重启服务后，dubbo线程池DubboServerHandler频繁创建线程，直至资源耗尽

[0x9bb1]

• [√] I have searched the issues of this repository and believe that this is not a duplicate.
• [√] I have checked the FAQ of this repository and believe that this is not a duplicate.

Environment

• Dubbo version: 2.6.1
• Operating System version: centOS7
• Java version: 1.7

Steps to reproduce this issue

1. 停机服务，重启
2. dubbo无法注册到zk，已检查端口和ip无异常
3. DubboServerHandler一直启线程，直到OOM

Expected Result

期望服务重启后，可以正常注册到zk，平稳提供服务

Actual Result

OOM，服务崩溃

If there is an exception, please attach the exception trace:

Exception in thread "DubboServerHandler-10.20.200.108:21030-thread-52" java.lang.OutOfMemoryError: GC overhead limit exceeded
        at java.util.concurrent.ConcurrentHashMap$Segment.put(ConcurrentHashMap.java:457)
        at java.util.concurrent.ConcurrentHashMap.put(ConcurrentHashMap.java:1130)
        at com.alibaba.dubbo.remoting.transport.netty.NettyChannel.setAttribute(NettyChannel.java:153)
        at com.alibaba.dubbo.remoting.exchange.support.header.HeaderExchangeHandler.disconnected(HeaderExchangeHandler.java:118)
        at com.alibaba.dubbo.remoting.transport.AbstractChannelHandlerDelegate.disconnected(AbstractChannelHandlerDelegate.java:45)
        at com.alibaba.dubbo.remoting.transport.dispatcher.ChannelEventRunnable.run(ChannelEventRunnable.java:64)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:745)

[lollapalooza1989]

dubbo无法注册到zk，已检查端口和ip无异常
无法注册到zk时候的具体报错是什么

[0x9bb1]

原因是别的代码侵吞了资源，频繁full GC导致的。

[ly853602]

@zhangnix2 请问下，我也遇到了同样的问题，但是还是不明白dubbo线程池频繁创建线程的原因，可以帮忙解答下吗