPersistent andalso IsDurable of
true -> MsgStatus = msg_status(true, undefined, Msg, MsgProps),
#msg_status { msg_on_disk = true } =
maybe_write_msg_to_disk(false, MsgStatus, MSCState);
false -> ok
end,
a(State).
tx_ack(Txn, AckTags, State) ->
Tx = #tx { pending_acks = Acks } = lookup_tx(Txn),
store_tx(Txn, Tx #tx { pending_acks = [AckTags | Acks] }),
State.
tx_rollback(Txn, State = #vqstate { durable = IsDurable,
msg_store_clients = MSCState }) ->
#tx { pending_acks = AckTags, pending_messages = Pubs } = lookup_tx(Txn),
erase_tx(Txn),
ok = case IsDurable of
true -> msg_store_remove(MSCState, true,
persistent_msg_ids(Pubs));
false -> ok
end,
{lists:append(AckTags), a(State)}.
tx_commit(Txn, Fun, MsgPropsFun,
State = #vqstate { durable = IsDurable,
async_callback = AsyncCallback,
sync_callback = SyncCallback,
msg_store_clients = MSCState }) ->
#tx { pending_acks = AckTags, pending_messages = Pubs } = lookup_tx(Txn),
erase_tx(Txn),
AckTags1 = lists:append(AckTags),
PersistentMsgIds = persistent_msg_ids(Pubs),
HasPersistentPubs = PersistentMsgIds =/= [],
{AckTags1,
a(case IsDurable andalso HasPersistentPubs of
true -> MsgStoreCallback =
fun () -> msg_store_callback(
PersistentMsgIds, Pubs, AckTags1, Fun,
MsgPropsFun, AsyncCallback, SyncCallback)
end,
ok = msg_store_sync(MSCState, true, PersistentMsgIds,
fun () -> spawn(MsgStoreCallback) end),
State;
false -> tx_commit_post_msg_store(HasPersistentPubs, Pubs, AckTags1,
Fun, MsgPropsFun, State)
end)}.
requeue(AckTags, MsgPropsFun, State) ->
MsgPropsFun1 = fun (MsgProps) ->
(MsgPropsFun(MsgProps)) #message_properties {
needs_confirming = false }
end,
{MsgIds, State1} =
ack(fun (_, _, _) -> ok end,
fun (#msg_status { msg = Msg, msg_props = MsgProps }, State1) ->
{_SeqId, State2} = publish(Msg, MsgPropsFun1(MsgProps),
true, false, State1),
State2;
({IsPersistent, MsgId, MsgProps}, State1) ->
#vqstate { msg_store_clients = MSCState } = State1,
{{ok, Msg = #basic_message{}}, MSCState1} =
msg_store_read(MSCState, IsPersistent, MsgId),
State2 = State1 #vqstate { msg_store_clients = MSCState1 },
{_SeqId, State3} = publish(Msg, MsgPropsFun1(MsgProps),
true, true, State2),
State3
end,
AckTags, State),
{MsgIds, a(reduce_memory_use(State1))}.
len(#vqstate { len = Len }) -> Len.
is_empty(State) -> 0 == len(State).
set_ram_duration_target(
DurationTarget, State = #vqstate {
rates = #rates { avg_egress = AvgEgressRate,
avg_ingress = AvgIngressRate },
ack_rates = #rates { avg_egress = AvgAckEgressRate,
avg_ingress = AvgAckIngressRate },
target_ram_count = TargetRamCount }) ->
Rate =
AvgEgressRate + AvgIngressRate + AvgAckEgressRate + AvgAckIngressRate,
TargetRamCount1 =
case DurationTarget of
infinity -> infinity;
_ -> trunc(DurationTarget * Rate) %% msgs = sec * msgs/sec
end,
State1 = State #vqstate { target_ram_count = TargetRamCount1 },
a(case TargetRamCount1 == infinity orelse
(TargetRamCount =/= infinity andalso
TargetRamCount1 >= TargetRamCount) of
true -> State1;
false -> reduce_memory_use(State1)
end).
ram_duration(State = #vqstate {
rates = #rates { timestamp = Timestamp,
egress = Egress,
ingress = Ingress } = Rates,
ack_rates = #rates { timestamp = AckTimestamp,
egress = AckEgress,
ingress = AckIngress } = ARates,
in_counter = InCount,
out_counter = OutCount,
ack_in_counter = AckInCount,
ack_out_counter = AckOutCount,
ram_msg_count = RamMsgCount,
ram_msg_count_prev = RamMsgCountPrev,
ram_ack_index = RamAckIndex,
ram_ack_count_prev = RamAckCountPrev }) ->
Now = now(),
{AvgEgressRate, Egress1} = update_rate(Now, Timestamp, OutCount, Egress),
{AvgIngressRate, Ingress1} = update_rate(Now, Timestamp, InCount, Ingress),
{AvgAckEgressRate, AckEgress1} =
update_rate(Now, AckTimestamp, AckOutCount, AckEgress),
{AvgAckIngressRate, AckIngress1} =
update_rate(Now, AckTimestamp, AckInCount, AckIngress),
RamAckCount = gb_trees:size(RamAckIndex),
Duration = %% msgs+acks / (msgs+acks/sec) == sec
case (AvgEgressRate == 0 andalso AvgIngressRate == 0 andalso
AvgAckEgressRate == 0 andalso AvgAckIngressRate == 0) of
true -> infinity;
false -> (RamMsgCountPrev + RamMsgCount +
RamAckCount + RamAckCountPrev) /
(4 * (AvgEgressRate + AvgIngressRate +
AvgAckEgressRate + AvgAckIngressRate))
end,
{Duration, State #vqstate {
rates = Rates #rates {
egress = Egress1,
ingress = Ingress1,
avg_egress = AvgEgressRate,
avg_ingress = AvgIngressRate,
timestamp = Now },
ack_rates = ARates #rates {
egress = AckEgress1,
ingress = AckIngress1,
avg_egress = AvgAckEgressRate,
avg_ingress = AvgAckIngressRate,
timestamp = Now },
in_counter = 0,
out_counter = 0,
ack_in_counter = 0,
ack_out_counter = 0,
ram_msg_count_prev = RamMsgCount,
ram_ack_count_prev = RamAckCount }}.
needs_idle_timeout(State = #vqstate { on_sync = OnSync }) ->
case {OnSync, needs_index_sync(State)} of
{?BLANK_SYNC, false} ->
{Res, _State} = reduce_memory_use(
fun (_Quota, State1) -> {0, State1} end,
fun (_Quota, State1) -> State1 end,
fun (State1) -> State1 end,
fun (_Quota, State1) -> {0, State1} end,
State),
Res;
_ ->
true
end.
idle_timeout(State) ->
a(reduce_memory_use(confirm_commit_index(tx_commit_index(State)))).
handle_pre_hibernate(State = #vqstate { index_state = IndexState }) ->
State #vqstate { index_state = rabbit_queue_index:flush(IndexState) }.
status(#vqstate {
q1 = Q1, q2 = Q2, delta = Delta, q3 = Q3, q4 = Q4,
len = Len,
pending_ack = PA,
ram_ack_index = RAI,
on_sync = #sync { funs = From },
target_ram_count = TargetRamCount,
ram_msg_count = RamMsgCount,
ram_index_count = RamIndexCount,
next_seq_id = NextSeqId,
persistent_count = PersistentCount,
rates = #rates { avg_egress = AvgEgressRate,
avg_ingress = AvgIngressRate },
ack_rates = #rates { avg_egress = AvgAckEgressRate,
avg_ingress = AvgAckIngressRate } }) ->
[ {q1 , queue:len(Q1)},
{q2 , bpqueue:len(Q2)},
{delta , Delta},
{q3 , bpqueue:len(Q3)},
{q4 , queue:len(Q4)},
{len , Len},
{pending_acks , dict:size(PA)},
{outstanding_txns , length(From)},
{target_ram_count , TargetRamCount},
{ram_msg_count , RamMsgCount},
{ram_ack_count , gb_trees:size(RAI)},
{ram_index_count , RamIndexCount},
{next_seq_id , NextSeqId},
{persistent_count , PersistentCount},
{avg_ingress_rate , AvgIngressRate},
{avg_egress_rate , AvgEgressRate},
{avg_ack_ingress_rate, AvgAckIngressRate},
{avg_ack_egress_rate , AvgAckEgressRate} ].
invoke(?MODULE, Fun, State) ->
Fun(?MODULE, State).
is_duplicate(_Txn, _Msg, State) -> {false, State}.
discard(_Msg, _ChPid, State) -> State.
%%----------------------------------------------------------------------------
%% Minor helpers
%%----------------------------------------------------------------------------
a(State = #vqstate { q1 = Q1, q2 = Q2, delta = Delta, q3 = Q3, q4 = Q4,
len = Len,
persistent_count = PersistentCount,
ram_msg_count = RamMsgCount,
ram_index_count = RamIndexCount }) ->
E1 = queue:is_empty(Q1),
E2 = bpqueue:is_empty(Q2),
ED = Delta#delta.count == 0,
E3 = bpqueue:is_empty(Q3),
E4 = queue:is_empty(Q4),
LZ = Len == 0,
true = E1 or not E3,
true = E2 or not ED,
true = ED or not E3,
true = LZ == (E3 and E4),
true = Len >= 0,
true = PersistentCount >= 0,
true = RamMsgCount >= 0,
true = RamIndexCount >= 0,
State.
m(MsgStatus = #msg_status { msg = Msg,
is_persistent = IsPersistent,
msg_on_disk = MsgOnDisk,
index_on_disk = IndexOnDisk }) ->
true = (not IsPersistent) or IndexOnDisk,
true = (not IndexOnDisk) or MsgOnDisk,
true = (Msg =/= undefined) or MsgOnDisk,
MsgStatus.
one_if(true ) -> 1;
one_if(false) -> 0.
cons_if(true, E, L) -> [E | L];
cons_if(false, _E, L) -> L.
gb_sets_maybe_insert(false, _Val, Set) -> Set;
%% when requeueing, we re-add a msg_id to the unconfirmed set
gb_sets_maybe_insert(true, Val, Set) -> gb_sets:add(Val, Set).
msg_status(IsPersistent, SeqId, Msg = #basic_message { id = MsgId },
MsgProps) ->
#msg_status { seq_id = SeqId, msg_id = MsgId, msg = Msg,
is_persistent = IsPersistent, is_delivered = false,
msg_on_disk = false, index_on_disk = false,
msg_props = MsgProps }.
with_msg_store_state({MSCStateP, MSCStateT}, true, Fun) ->
{Result, MSCStateP1} = Fun(MSCStateP),
{Result, {MSCStateP1, MSCStateT}};
with_msg_store_state({MSCStateP, MSCStateT}, false, Fun) ->
{Result, MSCStateT1} = Fun(MSCStateT),
{Result, {MSCStateP, MSCStateT1}}.
with_immutable_msg_store_state(MSCState, IsPersistent, Fun) ->
{Res, MSCState} = with_msg_store_state(MSCState, IsPersistent,
fun (MSCState1) ->
{Fun(MSCState1), MSCState1}
end),
Res.
msg_store_client_init(MsgStore, MsgOnDiskFun, Callback) ->
msg_store_client_init(MsgStore, rabbit_guid:guid(), MsgOnDiskFun, Callback).
msg_store_client_init(MsgStore, Ref, MsgOnDiskFun, Callback) ->
CloseFDsFun = msg_store_close_fds_fun(MsgStore =:= ?PERSISTENT_MSG_STORE),
rabbit_msg_store:client_init(MsgStore, Ref, MsgOnDiskFun,
fun () -> Callback(?MODULE, CloseFDsFun) end).
msg_store_write(MSCState, IsPersistent, MsgId, Msg) ->
with_immutable_msg_store_state(
MSCState, IsPersistent,
fun (MSCState1) -> rabbit_msg_store:write(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).
msg_store_remove(MSCState, IsPersistent, MsgIds) ->
with_immutable_msg_store_state(
MSCState, IsPersistent,
fun (MCSState1) -> rabbit_msg_store:remove(MsgIds, MCSState1) end).
msg_store_sync(MSCState, IsPersistent, MsgIds, Fun) ->
with_immutable_msg_store_state(
MSCState, IsPersistent,
fun (MSCState1) -> rabbit_msg_store:sync(MsgIds, Fun, MSCState1) end).
msg_store_close_fds(MSCState, IsPersistent) ->
with_msg_store_state(
MSCState, IsPersistent,
fun (MSCState1) -> rabbit_msg_store:close_all_indicated(MSCState1) end).
msg_store_close_fds_fun(IsPersistent) ->
fun (?MODULE, State = #vqstate { msg_store_clients = MSCState }) ->
{ok, MSCState1} = msg_store_close_fds(MSCState, IsPersistent),
State #vqstate { msg_store_clients = MSCState1 }
end.
maybe_write_delivered(false, _SeqId, IndexState) ->
IndexState;
maybe_write_delivered(true, SeqId, IndexState) ->
rabbit_queue_index:deliver([SeqId], IndexState).
lookup_tx(Txn) -> case get({txn, Txn}) of
undefined -> #tx { pending_messages = [],
pending_acks = [] };
V -> V
end.
store_tx(Txn, Tx) -> put({txn, Txn}, Tx).
erase_tx(Txn) -> erase({txn, Txn}).
persistent_msg_ids(Pubs) ->
[MsgId || {#basic_message { id = MsgId,
is_persistent = true }, _MsgProps} <- Pubs].
betas_from_index_entries(List, TransientThreshold, IndexState) ->
{Filtered, Delivers, Acks} =
lists:foldr(
fun ({MsgId, SeqId, MsgProps, IsPersistent, IsDelivered},
{Filtered1, Delivers1, Acks1}) ->
case SeqId < TransientThreshold andalso not IsPersistent of
true -> {Filtered1,
cons_if(not IsDelivered, SeqId, Delivers1),
[SeqId | Acks1]};
false -> {[m(#msg_status { msg = undefined,
msg_id = MsgId,
seq_id = SeqId,
is_persistent = IsPersistent,
is_delivered = IsDelivered,
msg_on_disk = true,
index_on_disk = true,
msg_props = MsgProps
}) | Filtered1],
Delivers1,
Acks1}
end
end, {[], [], []}, List),
{bpqueue:from_list([{true, Filtered}]),
rabbit_queue_index:ack(Acks,
rabbit_queue_index:deliver(Delivers, IndexState))}.
%% the first arg is the older delta
combine_deltas(?BLANK_DELTA_PATTERN(X), ?BLANK_DELTA_PATTERN(Y)) ->
?BLANK_DELTA;
combine_deltas(?BLANK_DELTA_PATTERN(X), #delta { start_seq_id = Start,
count = Count,
end_seq_id = End } = B) ->
true = Start + Count =< End, %% ASSERTION
B;
combine_deltas(#delta { start_seq_id = Start,
count = Count,
end_seq_id = End } = A, ?BLANK_DELTA_PATTERN(Y)) ->
true = Start + Count =< End, %% ASSERTION
A;
combine_deltas(#delta { start_seq_id = StartLow,
count = CountLow,
end_seq_id = EndLow },
#delta { start_seq_id = StartHigh,
count = CountHigh,
end_seq_id = EndHigh }) ->
Count = CountLow + CountHigh,
true = (StartLow =< StartHigh) %% ASSERTIONS
andalso ((StartLow + CountLow) =< EndLow)
andalso ((StartHigh + CountHigh) =< EndHigh)
andalso ((StartLow + Count) =< EndHigh),
#delta { start_seq_id = StartLow, count = Count, end_seq_id = EndHigh }.
beta_fold(Fun, Init, Q) ->
bpqueue:foldr(fun (_Prefix, Value, Acc) -> Fun(Value, Acc) end, Init, Q).
update_rate(Now, Then, Count, {OThen, OCount}) ->
%% avg over the current period and the previous
{1000000.0 * (Count + OCount) / timer:now_diff(Now, OThen), {Then, Count}}.
%%----------------------------------------------------------------------------
%% Internal major helpers for Public API
%%----------------------------------------------------------------------------
init(IsDurable, IndexState, DeltaCount, Terms,
AsyncCallback, SyncCallback, PersistentClient, TransientClient) ->
{LowSeqId, NextSeqId, IndexState1} = rabbit_queue_index:bounds(IndexState),
DeltaCount1 = proplists:get_value(persistent_count, Terms, DeltaCount),
Delta = case DeltaCount1 == 0 andalso DeltaCount /= undefined of
true -> ?BLANK_DELTA;
false -> #delta { start_seq_id = LowSeqId,
count = DeltaCount1,
end_seq_id = NextSeqId }
end,
Now = now(),
State = #vqstate {
q1 = queue:new(),
q2 = bpqueue:new(),
delta = Delta,
q3 = bpqueue:new(),
q4 = queue:new(),
next_seq_id = NextSeqId,
pending_ack = dict:new(),
ram_ack_index = gb_trees:empty(),
index_state = IndexState1,
msg_store_clients = {PersistentClient, TransientClient},
on_sync = ?BLANK_SYNC,
durable = IsDurable,
transient_threshold = NextSeqId,
async_callback = AsyncCallback,
sync_callback = SyncCallback,
len = DeltaCount1,
persistent_count = DeltaCount1,
target_ram_count = infinity,
ram_msg_count = 0,
ram_msg_count_prev = 0,
ram_ack_count_prev = 0,
ram_index_count = 0,
out_counter = 0,
in_counter = 0,
rates = blank_rate(Now, DeltaCount1),
msgs_on_disk = gb_sets:new(),
msg_indices_on_disk = gb_sets:new(),
unconfirmed = gb_sets:new(),
confirmed = gb_sets:new(),
ack_out_counter = 0,
ack_in_counter = 0,
ack_rates = blank_rate(Now, 0) },
a(maybe_deltas_to_betas(State)).
blank_rate(Timestamp, IngressLength) ->
#rates { egress = {Timestamp, 0},
ingress = {Timestamp, IngressLength},
avg_egress = 0.0,
avg_ingress = 0.0,
timestamp = Timestamp }.
msg_store_callback(PersistentMsgIds, Pubs, AckTags, Fun, MsgPropsFun,
AsyncCallback, SyncCallback) ->
case SyncCallback(?MODULE,
fun (?MODULE, StateN) ->
tx_commit_post_msg_store(true, Pubs, AckTags,
Fun, MsgPropsFun, StateN)
end) of
ok -> ok;
error -> remove_persistent_messages(PersistentMsgIds, AsyncCallback)
end.
remove_persistent_messages(MsgIds, AsyncCallback) ->
PersistentClient = msg_store_client_init(?PERSISTENT_MSG_STORE,
undefined, AsyncCallback),
ok = rabbit_msg_store:remove(MsgIds, PersistentClient),
rabbit_msg_store:client_delete_and_terminate(PersistentClient).
tx_commit_post_msg_store(HasPersistentPubs, Pubs, AckTags, Fun, MsgPropsFun,
State = #vqstate {
on_sync = OnSync = #sync {
acks_persistent = SPAcks,
acks_all = SAcks,
pubs = SPubs,
funs = SFuns },
pending_ack = PA,
durable = IsDurable }) ->
PersistentAcks =
case IsDurable of
true -> [AckTag || AckTag <- AckTags,
case dict:fetch(AckTag, PA) of
#msg_status {} ->
false;
{IsPersistent, _MsgId, _MsgProps} ->
IsPersistent
end];
false -> []
end,
case IsDurable andalso (HasPersistentPubs orelse PersistentAcks =/= []) of
true -> State #vqstate {
on_sync = #sync {
acks_persistent = [PersistentAcks | SPAcks],
acks_all = [AckTags | SAcks],
pubs = [{MsgPropsFun, Pubs} | SPubs],
funs = [Fun | SFuns] }};
false -> State1 = tx_commit_index(
State #vqstate {
on_sync = #sync {
acks_persistent = [],
acks_all = [AckTags],
pubs = [{MsgPropsFun, Pubs}],
funs = [Fun] } }),
State1 #vqstate { on_sync = OnSync }
end.
tx_commit_index(State = #vqstate { on_sync = ?BLANK_SYNC }) ->
State;
tx_commit_index(State = #vqstate { on_sync = #sync {
acks_persistent = SPAcks,
acks_all = SAcks,
pubs = SPubs,
funs = SFuns },
durable = IsDurable }) ->
PAcks = lists:append(SPAcks),
Acks = lists:append(SAcks),
Pubs = [{Msg, Fun(MsgProps)} || {Fun, PubsN} <- lists:reverse(SPubs),
{Msg, MsgProps} <- lists:reverse(PubsN)],
{_MsgIds, State1} = ack(Acks, State),
{SeqIds, State2 = #vqstate { index_state = IndexState }} =
lists:foldl(
fun ({Msg = #basic_message { is_persistent = IsPersistent },
MsgProps},
{SeqIdsAcc, State3}) ->
IsPersistent1 = IsDurable andalso IsPersistent,
{SeqId, State4} =
publish(Msg, MsgProps, false, IsPersistent1, State3),
{cons_if(IsPersistent1, SeqId, SeqIdsAcc), State4}
end, {PAcks, State1}, Pubs),
IndexState1 = rabbit_queue_index:sync(SeqIds, IndexState),
[ Fun() || Fun <- lists:reverse(SFuns) ],
reduce_memory_use(
State2 #vqstate { index_state = IndexState1, on_sync = ?BLANK_SYNC }).
purge_betas_and_deltas(LensByStore,
State = #vqstate { q3 = Q3,
index_state = IndexState,
msg_store_clients = MSCState }) ->
case bpqueue:is_empty(Q3) of
true -> {LensByStore, State};
false -> {LensByStore1, IndexState1} =
remove_queue_entries(fun beta_fold/3, Q3,
LensByStore, IndexState, MSCState),
purge_betas_and_deltas(LensByStore1,
maybe_deltas_to_betas(
State #vqstate {
q3 = bpqueue:new(),
index_state = IndexState1 }))
end.
remove_queue_entries(Fold, Q, LensByStore, IndexState, MSCState) ->
{MsgIdsByStore, Delivers, Acks} =
Fold(fun remove_queue_entries1/2, {orddict:new(), [], []}, Q),
ok = orddict:fold(fun (IsPersistent, MsgIds, ok) ->
msg_store_remove(MSCState, IsPersistent, MsgIds)
end, ok, MsgIdsByStore),
{sum_msg_ids_by_store_to_len(LensByStore, MsgIdsByStore),
rabbit_queue_index:ack(Acks,
rabbit_queue_index:deliver(Delivers, IndexState))}.
remove_queue_entries1(
#msg_status { msg_id = MsgId, seq_id = SeqId,
is_delivered = IsDelivered, msg_on_disk = MsgOnDisk,
index_on_disk = IndexOnDisk, is_persistent = IsPersistent },
{MsgIdsByStore, Delivers, Acks}) ->
{case MsgOnDisk of
true -> rabbit_misc:orddict_cons(IsPersistent, MsgId, MsgIdsByStore);
false -> MsgIdsByStore
end,
cons_if(IndexOnDisk andalso not IsDelivered, SeqId, Delivers),
cons_if(IndexOnDisk, SeqId, Acks)}.
sum_msg_ids_by_store_to_len(LensByStore, MsgIdsByStore) ->
orddict:fold(
fun (IsPersistent, MsgIds, LensByStore1) ->
orddict:update_counter(IsPersistent, length(MsgIds), LensByStore1)
end, LensByStore, MsgIdsByStore).
%%----------------------------------------------------------------------------
%% Internal gubbins for publishing
%%----------------------------------------------------------------------------
publish(Msg = #basic_message { is_persistent = IsPersistent, id = MsgId },
MsgProps = #message_properties { needs_confirming = NeedsConfirming },
IsDelivered, MsgOnDisk,
State = #vqstate { q1 = Q1, q3 = Q3, q4 = Q4,
next_seq_id = SeqId,
len = Len,
in_counter = InCount,
persistent_count = PCount,
durable = IsDurable,
ram_msg_count = RamMsgCount,
unconfirmed = UC }) ->
IsPersistent1 = IsDurable andalso IsPersistent,
MsgStatus = (msg_status(IsPersistent1, SeqId, Msg, MsgProps))
#msg_status { is_delivered = IsDelivered, msg_on_disk = MsgOnDisk},
{MsgStatus1, State1} = maybe_write_to_disk(false, false, MsgStatus, State),
State2 = case bpqueue:is_empty(Q3) of
false -> State1 #vqstate { q1 = queue:in(m(MsgStatus1), Q1) };
true -> State1 #vqstate { q4 = queue:in(m(MsgStatus1), Q4) }
end,
PCount1 = PCount + one_if(IsPersistent1),
UC1 = gb_sets_maybe_insert(NeedsConfirming, MsgId, UC),
{SeqId, State2 #vqstate { next_seq_id = SeqId + 1,
len = Len + 1,
in_counter = InCount + 1,
persistent_count = PCount1,
ram_msg_count = RamMsgCount + 1,
unconfirmed = UC1 }}.
maybe_write_msg_to_disk(_Force, MsgStatus = #msg_status {
msg_on_disk = true }, _MSCState) ->
MsgStatus;
maybe_write_msg_to_disk(Force, MsgStatus = #msg_status {
msg = Msg, msg_id = MsgId,
is_persistent = IsPersistent }, MSCState)
when Force orelse IsPersistent ->
Msg1 = Msg #basic_message {
%% don't persist any recoverable decoded properties
content = rabbit_binary_parser:clear_decoded_content(
Msg #basic_message.content)},
ok = msg_store_write(MSCState, IsPersistent, MsgId, Msg1),
MsgStatus #msg_status { msg_on_disk = true };
maybe_write_msg_to_disk(_Force, MsgStatus, _MSCState) ->
MsgStatus.
maybe_write_index_to_disk(_Force, MsgStatus = #msg_status {
index_on_disk = true }, IndexState) ->
true = MsgStatus #msg_status.msg_on_disk, %% ASSERTION
{MsgStatus, IndexState};
maybe_write_index_to_disk(Force, MsgStatus = #msg_status {
msg_id = MsgId,
seq_id = SeqId,
is_persistent = IsPersistent,
is_delivered = IsDelivered,
msg_props = MsgProps}, IndexState)
when Force orelse IsPersistent ->
true = MsgStatus #msg_status.msg_on_disk, %% ASSERTION
IndexState1 = rabbit_queue_index:publish(
MsgId, SeqId, MsgProps, IsPersistent, IndexState),
{MsgStatus #msg_status { index_on_disk = true },
maybe_write_delivered(IsDelivered, SeqId, IndexState1)};
maybe_write_index_to_disk(_Force, MsgStatus, IndexState) ->
{MsgStatus, IndexState}.
maybe_write_to_disk(ForceMsg, ForceIndex, MsgStatus,
State = #vqstate { index_state = IndexState,
msg_store_clients = MSCState }) ->
MsgStatus1 = maybe_write_msg_to_disk(ForceMsg, MsgStatus, MSCState),
{MsgStatus2, IndexState1} =
maybe_write_index_to_disk(ForceIndex, MsgStatus1, IndexState),
{MsgStatus2, State #vqstate { index_state = IndexState1 }}.
%%----------------------------------------------------------------------------
%% Internal gubbins for acks
%%----------------------------------------------------------------------------
record_pending_ack(#msg_status { seq_id = SeqId,
msg_id = MsgId,
is_persistent = IsPersistent,
msg_on_disk = MsgOnDisk,
msg_props = MsgProps } = MsgStatus,
State = #vqstate { pending_ack = PA,
ram_ack_index = RAI,
ack_in_counter = AckInCount}) ->
{AckEntry, RAI1} =
case MsgOnDisk of
true -> {{IsPersistent, MsgId, MsgProps}, RAI};
false -> {MsgStatus, gb_trees:insert(SeqId, MsgId, RAI)}
end,
PA1 = dict:store(SeqId, AckEntry, PA),
State #vqstate { pending_ack = PA1,
ram_ack_index = RAI1,
ack_in_counter = AckInCount + 1}.
remove_pending_ack(KeepPersistent,
State = #vqstate { pending_ack = PA,
index_state = IndexState,
msg_store_clients = MSCState }) ->
{PersistentSeqIds, MsgIdsByStore, _AllMsgIds} =
dict:fold(fun accumulate_ack/3, accumulate_ack_init(), PA),
State1 = State #vqstate { pending_ack = dict:new(),
ram_ack_index = gb_trees:empty() },
case KeepPersistent of
true -> case orddict:find(false, MsgIdsByStore) of
error -> State1;
{ok, MsgIds} -> ok = msg_store_remove(MSCState, false,
MsgIds),
State1
end;
false -> IndexState1 =
rabbit_queue_index:ack(PersistentSeqIds, IndexState),
[ok = msg_store_remove(MSCState, IsPersistent, MsgIds)
|| {IsPersistent, MsgIds} <- orddict:to_list(MsgIdsByStore)],
State1 #vqstate { index_state = IndexState1 }
end.
ack(_MsgStoreFun, _Fun, [], State) ->
{[], State};
ack(MsgStoreFun, Fun, AckTags, State) ->
{{PersistentSeqIds, MsgIdsByStore, AllMsgIds},
State1 = #vqstate { index_state = IndexState,
msg_store_clients = MSCState,
persistent_count = PCount,
ack_out_counter = AckOutCount }} =
lists:foldl(
fun (SeqId, {Acc, State2 = #vqstate { pending_ack = PA,
ram_ack_index = RAI }}) ->
AckEntry = dict:fetch(SeqId, PA),
{accumulate_ack(SeqId, AckEntry, Acc),
Fun(AckEntry, State2 #vqstate {
pending_ack = dict:erase(SeqId, PA),
ram_ack_index =
gb_trees:delete_any(SeqId, RAI)})}
end, {accumulate_ack_init(), State}, AckTags),
IndexState1 = rabbit_queue_index:ack(PersistentSeqIds, IndexState),
[ok = MsgStoreFun(MSCState, IsPersistent, MsgIds)
|| {IsPersistent, MsgIds} <- orddict:to_list(MsgIdsByStore)],
PCount1 = PCount - find_persistent_count(sum_msg_ids_by_store_to_len(
orddict:new(), MsgIdsByStore)),
{lists:reverse(AllMsgIds),
State1 #vqstate { index_state = IndexState1,
persistent_count = PCount1,
ack_out_counter = AckOutCount + length(AckTags) }}.
accumulate_ack_init() -> {[], orddict:new(), []}.
accumulate_ack(_SeqId, #msg_status { is_persistent = false, %% ASSERTIONS
msg_on_disk = false,
index_on_disk = false,
msg_id = MsgId },
{PersistentSeqIdsAcc, MsgIdsByStore, AllMsgIds}) ->
{PersistentSeqIdsAcc, MsgIdsByStore, [MsgId | AllMsgIds]};
accumulate_ack(SeqId, {IsPersistent, MsgId, _MsgProps},
{PersistentSeqIdsAcc, MsgIdsByStore, AllMsgIds}) ->
{cons_if(IsPersistent, SeqId, PersistentSeqIdsAcc),
rabbit_misc:orddict_cons(IsPersistent, MsgId, MsgIdsByStore),
[MsgId | AllMsgIds]}.
find_persistent_count(LensByStore) ->
case orddict:find(true, LensByStore) of
error -> 0;
{ok, Len} -> Len
end.
%%----------------------------------------------------------------------------
%% 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 }) ->
%% If UC is empty then by definition, MIOD and MOD are also empty
%% and there's nothing that can be pending a sync.
%% If UC is not empty, then we want to find is_empty(UC - MIOD),
%% but the subtraction can be expensive. Thus instead, we test to
%% see if UC is a subset of MIOD. This can only be the case if
%% MIOD == UC, which would indicate that every message in UC is
%% also in MIOD and is thus _all_ pending on a msg_store sync, not
%% on a qi sync. Thus the negation of this is sufficient. Because
%% is_subset is short circuiting, this is more efficient than the
%% subtraction.
not (gb_sets:is_empty(UC) orelse gb_sets:is_subset(UC, MIOD)).
blind_confirm(Callback, MsgIdSet) ->
Callback(?MODULE,
fun (?MODULE, State) -> record_confirms(MsgIdSet, State) end).
msgs_written_to_disk(Callback, MsgIdSet, removed) ->
blind_confirm(Callback, MsgIdSet);
msgs_written_to_disk(Callback, MsgIdSet, written) ->
Callback(?MODULE,
fun (?MODULE, State = #vqstate { msgs_on_disk = MOD,
msg_indices_on_disk = MIOD,
unconfirmed = UC }) ->
Confirmed = gb_sets:intersection(UC, MsgIdSet),
record_confirms(gb_sets:intersection(MsgIdSet, MIOD),
State #vqstate {
msgs_on_disk =
gb_sets:union(MOD, Confirmed) })
end).
msg_indices_written_to_disk(Callback, MsgIdSet) ->
Callback(?MODULE,
fun (?MODULE, State = #vqstate { msgs_on_disk = MOD,
msg_indices_on_disk = MIOD,
unconfirmed = UC }) ->
Confirmed = gb_sets:intersection(UC, MsgIdSet),
record_confirms(gb_sets:intersection(MsgIdSet, MOD),
State #vqstate {
msg_indices_on_disk =
gb_sets:union(MIOD, Confirmed) })
end).
%%----------------------------------------------------------------------------
%% Phase changes
%%----------------------------------------------------------------------------
%% Determine whether a reduction in memory use is necessary, and call
%% functions to perform the required phase changes. The function can
%% also be used to just do the former, by passing in dummy phase
%% change functions.
%%
%% The function does not report on any needed beta->delta conversions,
%% though the conversion function for that is called as necessary. The
%% reason is twofold. Firstly, this is safe because the conversion is
%% only ever necessary just after a transition to a
%% target_ram_count of zero or after an incremental alpha->beta
%% conversion. In the former case the conversion is performed straight
%% away (i.e. any betas present at the time are converted to deltas),
%% and in the latter case the need for a conversion is flagged up
%% anyway. Secondly, this is necessary because we do not have a
%% precise and cheap predicate for determining whether a beta->delta
%% conversion is necessary - due to the complexities of retaining up
%% one segment's worth of messages in q3 - and thus would risk
%% perpetually reporting the need for a conversion when no such
%% conversion is needed. That in turn could cause an infinite loop.
reduce_memory_use(_AlphaBetaFun, _BetaGammaFun, _BetaDeltaFun, _AckFun,
State = #vqstate {target_ram_count = infinity}) ->
{false, State};
reduce_memory_use(AlphaBetaFun, BetaGammaFun, BetaDeltaFun, AckFun,
State = #vqstate {
ram_ack_index = RamAckIndex,
ram_msg_count = RamMsgCount,
target_ram_count = TargetRamCount,
rates = #rates { avg_ingress = AvgIngress,
avg_egress = AvgEgress },
ack_rates = #rates { avg_ingress = AvgAckIngress,
avg_egress = AvgAckEgress }
}) ->
{Reduce, State1} =
case chunk_size(RamMsgCount + gb_trees:size(RamAckIndex),
TargetRamCount) of
0 -> {false, State};
%% Reduce memory of pending acks and alphas. The order is
%% determined based on which is growing faster. Whichever
%% comes second may very well get a quota of 0 if the
%% first manages to push out the max number of messages.
S1 -> {_, State2} =
lists:foldl(fun (ReduceFun, {QuotaN, StateN}) ->
ReduceFun(QuotaN, StateN)
end,
{S1, State},
case (AvgAckIngress - AvgAckEgress) >
(AvgIngress - AvgEgress) of
true -> [AckFun, AlphaBetaFun];
false -> [AlphaBetaFun, AckFun]
end),
{true, State2}
end,
case State1 #vqstate.target_ram_count of
0 -> {Reduce, BetaDeltaFun(State1)};
_ -> case chunk_size(State1 #vqstate.ram_index_count,
permitted_ram_index_count(State1)) of
?IO_BATCH_SIZE = S2 -> {true, BetaGammaFun(S2, State1)};
_ -> {Reduce, State1}
end
end.
limit_ram_acks(0, State) ->
{0, State};
limit_ram_acks(Quota, State = #vqstate { pending_ack = PA,
ram_ack_index = RAI }) ->
case gb_trees:is_empty(RAI) of
true ->
{Quota, State};
false ->
{SeqId, MsgId, RAI1} = gb_trees:take_largest(RAI),
MsgStatus = #msg_status {
msg_id = MsgId, %% ASSERTION
is_persistent = false, %% ASSERTION
msg_props = MsgProps } = dict:fetch(SeqId, PA),
{_, State1} = maybe_write_to_disk(true, false, MsgStatus, State),
PA1 = dict:store(SeqId, {false, MsgId, MsgProps}, PA),
limit_ram_acks(Quota - 1,
State1 #vqstate { pending_ack = PA1,
ram_ack_index = RAI1 })
end.
reduce_memory_use(State) ->
{_, State1} = reduce_memory_use(fun push_alphas_to_betas/2,
fun limit_ram_index/2,
fun push_betas_to_deltas/1,
fun limit_ram_acks/2,
State),
State1.
limit_ram_index(Quota, State = #vqstate { q2 = Q2, q3 = Q3,
index_state = IndexState,
ram_index_count = RamIndexCount }) ->
{Q2a, {Quota1, IndexState1}} = limit_ram_index(
fun bpqueue:map_fold_filter_r/4,
Q2, {Quota, IndexState}),
%% TODO: we shouldn't be writing index entries for messages that
%% can never end up in delta due them residing in the only segment
%% held by q3.
{Q3a, {Quota2, IndexState2}} = limit_ram_index(
fun bpqueue:map_fold_filter_r/4,
Q3, {Quota1, IndexState1}),
State #vqstate { q2 = Q2a, q3 = Q3a,
index_state = IndexState2,
ram_index_count = RamIndexCount - (Quota - Quota2) }.
limit_ram_index(_MapFoldFilterFun, Q, {0, IndexState}) ->
{Q, {0, IndexState}};
limit_ram_index(MapFoldFilterFun, Q, {Quota, IndexState}) ->
MapFoldFilterFun(
fun erlang:'not'/1,
fun (MsgStatus, {0, _IndexStateN}) ->
false = MsgStatus #msg_status.index_on_disk, %% ASSERTION
stop;
(MsgStatus, {N, IndexStateN}) when N > 0 ->
false = MsgStatus #msg_status.index_on_disk, %% ASSERTION
{MsgStatus1, IndexStateN1} =
maybe_write_index_to_disk(true, MsgStatus, IndexStateN),
{true, m(MsgStatus1), {N-1, IndexStateN1}}
end, {Quota, IndexState}, Q).
permitted_ram_index_count(#vqstate { len = 0 }) ->
infinity;
permitted_ram_index_count(#vqstate { len = Len,
q2 = Q2,
q3 = Q3,
delta = #delta { count = DeltaCount } }) ->
BetaLen = bpqueue:len(Q2) + bpqueue:len(Q3),
BetaLen - trunc(BetaLen * BetaLen / (Len - DeltaCount)).
chunk_size(Current, Permitted)
when Permitted =:= infinity orelse Permitted >= Current ->
0;
chunk_size(Current, Permitted) ->
lists:min([Current - Permitted, ?IO_BATCH_SIZE]).
fetch_from_q3(State = #vqstate {
q1 = Q1,
q2 = Q2,
delta = #delta { count = DeltaCount },
q3 = Q3,
q4 = Q4,
ram_index_count = RamIndexCount}) ->
case bpqueue:out(Q3) of
{empty, _Q3} ->
{empty, State};
{{value, IndexOnDisk, MsgStatus}, Q3a} ->
RamIndexCount1 = RamIndexCount - one_if(not IndexOnDisk),
true = RamIndexCount1 >= 0, %% ASSERTION
State1 = State #vqstate { q3 = Q3a,
ram_index_count = RamIndexCount1 },
State2 =
case {bpqueue:is_empty(Q3a), 0 == DeltaCount} of
{true, true} ->
%% q3 is now empty, it wasn't before; delta is
%% still empty. So q2 must be empty, and we
%% know q4 is empty otherwise we wouldn't be
%% loading from q3. As such, we can just set
%% q4 to Q1.
true = bpqueue:is_empty(Q2), %% ASSERTION
true = queue:is_empty(Q4), %% ASSERTION
State1 #vqstate { q1 = queue:new(),
q4 = Q1 };
{true, false} ->
maybe_deltas_to_betas(State1);
{false, _} ->
%% q3 still isn't empty, we've not touched
%% delta, so the invariants between q1, q2,
%% delta and q3 are maintained
State1
end,
{loaded, {MsgStatus, State2}}
end.
maybe_deltas_to_betas(State = #vqstate { delta = ?BLANK_DELTA_PATTERN(X) }) ->
State;
maybe_deltas_to_betas(State = #vqstate {
q2 = Q2,
delta = Delta,
q3 = Q3,
index_state = IndexState,
transient_threshold = TransientThreshold }) ->
#delta { start_seq_id = DeltaSeqId,
count = DeltaCount,
end_seq_id = DeltaSeqIdEnd } = Delta,
DeltaSeqId1 =
lists:min([rabbit_queue_index:next_segment_boundary(DeltaSeqId),
DeltaSeqIdEnd]),
{List, IndexState1} =
rabbit_queue_index:read(DeltaSeqId, DeltaSeqId1, IndexState),
{Q3a, IndexState2} =
betas_from_index_entries(List, TransientThreshold, IndexState1),
State1 = State #vqstate { index_state = IndexState2 },
case bpqueue:len(Q3a) of
0 ->
%% we ignored every message in the segment due to it being
%% transient and below the threshold
maybe_deltas_to_betas(
State1 #vqstate {
delta = Delta #delta { start_seq_id = DeltaSeqId1 }});
Q3aLen ->
Q3b = bpqueue:join(Q3, Q3a),
case DeltaCount - Q3aLen of
0 ->
%% delta is now empty, but it wasn't before, so
%% can now join q2 onto q3
State1 #vqstate { q2 = bpqueue:new(),
delta = ?BLANK_DELTA,
q3 = bpqueue:join(Q3b, Q2) };
N when N > 0 ->
Delta1 = #delta { start_seq_id = DeltaSeqId1,
count = N,
end_seq_id = DeltaSeqIdEnd },
State1 #vqstate { delta = Delta1,
q3 = Q3b }
end
end.
push_alphas_to_betas(Quota, State) ->
{Quota1, State1} = maybe_push_q1_to_betas(Quota, State),
{Quota2, State2} = maybe_push_q4_to_betas(Quota1, State1),
{Quota2, State2}.
maybe_push_q1_to_betas(Quota, State = #vqstate { q1 = Q1 }) ->
maybe_push_alphas_to_betas(
fun queue:out/1,
fun (MsgStatus = #msg_status { index_on_disk = IndexOnDisk },
Q1a, State1 = #vqstate { q3 = Q3, delta = #delta { count = 0 } }) ->
State1 #vqstate { q1 = Q1a,
q3 = bpqueue:in(IndexOnDisk, MsgStatus, Q3) };
(MsgStatus = #msg_status { index_on_disk = IndexOnDisk },
Q1a, State1 = #vqstate { q2 = Q2 }) ->
State1 #vqstate { q1 = Q1a,
q2 = bpqueue:in(IndexOnDisk, MsgStatus, Q2) }
end, Quota, Q1, State).
maybe_push_q4_to_betas(Quota, State = #vqstate { q4 = Q4 }) ->
maybe_push_alphas_to_betas(
fun queue:out_r/1,
fun (MsgStatus = #msg_status { index_on_disk = IndexOnDisk },
Q4a, State1 = #vqstate { q3 = Q3 }) ->
State1 #vqstate { q3 = bpqueue:in_r(IndexOnDisk, MsgStatus, Q3),
q4 = Q4a }
end, Quota, Q4, State).
maybe_push_alphas_to_betas(_Generator, _Consumer, Quota, _Q,
State = #vqstate {
ram_msg_count = RamMsgCount,
target_ram_count = TargetRamCount })
when Quota =:= 0 orelse
TargetRamCount =:= infinity orelse
TargetRamCount >= RamMsgCount ->
{Quota, State};
maybe_push_alphas_to_betas(Generator, Consumer, Quota, Q, State) ->
case Generator(Q) of
{empty, _Q} ->
{Quota, State};
{{value, MsgStatus}, Qa} ->
{MsgStatus1 = #msg_status { msg_on_disk = true,
index_on_disk = IndexOnDisk },
State1 = #vqstate { ram_msg_count = RamMsgCount,
ram_index_count = RamIndexCount }} =
maybe_write_to_disk(true, false, MsgStatus, State),
MsgStatus2 = m(MsgStatus1 #msg_status { msg = undefined }),
RamIndexCount1 = RamIndexCount + one_if(not IndexOnDisk),
State2 = State1 #vqstate { ram_msg_count = RamMsgCount - 1,
ram_index_count = RamIndexCount1 },
maybe_push_alphas_to_betas(Generator, Consumer, Quota - 1, Qa,
Consumer(MsgStatus2, Qa, State2))
end.
push_betas_to_deltas(State = #vqstate { q2 = Q2,
delta = Delta,
q3 = Q3,
index_state = IndexState,
ram_index_count = RamIndexCount }) ->
{Delta2, Q2a, RamIndexCount2, IndexState2} =
push_betas_to_deltas(fun (Q2MinSeqId) -> Q2MinSeqId end,
fun bpqueue:out/1, Q2,
RamIndexCount, IndexState),
{Delta3, Q3a, RamIndexCount3, IndexState3} =
push_betas_to_deltas(fun rabbit_queue_index:next_segment_boundary/1,
fun bpqueue:out_r/1, Q3,
RamIndexCount2, IndexState2),
Delta4 = combine_deltas(Delta3, combine_deltas(Delta, Delta2)),
State #vqstate { q2 = Q2a,
delta = Delta4,
q3 = Q3a,
index_state = IndexState3,
ram_index_count = RamIndexCount3 }.
push_betas_to_deltas(LimitFun, Generator, Q, RamIndexCount, IndexState) ->
case bpqueue:out(Q) of
{empty, _Q} ->
{?BLANK_DELTA, Q, RamIndexCount, IndexState};
{{value, _IndexOnDisk1, #msg_status { seq_id = MinSeqId }}, _Qa} ->
{{value, _IndexOnDisk2, #msg_status { seq_id = MaxSeqId }}, _Qb} =
bpqueue:out_r(Q),
Limit = LimitFun(MinSeqId),
case MaxSeqId < Limit of
true -> {?BLANK_DELTA, Q, RamIndexCount, IndexState};
false -> {Len, Qc, RamIndexCount1, IndexState1} =
push_betas_to_deltas(Generator, Limit, Q, 0,
RamIndexCount, IndexState),
{#delta { start_seq_id = Limit,
count = Len,
end_seq_id = MaxSeqId + 1 },
Qc, RamIndexCount1, IndexState1}
end
end.
push_betas_to_deltas(Generator, Limit, Q, Count, RamIndexCount, IndexState) ->
case Generator(Q) of
{empty, _Q} ->
{Count, Q, RamIndexCount, IndexState};
{{value, _IndexOnDisk, #msg_status { seq_id = SeqId }}, _Qa}
when SeqId < Limit ->
{Count, Q, RamIndexCount, IndexState};
{{value, IndexOnDisk, MsgStatus}, Qa} ->
{RamIndexCount1, IndexState1} =
case IndexOnDisk of
true -> {RamIndexCount, IndexState};
false -> {#msg_status { index_on_disk = true },
IndexState2} =
maybe_write_index_to_disk(true, MsgStatus,
IndexState),
{RamIndexCount - 1, IndexState2}
end,
push_betas_to_deltas(
Generator, Limit, Qa, Count + 1, RamIndexCount1, IndexState1)
end.
%%----------------------------------------------------------------------------
%% Upgrading
%%----------------------------------------------------------------------------
multiple_routing_keys() ->
transform_storage(
fun ({basic_message, ExchangeName, Routing_Key, Content,
MsgId, Persistent}) ->
{ok, {basic_message, ExchangeName, [Routing_Key], Content,
MsgId, Persistent}};
(_) -> {error, corrupt_message}
end),
ok.
%% Assumes message store is not running
transform_storage(TransformFun) ->
transform_store(?PERSISTENT_MSG_STORE, TransformFun),
transform_store(?TRANSIENT_MSG_STORE, TransformFun).
transform_store(Store, TransformFun) ->
rabbit_msg_store:force_recovery(rabbit_mnesia:dir(), Store),
rabbit_msg_store:transform_dir(rabbit_mnesia:dir(), Store, TransformFun).
|