refactors QI flushing

Author: videlalvaro

src/rabbit_variable_queue.erl

@@ -1828,20 +1828,13 @@ reduce_memory_use(State = #vqstate {
             State1
     end.
 
-limit_ram_acks(0, State = #vqstate{ index_state      = IndexState,
-                                    target_ram_count = TargetRamCount }) ->
-    IndexState1 = rabbit_queue_index:flush_pre_publish_cache(
-                    TargetRamCount, IndexState),
-    {0, State#vqstate{ index_state = IndexState1 }};
-limit_ram_acks(Quota, State = #vqstate { index_state      = IndexState,
-                                         target_ram_count = TargetRamCount,
-                                         ram_pending_ack  = RPA,
+limit_ram_acks(0, State) ->
+    {0, ui(State)};
+limit_ram_acks(Quota, State = #vqstate { ram_pending_ack  = RPA,
                                          disk_pending_ack = DPA }) ->
     case gb_trees:is_empty(RPA) of
         true ->
-            IndexState1 = rabbit_queue_index:flush_pre_publish_cache(
-                            TargetRamCount, IndexState),
-            {Quota, State#vqstate{index_state = IndexState1}};
+            {Quota, ui(State)};
         false ->
             {SeqId, MsgStatus, RPA1} = gb_trees:take_largest(RPA),
             {MsgStatus1, State1} =
@@ -1979,27 +1972,17 @@ push_alphas_to_betas(Quota, State) ->
 
 push_alphas_to_betas(_Generator, _Consumer, Quota, _Q,
                      State = #vqstate { ram_msg_count    = RamMsgCount,
-                                        index_state      = IndexState,
                                         target_ram_count = TargetRamCount })
   when Quota =:= 0 orelse
        TargetRamCount =:= infinity orelse
        TargetRamCount >= RamMsgCount ->
-    IndexState1 = rabbit_queue_index:flush_pre_publish_cache(
-                    TargetRamCount, IndexState),
-    {Quota, State#vqstate{index_state   = IndexState1}};
-push_alphas_to_betas(Generator, Consumer, Quota, Q,
-                     State = #vqstate{
-                                index_state      = IndexState,
-                                target_ram_count = TargetRamCount}) ->
+    {Quota, ui(State)};
+push_alphas_to_betas(Generator, Consumer, Quota, Q, State) ->
     case credit_flow:blocked() of
-        true  -> IndexState1 = rabbit_queue_index:flush_pre_publish_cache(
-                                 TargetRamCount, IndexState),
-                 {Quota, State#vqstate{index_state   = IndexState1}};
+        true  -> {Quota, ui(State)};
         false -> case Generator(Q) of
                      {empty, _Q} ->
-                         IndexState1 = rabbit_queue_index:flush_pre_publish_cache(
-                                         TargetRamCount, IndexState),
-                         {Quota, State#vqstate{index_state   = IndexState1}};
+                         {Quota, ui(State)};
                      {{value, MsgStatus}, Qa} ->
                          {MsgStatus1, State1} =
                              maybe_prepare_write_to_disk(true, false, MsgStatus,
@@ -2045,26 +2028,16 @@ push_betas_to_deltas(Generator, LimitFun, Q, PushState) ->
     end.
 
 push_betas_to_deltas1(_Generator, _Limit, Q,
-                      {0, Delta, State =
-                           #vqstate{index_state      = IndexState,
-                                    target_ram_count = TargetRamCount}}) ->
-    IndexState1 = rabbit_queue_index:flush_pre_publish_cache(
-                    TargetRamCount, IndexState),
-    {Q, {0, Delta, State#vqstate{index_state = IndexState1}}};
+                      {0, Delta, State}) ->
+    {Q, {0, Delta, ui(State)}};
 push_betas_to_deltas1(Generator, Limit, Q,
-                      {Quota, Delta, State =
-                           #vqstate{index_state      = IndexState,
-                                    target_ram_count = TargetRamCount}}) ->
+                      {Quota, Delta, State}) ->
     case Generator(Q) of
         {empty, _Q} ->
-            IndexState1 = rabbit_queue_index:flush_pre_publish_cache(
-                            TargetRamCount, IndexState),
-            {Q, {Quota, Delta, State#vqstate{index_state   = IndexState1}}};
+            {Q, {Quota, Delta, ui(State)}};
         {{value, #msg_status { seq_id = SeqId }}, _Qa}
           when SeqId < Limit ->
-            IndexState1 = rabbit_queue_index:flush_pre_publish_cache(
-                            TargetRamCount, IndexState),
-            {Q, {Quota, Delta, State#vqstate{index_state   = IndexState1}}};
+            {Q, {Quota, Delta, ui(State)}};
         {{value, MsgStatus = #msg_status { seq_id = SeqId }}, Qa} ->
             {#msg_status { index_on_disk = true }, State1} =
                 maybe_batch_write_index_to_disk(true, MsgStatus, State),
@@ -2074,6 +2047,13 @@ push_betas_to_deltas1(Generator, Limit, Q,
                                   {Quota - 1, Delta1, State2})
     end.
 
+%% Flushes queue index batch caches and updates queue index state.
+ui(#vqstate{index_state      = IndexState,
+            target_ram_count = TargetRamCount} = State) ->
+    IndexState1 = rabbit_queue_index:flush_pre_publish_cache(
+                    TargetRamCount, IndexState),
+    State#vqstate{index_state = IndexState1}.
+
 %%----------------------------------------------------------------------------
 %% Upgrading
 %%----------------------------------------------------------------------------