memcache 问题 socket or its streams already null in trueClose call

问题现象：

20台服务器有一台报monitor错误 ，查询日志：

05 11 09:37:48 [MaintThread] ERROR memcached.SockIOPool - ++++ failed to close SockIO obj from deadPool
05 11 09:37:48 [MaintThread] ERROR memcached.SockIOPool - ++++ socket or its streams already null in trueClose call
java.io.IOException: ++++ socket or its streams already null in trueClose call
at cn.vika.memcached.SockIOPool$SockIO.trueClose(SockIOPool.java:1929)
at cn.vika.memcached.SockIOPool.selfMaint(SockIOPool.java:1146)
at cn.vika.memcached.SockIOPool$MaintThread.run(SockIOPool.java:1661)

线上后端有类似的错误

05 18 14:39:23 [Thread-1:StreamingReceiver] ERROR c.t.t.s.StreamingReceiver - streaming process error
java.io.IOException: ++++ Stream appears to be dead, so closing it down
at cn.t.trackurl.streaming.SimpleStreamingClient.readLineBytes(SimpleStreamingClient.java:113) ~[trackurl-1.0-SNAPSHOT.jar:na]
at cn.t.trackurl.streaming.StreamingReceiver.run(StreamingReceiver.java:51) ~[trackurl-1.0-SNAPSHOT.jar:na]
at java.lang.Thread.run(Thread.java:662) [na:1.6.0_24]
05 18 14:39:23 [Thread-1:StreamingReceiver] INFO c.t.t.s.SimpleStreamingClient - connect to the streaming server OK