diff --git a/src/emqttd.app.src b/src/emqttd.app.src
index 4e77ea1bb..9a6abc4ce 100644
--- a/src/emqttd.app.src
+++ b/src/emqttd.app.src
@@ -6,7 +6,9 @@
   {modules, []},
   {registered, []},
   {applications, [kernel,
-                  stdlib]},
+                  stdlib,
+                  gproc,
+                  esockd]},
   {mod, {emqttd_app, []}},
   {env, []}
  ]}.
diff --git a/src/emqttd_pubsub.erl b/src/emqttd_pubsub.erl
index 8ca3b88ab..31823b8da 100644
--- a/src/emqttd_pubsub.erl
+++ b/src/emqttd_pubsub.erl
@@ -186,6 +186,24 @@ init([Pool, Id, _Opts]) ->
     ?GPROC_POOL(join, Pool, Id),
     {ok, #state{pool = Pool, id = Id}}.
 
+prioritise_call(Msg, _From, _Len, _State) ->
+    case Msg of
+        {subscribe, _, _} -> 1;
+        _                 -> 0
+    end.
+
+prioritise_cast(Msg, _Len, _State) ->
+    case Msg of
+        {unsubscribe, _, _} -> 2;
+        _                   -> 0
+    end.
+
+prioritise_info(Msg, _Len, _State) ->
+    case Msg of
+        {'DOWN', _, _, _, _} -> 3;
+        _                    -> 0
+    end.
+
 %%TODO: clientId???
 handle_call({subscribe, _SubPid, TopicTable}, _From, State) ->
     Records = [#mqtt_topic{topic = Topic, node = node()} || {Topic, _Qos} <- TopicTable],