Max value policy. Update descriptions

Author: SimonUnge

deps/rabbit/src/rabbit.erl

@@ -176,7 +176,7 @@
                     {enables,     core_initialized}]}).
 
 -rabbit_boot_step({rabbit_queue_member_eval,
-                   [{description, "TODO"},
+                   [{description, "Queue membership evaluation"},
                     {mfa,         {rabbit_sup, start_restartable_child,
                                    [rabbit_queue_member_eval]}},
                     {requires, [database]}]}).

deps/rabbit/src/rabbit_queue_member_eval.erl

@@ -180,23 +180,13 @@ should_add_node(MemberNodes, New, Q, TargetSize) ->
     maybe
         true ?= CurrentSize < TargetSize, %% Target size not reached
         true ?= (TargetSize - CurrentSize) =< length(New), %% Enough nodes,
-        true ?= rabbit_nodes:is_running(lists:delete(node(), MemberNodes)),
-        true ?= are_members_up_to_date(MemberNodes, Q)
+        true ?= rabbit_nodes:is_running(lists:delete(node(), MemberNodes))
     end.
 
-are_members_up_to_date(_MemberNodes, _Q) ->
-    %% _RaMetrics = erpc:multicall(lists:delete(node(), MemberNodes),
-    %%                             ets,
-    %%                             lookup,
-    %%                             [ra_metrics, amqqueue:get_name(Q)], 10000),
-    %% _LocalMetric = ets:lookup(ra_metrics, amqqueue:get_name(Q)),
-    %% Do something with the result
-    true.
-
 get_target_size(Q, undefined) ->
     get_target_size(Q);
-get_target_size(_Q, N) when N > 0 ->
-    N.
+get_target_size(Q, N) when N > 0 ->
+    max(N, get_target_size(Q)).
 
 get_target_size(Q) ->
     case rabbit_policy:get(<<"target-group-size">>, Q) of

deps/rabbit/src/rabbit_quorum_queue.erl

@@ -121,7 +121,11 @@
 
 -rabbit_boot_step(
    {?MODULE,
-    [{description, "QQ policy validation"},
+    [{description, "QQ target group size policies. "
+      "target-group-size controls the targeted number of "
+      "member nodes for the queue. If set, RabbitMQ will try to "
+      "grow the queue members to the target size. "
+      "See module rabbit_queue_member_eval."},
      {mfa, {rabbit_registry, register,
             [policy_validator, <<"target-group-size">>, ?MODULE]}},
      {mfa, {rabbit_registry, register,
@@ -138,8 +142,8 @@ validate_policy(Args) ->
         false -> {error, "~tp is not a valid qq target count value", [Count]}
     end.
 
-merge_policy_value(<<"target-group-size">>, _Val, OpVal) ->
-    OpVal.
+merge_policy_value(<<"target-group-size">>, Val, OpVal) ->
+    max(Val, OpVal).
 
 %%----------- rabbit_queue_type ---------------------------------------------