[🐛 Bug]: Distributor OutOfMemery error

[DmiDvor]

What happened?

Hi. There is an OOM (Out of Memory) issue in the Kubernetes cluster for the Selenium Grid.
Selenium Distributor freezes periodically, and sessions start piling up in the queue. Pod resource consumption is normal. However, the logs show OutOfMemory errors.

Command used to start Selenium Grid with Docker (or Kubernetes)

I used this repo to install in k8s cluster https://github.com/SeleniumHQ/docker-selenium (Helm)

Relevant log output

Caused by: java.lang.OutOfMemoryError: unable to create native thread: possibly out of memory or process/resource limits reached
	at java.base/java.lang.Thread.start0(Native Method)
	at java.base/java.lang.Thread.start(Thread.java:1553)
	at java.base/java.lang.System$2.start(System.java:2577)
	at java.base/jdk.internal.vm.SharedThreadContainer.start(SharedThreadContainer.java:152)
	at java.base/java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:953)
	at java.base/java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1375)
	at java.net.http/jdk.internal.net.http.HttpClientImpl$DelegatingExecutor.ensureExecutedAsync(HttpClientImpl.java:183)
	at java.net.http/jdk.internal.net.http.HttpClientImpl$DelegatingExecutor.execute(HttpClientImpl.java:175)
	at java.net.http/jdk.internal.net.http.common.SequentialScheduler.runOrSchedule(SequentialScheduler.java:282)
	at java.net.http/jdk.internal.net.http.common.SequentialScheduler.runOrSchedule(SequentialScheduler.java:251)
	at java.net.http/jdk.internal.net.http.common.SSLFlowDelegate$Reader.incoming(SSLFlowDelegate.java:317)
	at java.net.http/jdk.internal.net.http.common.SubscriberWrapper.incomingCaller(SubscriberWrapper.java:438)
	at java.net.http/jdk.internal.net.http.common.SubscriberWrapper.onNext(SubscriberWrapper.java:379)
	at java.net.http/jdk.internal.net.http.common.SubscriberWrapper.onNext(SubscriberWrapper.java:57)
	at java.net.http/jdk.internal.net.http.SocketTube$InternalReadPublisher$InternalReadSubscription.read(SocketTube.java:865)
	at java.net.http/jdk.internal.net.http.SocketTube$SocketFlowTask.run(SocketTube.java:181)
	at java.net.http/jdk.internal.net.http.common.SequentialScheduler$SchedulableTask.run(SequentialScheduler.java:207)
	at java.net.http/jdk.internal.net.http.common.SequentialScheduler.runOrSchedule(SequentialScheduler.java:280)
	at java.net.http/jdk.internal.net.http.common.SequentialScheduler.runOrSchedule(SequentialScheduler.java:233)
	at java.net.http/jdk.internal.net.http.SocketTube$InternalReadPublisher$InternalReadSubscription.signalReadable(SocketTube.java:782)
	at java.net.http/jdk.internal.net.http.SocketTube$InternalReadPublisher$ReadEvent.signalEvent(SocketTube.java:965)
	at java.net.http/jdk.internal.net.http.SocketTube$SocketFlowEvent.handle(SocketTube.java:253)
	at java.net.http/jdk.internal.net.http.HttpClientImpl$SelectorManager.handleEvent(HttpClientImpl.java:1477)
	at java.net.http/jdk.internal.net.http.HttpClientImpl$SelectorManager.lambda$run$3(HttpClientImpl.java:1422)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)
	at java.net.http/jdk.internal.net.http.HttpClientImpl$SelectorManager.run(HttpClientImpl.java:1422)

Operating System

Ubuntu

Docker Selenium version (image tag)

0.4.39-20251212

Selenium Grid chart version (chart version)

0.50.1

[github-actions]

@DmiDvor, thank you for creating this issue. We will troubleshoot it as soon as we can.

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Thank you!

[VietND96]

@DmiDvor, once the new image tag 4.41.0 is released, please try it and let us know if it can be resolved.

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.