Observing High CPU in EPollArrayWrapper.epollCtl default I/O thread ------------------------------------------------------------------- Key: WFLY-13444 URL: https://issues.redhat.com/browse/WFLY-13444 Project: WildFly Issue Type: Bug Components: Remoting Affects Versions: 10.1.0.Final Reporter: Srinivas ev Assignee: Flavia Rainone Priority: Major Attachments: IO thread memory.PNG, IO thread.PNG, Thread consuming high CPU.PNG, ThreadDump1set.zip, ThreadDump2set.zip, default IO thread 73.PNG, default io consuming snapshot.PNG, default io consuming.PNG, stack trace from snapshot.PNG, stack trace in thread dump.PNG, threaddump-1589514505334.tdump, top command output.PNG Facing high CPU by one of the default I/O thread In Wildfly 10.1.0 Final. Looks none of our application component thread is consuming. Can somebody check what is triggering this issue? I attached the thread stack to this Jira. This is blocking our releases. When the CPU cores are high in number, multiple default I/O threads will kick in consuming the CPU in 90~100% range continuously. Wildfly 10.1.0 Final Java - openjdk version "1.8.0_232" OpenJDK Runtime Environment (build 1.8.0_232-b09) OpenJDK 64-Bit Server VM (build 25.232-b09, mixed mode --------------------------------------------------------------------------------------------------- at java.lang.Throwable.fillInStackTrace(Native Method) at java.lang.Throwable.fillInStackTrace(Throwable.java:784) at java.lang.Throwable.<init>(Throwable.java:251) at java.lang.Exception.<init>(Exception.java:54) at java.io.IOException.<init>(IOException.java:47) at java.nio.channels.ClosedChannelException.<init>(ClosedChannelException.java:52) at org.xnio.ssl.JsseStreamConduit.write(JsseStreamConduit.java:1022) at org.xnio.conduits.ConduitStreamSinkChannel.write(ConduitStreamSinkChannel.java:150) at org.xnio.http.HttpUpgrade$HttpUpgradeState$StringWriteListener.handleEvent(HttpUpgrade.java:385) at org.xnio.http.HttpUpgrade$HttpUpgradeState$StringWriteListener.handleEvent(HttpUpgrade.java:372) at org.xnio.ChannelListeners.invokeChannelListener(ChannelListeners.java:92) at org.xnio.conduits.WriteReadyHandler$ChannelListenerHandler.writeReady(WriteReadyHandler.java:65) at org.xnio.ssl.JsseStreamConduit.run(JsseStreamConduit.java:393) at org.xnio.ssl.JsseStreamConduit.readReady(JsseStreamConduit.java:547) at org.xnio.ssl.JsseStreamConduit$2.readReady(JsseStreamConduit.java:319) at org.xnio.nio.NioSocketConduit.handleReady(NioSocketConduit.java:89) at org.xnio.nio.WorkerThread.run(WorkerThread.java:567) ------------------------------------------------------------------------------------------- at sun.nio.ch.EPollArrayWrapper.epollCtl(Native Method) at sun.nio.ch.EPollArrayWrapper.updateRegistrations(EPollArrayWrapper.java:299) at sun.nio.ch.EPollArrayWrapper.poll(EPollArrayWrapper.java:268) at sun.nio.ch.EPollSelectorImpl.doSelect(EPollSelectorImpl.java:93) at sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86) at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:97) at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:101) at org.xnio.nio.WorkerThread.run(WorkerThread.java:515) -----------------------------------------------------------------------------------