Immediate updates after memory vm highwatermark change

3 files changed, 18 insertions, 6 deletions

diff --git a/src/rabbit_control.erl b/src/rabbit_control.erl
index 9034c81f99..22e2312ee0 100644
--- a/src/rabbit_control.erl
+++ b/src/rabbit_control.erl
@@ -91,6 +91,9 @@ start() ->
             print_error("invalid command '~s'",
                         [string:join([atom_to_list(Command) | Args], " ")]),
             usage();
+        {badarg, Reason} ->
+            print_error("invalid parameter: ~s ~p", [Reason, Args]),
+            usage();
         {error, Reason} ->
             print_error("~p", [Reason]),
             quit(2);
@@ -322,9 +325,13 @@ action(trace_off, Node, [], Opts, Inform) ->
     rpc_call(Node, rabbit_trace, stop, [list_to_binary(VHost)]);
 
 action(set_vm_memory_high_watermark, Node, [Arg], _Opts, Inform) ->
-    Frac = list_to_float("0" ++ Arg),
-    Inform("Setting memory threshhold on ~p to ~p", [Node, Frac]),
-    rpc_call(Node, vm_memory_monitor, set_vm_memory_high_watermark, [Frac]);
+    try list_to_float(Arg) of
+        Frac -> Inform("Setting memory threshhold on ~p to ~p", [Node, Frac]),
+                rpc_call(Node, vm_memory_monitor, set_vm_memory_high_watermark,
+                         [Frac])
+    catch
+        error:badarg = X -> {X, "invalid floating point format"}
+    end;
 
 action(set_permissions, Node, [Username, CPerm, WPerm, RPerm], Opts, Inform) ->
     VHost = proplists:get_value(?VHOST_OPT, Opts),
diff --git a/src/rabbit_tests.erl b/src/rabbit_tests.erl
index cd5d9be0cc..c8810dfb81 100644
--- a/src/rabbit_tests.erl
+++ b/src/rabbit_tests.erl
@@ -1252,6 +1252,11 @@ test_server_status() ->
     %% list consumers
     ok = control_action(list_consumers, []),
 
+    %% set vm memory high watermark
+    io:format("Expecting failure: "),
+    {badarg, _} = control_action(set_vm_memory_high_watermark, ["1"]),
+    ok = control_action(set_vm_memory_high_watermark, ["1.0"]),
+
     %% cleanup
     [{ok, _} = rabbit_amqqueue:delete(QR, false, false) || QR <- [Q, Q2]],
 
diff --git a/src/vm_memory_monitor.erl b/src/vm_memory_monitor.erl
index 3b95591488..01597a236c 100644
--- a/src/vm_memory_monitor.erl
+++ b/src/vm_memory_monitor.erl
@@ -111,7 +111,7 @@ init([MemFraction]) ->
     State = #state { timeout = ?DEFAULT_MEMORY_CHECK_INTERVAL,
                      timer = TRef,
                      alarmed = false},
-    {ok, internal_update(set_mem_limits(State, MemFraction))}.
+    {ok, set_mem_limits(State, MemFraction)}.
 
 handle_call(get_vm_memory_high_watermark, _From, State) ->
     {reply, State#state.memory_limit / State#state.total_memory, State};
@@ -175,8 +175,8 @@ set_mem_limits(State, MemFraction) ->
     MemLim = get_mem_limit(MemFraction, TotalMemory),
     error_logger:info_msg("Memory limit set to ~pMB of ~pMB total.~n",
                           [trunc(MemLim/?ONE_MB), trunc(TotalMemory/?ONE_MB)]),
-    State #state { total_memory = TotalMemory,
-                   memory_limit = MemLim }.
+    internal_update(State #state { total_memory = TotalMemory,
+                                   memory_limit = MemLim }).
 
 internal_update(State = #state { memory_limit = MemLimit,
                                  alarmed = Alarmed}) ->