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https://issues.apache.org/jira/browse/DIRMINA-678?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12973974#action_12973974
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Victor N commented on DIRMINA-678:
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I have found a bug in our system, it was endless loop in our code and NOT in
mina!
We are using JDK 1.6.0_23 now (but it has some strange changes - it is
difficult to monitor via jstack or jvisualvm, so maybe we will go back to
1.6.0_22 or 21),
I will look how it is working now and whether the bug is reproduced. We use
both Acceptors and Connectors and have tens of thousands IoSessions per server.
If the problem is fixed in JDK itself (which build?), we do not need any
patches of course! Is there any proof/link of this fix in JDK?
> NioProcessor 100% CPU usage on Linux (epoll selector bug)
> ---------------------------------------------------------
>
> Key: DIRMINA-678
> URL: https://issues.apache.org/jira/browse/DIRMINA-678
> Project: MINA
> Issue Type: Bug
> Components: Core
> Affects Versions: 2.0.0-M4
> Environment: CentOS 5.x, 32/64-bit, 32/64-bit Sun JDK 1.6.0_12, also
> _11/_10/_09 and Sun JDK 1.7.0 b50, Kernel 2.6.18-92.1.22.el5 and also older
> versions,
> Reporter: Serge Baranov
> Fix For: 2.0.3
>
> Attachments: snap973.png, snap974.png
>
>
> It's the same bug as described at http://jira.codehaus.org/browse/JETTY-937 ,
> but affecting MINA in the very similar way.
> NioProcessor threads start to eat 100% resources per CPU. After 10-30 minutes
> of running depending on the load (sometimes after several hours) one of the
> NioProcessor starts to consume all the available CPU resources probably
> spinning in the epoll select loop. Later, more threads can be affected by the
> same issue, thus 100% loading all the available CPU cores.
> Sample trace:
> NioProcessor-10 [RUNNABLE] CPU time: 5:15
> sun.nio.ch.EPollArrayWrapper.epollWait(long, int, long, int)
> sun.nio.ch.EPollArrayWrapper.poll(long)
> sun.nio.ch.EPollSelectorImpl.doSelect(long)
> sun.nio.ch.SelectorImpl.lockAndDoSelect(long)
> sun.nio.ch.SelectorImpl.select(long)
> org.apache.mina.transport.socket.nio.NioProcessor.select(long)
> org.apache.mina.core.polling.AbstractPollingIoProcessor$Processor.run()
> org.apache.mina.util.NamePreservingRunnable.run()
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor$Worker)
> java.util.concurrent.ThreadPoolExecutor$Worker.run()
> java.lang.Thread.run()
> It seems to affect any NIO based Java server applications running in the
> specified environment.
> Some projects provide workarounds for similar JDK bugs, probably MINA can
> also think about a workaround.
> As far as I know, there are at least 3 users who experience this issue with
> Jetty and all of them are running CentOS (some distribution default setting
> is a trigger?). As for MINA, I'm not aware of similar reports yet.
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