# SEVERE: Couldn't clean up oid=2 from null
**URL:** https://community.jenkins.io/t/severe-couldnt-clean-up-oid-2-from-null/14166
**Category:** Ask a question
**Tags:** question
**Created:** [April 12, 2024, 12:16am UTC](https://community.jenkins.io/t/severe-couldnt-clean-up-oid-2-from-null/14166 "2024-04-12T00:16:19Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@current817](https://community.jenkins.io/u/current817)
#### Post date: [April 12, 2024, 12:16am UTC](https://community.jenkins.io/t/severe-couldnt-clean-up-oid-2-from-null/14166/1 "2024-04-12T00:16:19Z")
Jenkins setup:
## Jenkins: 2.319.2 OS: Linux - 5.4.0-122-generic Java: 11.0.14.1 - Eclipse Adoptium (OpenJDK 64-Bit Server VM)
// Plugins skipped
Hi,
When running a swarm agent on our worker node, we observed the following errors:
```auto
Apr 10, 2024 8:54:51 PM hudson.remoting.jnlp.Main$CuiListener
INFO: Jenkins agent is running in headless mode.
Apr 10, 2024 8:54:51 PM hudson.remoting.jnlp.Main createEngine
WARNING: Certificate validation for HTTPs endpoints is disabled
Apr 10, 2024 8:54:51 PM hudson.remoting.Engine startEngine
INFO: Using Remoting version: 4.5
Apr 10, 2024 8:54:51 PM org.jenkinsci.remoting.engine.WorkDirManager initializeWorkDir
INFO: Using ./remoting as a remoting work directory
Apr 10, 2024 8:54:51 PM org.jenkinsci.remoting.engine.WorkDirManager setupLogging
INFO: Both error and output logs will be printed to ./remoting
Apr 10, 2024 8:54:51 PM hudson.remoting.jnlp.Main$CuiListener status
INFO: Locating server among [https://prod.waterfall.com/jenkins/]
Apr 10, 2024 8:54:51 PM org.jenkinsci.remoting.engine.JnlpAgentEndpointResolver openURLConnection
WARNING: HTTPs certificate check is disabled for the endpoint.
Apr 10, 2024 8:54:51 PM org.jenkinsci.remoting.engine.JnlpAgentEndpointResolver resolve
INFO: Remoting server accepts the following protocols: [JNLP4-connect, Ping]
Apr 10, 2024 8:54:51 PM org.jenkinsci.remoting.engine.JnlpAgentEndpointResolver resolve
INFO: Remoting TCP connection tunneling is enabled. Skipping the TCP Agent Listener Port availability check
Apr 10, 2024 8:54:51 PM hudson.remoting.jnlp.Main$CuiListener status
INFO: Agent discovery successful
Agent address: ptx-aws-waterfall-prod-k8ctl-06
Agent port: xxxxx
Identity: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Apr 10, 2024 8:54:51 PM hudson.remoting.jnlp.Main$CuiListener status
INFO: Handshaking
Apr 10, 2024 8:54:51 PM hudson.remoting.jnlp.Main$CuiListener status
INFO: Connecting to ptx-aws-waterfall-prod-k8ctl-06:32418
Apr 10, 2024 8:54:51 PM hudson.remoting.jnlp.Main$CuiListener status
INFO: Trying protocol: JNLP4-connect
Apr 10, 2024 8:54:51 PM hudson.remoting.jnlp.Main$CuiListener status
INFO: Remote identity confirmed: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Apr 10, 2024 8:54:52 PM hudson.remoting.jnlp.Main$CuiListener status
INFO: Connected
Apr 10, 2024 8:54:54 PM hudson.remoting.RemoteInvocationHandler$Unexporter run
SEVERE: Couldn't clean up oid=2 from null
java.lang.OutOfMemoryError: unable to create new native thread
at java.lang.Thread.start0(Native Method)
at java.lang.Thread.start(Thread.java:717)
at java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:957)
at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1378)
at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134)
at hudson.remoting.DelegatingExecutorService.submit(DelegatingExecutorService.java:48)
at hudson.remoting.InterceptingExecutorService.submit(InterceptingExecutorService.java:46)
at hudson.remoting.InterceptingExecutorService.submit(InterceptingExecutorService.java:41)
at org.jenkinsci.remoting.util.AnonymousClassWarnings.check(AnonymousClassWarnings.java:66)
at org.jenkinsci.remoting.util.AnonymousClassWarnings$1.annotateClass(AnonymousClassWarnings.java:122)
at java.io.ObjectOutputStream.writeNonProxyDesc(ObjectOutputStream.java:1290)
at java.io.ObjectOutputStream.writeClassDesc(ObjectOutputStream.java:1231)
at java.io.ObjectOutputStream.writeNonProxyDesc(ObjectOutputStream.java:1294)
at java.io.ObjectOutputStream.writeClassDesc(ObjectOutputStream.java:1231)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1427)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
at hudson.remoting.Command.writeTo(Command.java:111)
at hudson.remoting.AbstractByteBufferCommandTransport.write(AbstractByteBufferCommandTransport.java:287)
at hudson.remoting.Channel.send(Channel.java:766)
at hudson.remoting.RemoteInvocationHandler$PhantomReferenceImpl.cleanup(RemoteInvocationHandler.java:398)
at hudson.remoting.RemoteInvocationHandler$PhantomReferenceImpl.access$1000(RemoteInvocationHandler.java:357)
at hudson.remoting.RemoteInvocationHandler$Unexporter.run(RemoteInvocationHandler.java:615)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at hudson.remoting.AtmostOneThreadExecutor$Worker.run(AtmostOneThreadExecutor.java:118)
at java.lang.Thread.run(Thread.java:748)
```
It looks like the worker node ran out of native JVM threads, but what does this mean?
```auto
SEVERE: Couldn't clean up oid=2 from null
```
Thanks for any insights!
---
### Author:  [@MarkEWaite](https://community.jenkins.io/u/MarkEWaite)
#### Post date: [April 12, 2024, 12:21pm UTC](https://community.jenkins.io/t/severe-couldnt-clean-up-oid-2-from-null/14166/2 "2024-04-12T12:21:16Z")
> [@current817](#):
>
> Jenkins: 2.319.2
There are comments in [JENKINS-65873](https://issues.jenkins.io/browse/JENKINS-65873) that changes were made in Jenkins remoting for Jenkins 2.361.1 and later that can address the failure to create native threads. [Jenkins 2.319.2](https://www.jenkins.io/changelog-stable/2.319.2/) was released over two years ago. It has known security vulnerabilities. You should upgrade to the most recent Jenkins release so that you get the latest fixes and improvements.
> [@current817](#):
>
> Java: 11.0.14.1
There are comments in [JENKINS-68199](https://issues.jenkins.io/browse/JENKINS-68199) that newer releases of Java 11 are believed to reduce the incidence of the failure to create a native thread. Java 11.0.23 is the current patch level. Java is patched every 3 months with new fixes. Java 11.0.14 is two years old. Upgrade to Java 11.0.23. Even if you can’t upgrade to a newer Jenkins version, I think that you should upgrade your Java version.
---
### Author:  [@current817](https://community.jenkins.io/u/current817)
#### Post date: [April 21, 2024, 11:57pm UTC](https://community.jenkins.io/t/severe-couldnt-clean-up-oid-2-from-null/14166/3 "2024-04-21T23:57:25Z")
@MarkEWaite The 2 threads are very helpful. Thank you very much for such detailed response and for your time. I will look into upgrading our Jenkins controller and the hudson remoting lib.