[Done][DUBBO] dubbo Thread pool is EXHAUSTED!

 異常信息：

com.alibaba.dubbo.remoting.ExecutionException: class com.alibaba.dubbo.remoting.transport.dispatcher.all.AllChannelHandler error when process caught event .
        at com.alibaba.dubbo.remoting.transport.dispatcher.all.AllChannelHandler.caught(AllChannelHandler.java:67)
        at com.alibaba.dubbo.remoting.transport.AbstractChannelHandlerDelegate.caught(AbstractChannelHandlerDelegate.java:44)
        at com.alibaba.dubbo.remoting.transport.AbstractChannelHandlerDelegate.caught(AbstractChannelHandlerDelegate.java:44)
        at com.alibaba.dubbo.remoting.transport.AbstractPeer.caught(AbstractPeer.java:127)
        at com.alibaba.dubbo.remoting.transport.netty.NettyHandler.exceptionCaught(NettyHandler.java:112)
        at com.alibaba.dubbo.remoting.transport.netty.NettyCodecAdapter$InternalDecoder.exceptionCaught(NettyCodecAdapter.java:165)
        at org.jboss.netty.channel.Channels.fireExceptionCaught(Channels.java:525)
        at org.jboss.netty.channel.AbstractChannelSink.exceptionCaught(AbstractChannelSink.java:48)
        at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:296)
        at com.alibaba.dubbo.remoting.transport.netty.NettyCodecAdapter$InternalDecoder.messageReceived(NettyCodecAdapter.java:148)
        at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:268)
        at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:255)
        at org.jboss.netty.channel.socket.nio.NioWorker.read(NioWorker.java:88)
        at org.jboss.netty.channel.socket.nio.AbstractNioWorker.process(AbstractNioWorker.java:109)
        at org.jboss.netty.channel.socket.nio.AbstractNioSelector.run(AbstractNioSelector.java:312)
        at org.jboss.netty.channel.socket.nio.AbstractNioWorker.run(AbstractNioWorker.java:90)
        at org.jboss.netty.channel.socket.nio.NioWorker.run(NioWorker.java:178)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
        at java.lang.Thread.run(Thread.java:745)
Caused by: java.util.concurrent.RejectedExecutionException: Thread pool is EXHAUSTED! Thread Name: DubboServerHandler-192.168.120.213:20880, 
Pool Size: 200 (active: 200, core: 200, max: 200, largest: 200), Task: 3839523 (completed: 3839323), 
Executor status:(isShutdown:false, isTerminated:false, isTerminating:false), in dubbo://192.168.120.213:20880!
        at com.alibaba.dubbo.common.threadpool.support.AbortPolicyWithReport.rejectedExecution(AbortPolicyWithReport.java:53)
        at java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:823)
        at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1369)
        at com.alibaba.dubbo.remoting.transport.dispatcher.all.AllChannelHandler.caught(AllChannelHandler.java:65)
        ... 19 common frames omitted

提示線程池滿了，若有新請求進入的時候，會拒絕執行。

 

來一張官方的圖：

 

上圖Dispatcher后面跟着的ThreadPool就是我們所說的業務線程池。Dispatcher分為5類，默認是all，解釋也直接參考官方截圖：

 而dubbo默認為all模式，查看源碼（可見all模式下相關事件都使用了業務線程池）：

all模式下線程池：

 

 

修改dubbo配置文件：

    <dubbo:protocol name="dubbo" port="${dubbo.port}" accesslog="false" threads="500" dispatcher="message"/>

 

修改后，啟用MessageOnlyChannelHandler，源碼如下（此時只有receive業務方法獨享線程池）：

 

參考： http://manzhizhen.iteye.com/blog/2391177

 

以上。