[DIRMINA-1111] 100% CPU (epoll bug) on 2.1.x, Linux only

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.1.2
• Fix Version/s: 2.1.3
• Assignee: Unassigned
• Reporter: Guus der Kinderen
• Created: 17/May/19 14:21
• Updated: 25/May/19 06:12
• Resolved: 25/May/19 06:12

Description

We're getting reports reports of a bug that causes 100% CPU usage on Linux (the problem does not occur on Windows).

This problem occurs in 2.1.2. but does not occur in 2.0.21.

Is this a regression of the epoll selector bug in DIRMINA-678 ?

A stack trace of one of the spinning threads:

"NioProcessor-3" #55 prio=5 os_prio=0 tid=0x00007f0408002000 nid=0x2a6a runnable [0x00007f0476dee000]
   java.lang.Thread.State: RUNNABLE
	at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
	at sun.nio.ch.EPollArrayWrapper.poll(EPollArrayWrapper.java:269)
	at sun.nio.ch.EPollSelectorImpl.doSelect(EPollSelectorImpl.java:93)
	at sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86)
	- locked <0x00000004c486b748> (a sun.nio.ch.Util$3)
	- locked <0x00000004c486b738> (a java.util.Collections$UnmodifiableSet)
	- locked <0x00000004c420ccb0> (a sun.nio.ch.EPollSelectorImpl)
	at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:97)
	at org.apache.mina.transport.socket.nio.NioProcessor.select(NioProcessor.java:112)
	at org.apache.mina.core.polling.AbstractPollingIoProcessor$Processor.run(AbstractPollingIoProcessor.java:616)
	at org.apache.mina.util.NamePreservingRunnable.run(NamePreservingRunnable.java:64)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)

   Locked ownable synchronizers:
	- <0x00000004c4d03530> (a java.util.concurrent.ThreadPoolExecutor$Worker)

More info is available at https://discourse.igniterealtime.org/t/openfire-4-3-2-cpu-goes-at-100-after-a-few-hours-on-linux/85119/13

Issue Links

• relates to: DIRMINA-678 NioProcessor 100% CPU usage on Linux (epoll selector bug)