diff --git a/src/emqttd_client.erl b/src/emqttd_client.erl
index f8794cd92..88f14c2d6 100644
--- a/src/emqttd_client.erl
+++ b/src/emqttd_client.erl
@@ -127,7 +127,7 @@ do_init(Conn, Env, Peername) ->
                                      force_gc_count = ForceGcCount}),
     IdleTimout = get_value(client_idle_timeout, Env, 30000),
     gen_server2:enter_loop(?MODULE, [], State, self(), IdleTimout,
-                           {backoff, 1000, 1000, 10000}).
+                           {backoff, 2000, 2000, 20000}).
 
 send_fun(Conn, Peername) ->
     Self = self(),
@@ -377,6 +377,7 @@ shutdown(Reason, State) ->
 stop(Reason, State) ->
     {stop, Reason, State}.
 
-gc(State) ->
-    emqttd_gc:maybe_force_gc(#client_state.force_gc_count, State).
+gc(State = #client_state{connection = Conn}) ->
+    Cb = fun() -> Conn:gc() end,
+    emqttd_gc:maybe_force_gc(#client_state.force_gc_count, State, Cb).
 
diff --git a/src/emqttd_gc.erl b/src/emqttd_gc.erl
index 04cdbf2d5..75545a77f 100644
--- a/src/emqttd_gc.erl
+++ b/src/emqttd_gc.erl
@@ -20,7 +20,8 @@
 
 -author("Feng Lee <feng@emqtt.io>").
 
--export([conn_max_gc_count/0, reset_conn_gc_count/2, maybe_force_gc/2]).
+-export([conn_max_gc_count/0, reset_conn_gc_count/2, maybe_force_gc/2,
+         maybe_force_gc/3]).
 
 -spec(conn_max_gc_count() -> integer()).
 conn_max_gc_count() ->
@@ -38,9 +39,11 @@ reset_conn_gc_count(Pos, State) ->
     end.
 
 maybe_force_gc(Pos, State) ->
+    maybe_force_gc(Pos, State, fun() -> ok end).
+maybe_force_gc(Pos, State, Cb) ->
     case element(Pos, State) of
         undefined     -> State;
-        I when I =< 0 -> garbage_collect(),
+        I when I =< 0 -> Cb(), garbage_collect(),
                          reset_conn_gc_count(Pos, State);
         I             -> setelement(Pos, State, I - 1)
     end.
diff --git a/src/emqttd_ws_client.erl b/src/emqttd_ws_client.erl
index 4fb57b6ad..4beb7bc40 100644
--- a/src/emqttd_ws_client.erl
+++ b/src/emqttd_ws_client.erl
@@ -104,7 +104,7 @@ init([Env, WsPid, Req, ReplyChannel]) ->
                          proto_state    = ProtoState,
                          enable_stats   = EnableStats,
                          force_gc_count = ForceGcCount},
-     IdleTimeout, {backoff, 1000, 1000, 10000}, ?MODULE}.
+     IdleTimeout, {backoff, 2000, 2000, 20000}, ?MODULE}.
 
 prioritise_call(Msg, _From, _Len, _State) ->
     case Msg of info -> 10; stats -> 10; state -> 10; _ -> 5 end.