ManagedSelector#processUpdates#ConcurrentModificationException

[huyunduoduo]

Jetty version(s)
9.4.52

Jetty Environment

Java version/vendor
1.8.0_201

OS type/version
Linux

Description
An error log is generated when the service is running for a period of time
WARNING:

java.util.ConcurrentModificationException
	at java.util.ArrayDeque$DeqIterator.next(ArrayDeque.java:648)
	at org.eclipse.jetty.io.ManagedSelector$SelectorProducer.processUpdates(ManagedSelector.java:560)
	at org.eclipse.jetty.io.ManagedSelector$SelectorProducer.produce(ManagedSelector.java:539)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.produceTask(EatWhatYouKill.java:362)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:186)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:173)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:131)
	at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:409)
	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:883)
	at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:1034)
	at java.lang.Thread.run(Thread.java:748)

At this point, the process still exists, but cannot provide services

Restart the service and restore to normal. About 2 hours later, the exception and symptom occur again

[joakime]

This community support issue on Jetty 9 will not be answered.
Jetty 9 is at End of Community Support.

• EoCS (End of Community Support) for Jetty 9 - June 2022 #7958
• EoCS (End of Community Support) for Jetty 10 / Jetty 11 - January 2024 #10485

If this happens on a supported version of Jetty (currently Jetty 12) we can help you.
If you need to continue to use javax.servlet, the ee8 environment on Jetty 12 still supports that old namespace.