diff --git a/rel/files/emqttd.config.development b/rel/files/emqttd.config.development
index 6ec4754c6..16c475523 100644
--- a/rel/files/emqttd.config.development
+++ b/rel/files/emqttd.config.development
@@ -176,36 +176,50 @@
         %% File to store loaded plugin names.
         {loaded_file, "./data/loaded_plugins"}
     ]},
+
     %% Listeners
     {listeners, [
         {mqtt, 1883, [
             %% Size of acceptor pool
             {acceptors, 16},
+
             %% Maximum number of concurrent clients
             {max_clients, 512},
+
             %% Socket Access Control
             {access, [{allow, all}]},
-            %% Rate Limit. Format is 'burst, rate', Unit is KB/Sec
-            %% {rate_limit, "100,10"}, %% 100K burst, 10K rate
+
+            %% Connection Options
+            {connopts, [
+                %% Rate Limit. Format is 'burst, rate', Unit is KB/Sec
+                %% {rate_limit, "100,10"} %% 100K burst, 10K rate
+            ]},
+
             %% Socket Options
             {sockopts, [
                 %Set buffer if hight thoughtput
                 %{recbuf, 4096},
                 %{sndbuf, 4096},
                 %{buffer, 4096},
+                %{nodelay, true},
                 {backlog, 512}
             ]}
         ]},
+
         {mqtts, 8883, [
             %% Size of acceptor pool
             {acceptors, 4},
+
             %% Maximum number of concurrent clients
             {max_clients, 512},
+
             %% Socket Access Control
             {access, [{allow, all}]},
+
             %% SSL certificate and key files
             {ssl, [{certfile, "etc/ssl/ssl.crt"},
                    {keyfile,  "etc/ssl/ssl.key"}]},
+
             %% Socket Options
             {sockopts, [
                 {backlog, 1024}
@@ -229,6 +243,7 @@
         %%      {backlog, 1024}
         %%  ]}
         %%]},
+
         %% HTTP and WebSocket Listener
         {http, 8083, [
             %% Size of acceptor pool
diff --git a/rel/files/emqttd.config.production b/rel/files/emqttd.config.production
index e3685518f..a657d7bf3 100644
--- a/rel/files/emqttd.config.production
+++ b/rel/files/emqttd.config.production
@@ -185,7 +185,8 @@
                 %{recbuf, 4096},
                 %{sndbuf, 4096},
                 %{buffer, 4096},
-                {backlog, 512}
+                %{nodelay, true},
+                {backlog, 1024}
             ]}
         ]},
         {mqtts, 8883, [