diff --git a/apps/emqtt/src/emqtt_broker.erl b/apps/emqtt/src/emqtt_broker.erl
index 479c6f0ec..5905a6337 100644
--- a/apps/emqtt/src/emqtt_broker.erl
+++ b/apps/emqtt/src/emqtt_broker.erl
@@ -79,6 +79,7 @@ datetime() ->
 %% gen_server Function Definitions
 %% ------------------------------------------------------------------
 init([Options]) ->
+    random:seed(now()),
     SysInterval = proplists:get_value(sys_interval, Options, 60),
     % Create $SYS Topics
     [{atomic, _} = create(systop(Name)) || Name <- ?SYSTOP_BROKERS],
@@ -88,8 +89,8 @@ init([Options]) ->
     [ets:insert(?TABLE, {Name, 0}) || Name <- ?SYSTOP_CLIENTS],
     [ets:insert(?TABLE, {Name, 0}) || Name <- ?SYSTOP_PUBSUB],
     % retain version, description
-    gen_server:cast(self(), prepare),
-    {ok, tick(#state{started_at = os:timestamp(), sys_interval = SysInterval})}.
+    State = #state{started_at = os:timestamp(), sys_interval = SysInterval},
+    {ok, tick(random:uniform(SysInterval), State)}.
 
 handle_call(uptime, _From, State) ->
     {reply, uptime(State), State};
@@ -97,15 +98,12 @@ handle_call(uptime, _From, State) ->
 handle_call(_Request, _From, State) ->
     {reply, ok, State}.
 
-handle_cast(prepare, State) ->
-    retain(systop(version), list_to_binary(version())),
-    retain(systop(description), list_to_binary(description())),
-    {noreply, State};
-
 handle_cast(_Msg, State) ->
     {noreply, State}.
 
 handle_info(tick, State) ->
+    retain(systop(version), list_to_binary(version())),
+    retain(systop(description), list_to_binary(description())),
     publish(systop(uptime), list_to_binary(uptime(State))),
     publish(systop(datetime), list_to_binary(datetime())),
     %%TODO... call emqtt_cm here?
@@ -161,7 +159,10 @@ uptime(days, D) ->
     [integer_to_list(D), " days,"].
 
 tick(State = #state{sys_interval = SysInterval}) ->
-    State#state{tick_timer = erlang:send_after(SysInterval * 1000, self(), tick)}.
+    tick(SysInterval, State).
+
+tick(Delay, State) ->
+    State#state{tick_timer = erlang:send_after(Delay * 1000, self(), tick)}.
 
 i2b(I) when is_integer(I) ->
     list_to_binary(integer_to_list(I)).
diff --git a/apps/emqtt/src/emqtt_metrics.erl b/apps/emqtt/src/emqtt_metrics.erl
index 99ab28d12..5efa99dd1 100644
--- a/apps/emqtt/src/emqtt_metrics.erl
+++ b/apps/emqtt/src/emqtt_metrics.erl
@@ -142,6 +142,7 @@ key(Metric) ->
 %% gen_server Function Definitions
 %% ------------------------------------------------------------------
 init(Options) ->
+    random:seed(now()),
     Topics = ?SYSTOP_BYTES ++ ?SYSTOP_PACKETS ++ ?SYSTOP_MESSAGES,
     % $SYS Topics for metrics
     [{atomic, _} = emqtt_pubsub:create(systop(Topic)) || Topic <- Topics],
@@ -150,10 +151,7 @@ init(Options) ->
     % Init metrics
     [new_metric(Topic) || Topic <- Topics],
     PubInterval = proplists:get_value(pub_interval, Options, 60),
-    {ok, tick(#state{pub_interval = PubInterval}), hibernate}.
-
-handle_call(get_metrics, _From, State) ->
-    {reply, [], State};
+    {ok, tick(random:uniform(PubInterval), #state{pub_interval = PubInterval}), hibernate}.
 
 handle_call(_Request, _From, State) ->
     {reply, ok, State}.
@@ -190,7 +188,10 @@ new_metric(Name) ->
     [ets:insert(?TABLE, {{Name, I}, 0}) || I <- Schedulers].
 
 tick(State = #state{pub_interval = PubInterval}) ->
-    State#state{tick_timer = erlang:send_after(PubInterval * 1000, self(), tick)}.
+    tick(PubInterval, State).
+
+tick(Delay, State) ->
+    State#state{tick_timer = erlang:send_after(Delay * 1000, self(), tick)}.
 
 i2b(I) ->
     list_to_binary(integer_to_list(I)).