diff --git a/etc/emq.conf b/etc/emq.conf
index acac4e5b5..3bcadfaf8 100644
--- a/etc/emq.conf
+++ b/etc/emq.conf
@@ -783,21 +783,21 @@ listener.tcp.external.send_timeout_close = on
 ## See: listener.tcp.<name>.recbuf
 ##
 ## Value: Bytes
-## listener.tcp.internal.recbuf = 4KB
+## listener.tcp.internal.recbuf = 16KB
 
 ## The TCP send buffer(os kernel) for internal MQTT connections.
 ##
 ## See: http://erlang.org/doc/man/inet.html
 ##
 ## Value: Bytes
-## listener.tcp.internal.sndbuf = 4KB
+## listener.tcp.internal.sndbuf = 16KB
 
 ## The size of the user-level software buffer used by the driver.
 ##
 ## See: listener.tcp.<name>.buffer
 ##
 ## Value: Bytes
-## listener.tcp.internal.buffer = 4KB
+## listener.tcp.internal.buffer = 16KB
 
 ## Sets the 'buffer = max(sndbuf, recbuf)' if this option is enabled.
 ##