fix mem leak (#30) (#31)

Author: ariesdevil

README.md

@@ -1,4 +1,4 @@
-# GoBeansDB [![Build Status](https://travis-ci.org/douban/gobeansdb.svg?branch=master)](https://travis-ci.org/douban/gobeansdb) 
+# GoBeansDB [![Build Status](https://travis-ci.org/douban/gobeansdb.svg?branch=master)](https://travis-ci.org/douban/gobeansdb) [![Release](https://img.shields.io/github/v/release/douban/gobeansdb)](https://github.com/douban/gobeansdb/releases)
 
 Yet anonther distributed key-value storage system from Douban Inc.
 

memcache/server.go

@@ -158,6 +158,7 @@ func (c *ServerConn) ServeOnce(storageClient StorageClient, stats *Stats) (err e
 	if !resp.Noreply {
 		if !readTimeout && overdue(req.ReceiveTime, time.Now()) {
 			req.SetStat("process_timeout")
+			resp.CleanBuffer()
 			resp = new(Response)
 			resp.Status = "PROCESS_TIMEOUT"
 			resp.Msg = "process_timeout"