[JENKINS-75007] Jenkins Log Warning (new selector)

[jenkins-infra-bot]

Hi everyone,

 

Since yesteday, jenkins are spamming my var log with this:

 

déc. 17 09:49:01 jameswebb jenkins[880401]: 2024-12-17 08:49:01.364+0000 [id=3048]        WARNING        o.a.m.c.p.AbstractPollingIoProcessor$Processor#run: Create a new selector. Selected is 0, delta = 0

Any idea ?

 

Thanks all

---

Originally reported by sushihash, imported from: Jenkins Log Warning (new selector)

• assignee: fcojfernandez
• status: Open
• priority: Minor
• component(s): ansicolor-plugin, ant-plugin, mina-sshd-api-plugin
• label(s): jenkins
• resolution: Unresolved
• votes: 1
• watchers: 4
• imported: 20251216-182730

Raw content of original issue

Hi everyone,

 

Since yesteday, jenkins are spamming my var log with this:

 

déc. 17 09:49:01 jameswebb jenkins[880401]: 2024-12-17 08:49:01.364+0000 [id=3048]        WARNING        o.a.m.c.p.AbstractPollingIoProcessor$Processor#run: Create a new selector. Selected is 0, delta = 0

Any idea ? 

 

Thanks all

environment

Jenkins version :  2.479.2<br/>
OS : debian bookworm<br/>
plugins : <br/>
ace-editor<br/>
ansible<br/>
ansicolor<br/>
ant<br/>
antisamy-markup-formatter<br/>
ant.jpi.disabled<br/>
build-timeout<br/>
cloudbees-folder<br/>
command-launcher<br/>
credentials<br/>
credentials-binding<br/>
dark-theme<br/>
database<br/>
email-ext<br/>
git<br/>
git-client<br/>
gradle<br/>
gradle.jpi.disabled<br/>
groovy<br/>
handlebars<br/>
instance-identity<br/>
javadoc<br/>
jdk-tool<br/>
jsch<br/>
junit<br/>
mailer<br/>
matrix-auth<br/>
matrix-project<br/>
mattermost<br/>
mattermost.jpi.disabled<br/>
maven-plugin<br/>
maven-plugin.jpi.disabled<br/>
mercurial<br/>
mercurial.jpi.disabled<br/>
metrics<br/>
mina-sshd-api-common<br/>
mina-sshd-api-core<br/>
momentjs<br/>
pam-auth<br/>
pipeline-graph-analysis<br/>
pipeline-graph-view<br/>
pipeline-model-definition<br/>
pipeline-model-extensions<br/>
pipeline-stage-view<br/>
plain-credentials<br/>
redmine<br/>
resource-disposer<br/>
script-security<br/>
solarized-theme<br/>
ssh-credentials<br/>
sshd<br/>
ssh-slaves<br/>
structs<br/>
subversion<br/>
swarm<br/>
theme-manager<br/>
timestamper<br/>
token-macro<br/>
variant<br/>
windows-slaves<br/>
workflow-aggregator<br/>
workflow-basic-steps<br/>
workflow-cps<br/>
workflow-multibranch<br/>
workflow-support

[jenkins-infra-bot]

kon:

• Original comment link
• Raw content of original comment:

  "o.a.m.c.p.AbstractPollingIoProcessor" is likely to mean org.apache.mina.core.polling.AbstractPollingIoProcessor, which might be related to the mina-sshd-api plugin.
  

"o.a.m.c.p.AbstractPollingIoProcessor" is likely to mean org.apache.mina.core.polling.AbstractPollingIoProcessor, which might be related to the mina-sshd-api plugin.

[jenkins-infra-bot]

kon:

• Original comment link
• Raw content of original comment:

  This code would log a warning similar to what you are getting: https://github.com/apache/mina/blob/2.2.3/mina-core/src/main/java/org/apache/mina/core/polling/AbstractPollingIoProcessor.java#L640
  

This code would log a warning similar to what you are getting: https://github.com/apache/mina/blob/2.2.3/mina-core/src/main/java/org/apache/mina/core/polling/AbstractPollingIoProcessor.java#L640

[jenkins-infra-bot]

kon:

• Original comment link
• Raw content of original comment:

  Version 2.1010.v64ec48721231 of SSH Build Agents was released just yesterday.  Did you install that version?  Perhaps it is what causes the new warning.  I didn't find anything related in the Java code changes though.
  

Version 2.1010.v64ec48721231 of SSH Build Agents was released just yesterday. Did you install that version? Perhaps it is what causes the new warning. I didn't find anything related in the Java code changes though.

[jenkins-infra-bot]

sushihash:

• Original comment link
• Raw content of original comment:

  hey, thanks for your time.
  
   
  
  I will investigate on all youre advice
  
   
  
  have a nice day
  
   
  

hey, thanks for your time.

 

I will investigate on all youre advice

 

have a nice day

 

[jenkins-infra-bot]

hjhafner:

• Original comment link
• Raw content of original comment:

  We  updated our Jenkins core from version 2.414.3 to 2.440.3, and also several other plugins.
  Specifically, the 'Mina SSHD API :: Common' and 'Mina SSHD API :: Core' plugins were updated from 2.12.1-101.v85b_e08b_780dd to 2.14.0-143.v2b_362fc39576.
  The version of "SSH Build Agents" plugin is 2.948.vb_8050d697fec.
  
  Upon restarting Jenkins, the log file began to be flooded with the following warning:
   WARNING: org.apache.mina.core.polling.AbstractPollingIoProcessor$Processor run - Create a new selector. Selected is 0, delta = 0 
  
  This resulted in an excessive log file growth rate of approximately 9GB per hour.
  
  Reverting both 'Mina SSHD API :: Common' and 'Mina SSHD API :: Core' plugins back to the previous version 2.12.1-101.v85b_e08b_780dd resolved this issue.
  
  Are there compatibility issues between Jenkins 2.440.3 and the updated Mina SSHD plugins 2.14.0-143.v2b_362fc39576, considering potential interactions with other updated plugins?
  

We  updated our Jenkins core from version 2.414.3 to 2.440.3, and also several other plugins.
Specifically, the 'Mina SSHD API :: Common' and 'Mina SSHD API :: Core' plugins were updated from 2.12.1-101.v85b_e08b_780dd to 2.14.0-143.v2b_362fc39576.
The version of "SSH Build Agents" plugin is 2.948.vb_8050d697fec.

Upon restarting Jenkins, the log file began to be flooded with the following warning:
 WARNING: org.apache.mina.core.polling.AbstractPollingIoProcessor$Processor run - Create a new selector. Selected is 0, delta = 0 

This resulted in an excessive log file growth rate of approximately 9GB per hour.

Reverting both 'Mina SSHD API :: Common' and 'Mina SSHD API :: Core' plugins back to the previous version 2.12.1-101.v85b_e08b_780dd resolved this issue.

Are there compatibility issues between Jenkins 2.440.3 and the updated Mina SSHD plugins 2.14.0-143.v2b_362fc39576, considering potential interactions with other updated plugins?

[jenkins-infra-bot]

hjhafner:

• Original comment link
• Raw content of original comment:

  We  updated our Jenkins core from version 2.440.3 to 2.462.3
  The 'Mina SSHD API :: Common' and 'Mina SSHD API :: Core' plugins were updated from 2.12.1-101.v85b_e08b_780dd to 2.14.0-143.v2b_362fc39576.
  Other related updated plugins:
  SSH Build Agents 2.948.vb_8050d697fec -> 2.973.v0fa_8c0dea_f9f
  Git 5.2.1 -> 5.2.2
  Git client 4.7.0 -> 5.0.3
  
  Again,  the log file began to be flooded with the following warning:
   WARNING: org.apache.mina.core.polling.AbstractPollingIoProcessor$Processor run - Create a new selector. Selected is 0, delta = 0 
  
  Reverting the plugins "Mina SSHD API :: Common", "Mina SSHD API :: Core", "Git", "Git client" and "SSH Build Agents" resolved the issue.
  
  Does anyone know which plugins, in combination with the Mina SSHD plugins, could be responsible for this warning, and which versions work without warnings?
  

We  updated our Jenkins core from version 2.440.3 to 2.462.3
The 'Mina SSHD API :: Common' and 'Mina SSHD API :: Core' plugins were updated from 2.12.1-101.v85b_e08b_780dd to 2.14.0-143.v2b_362fc39576.
Other related updated plugins:
SSH Build Agents 2.948.vb_8050d697fec -> 2.973.v0fa_8c0dea_f9f
Git 5.2.1 -> 5.2.2
Git client 4.7.0 -> 5.0.3

Again,  the log file began to be flooded with the following warning:
 WARNING: org.apache.mina.core.polling.AbstractPollingIoProcessor$Processor run - Create a new selector. Selected is 0, delta = 0 

Reverting the plugins "Mina SSHD API :: Common", "Mina SSHD API :: Core", "Git", "Git client" and "SSH Build Agents" resolved the issue.

Does anyone know which plugins, in combination with the Mina SSHD plugins, could be responsible for this warning, and which versions work without warnings?

[jenkins-infra-bot]

hjhafner:

• Original comment link
• Raw content of original comment:

  Unfortunately, I have not yet figured out how to reproduce this error on our QA Jenkins. The error is only visible on our production system.
  

Unfortunately, I have not yet figured out how to reproduce this error on our QA Jenkins. The error is only visible on our production system.

[jenkins-infra-bot]

markewaite:

• Original comment link
• Raw content of original comment:

  Does anyone know which plugins, in combination with the Mina SSHD plugins, could be responsible for this warning, and which versions work without warnings?
  
  That message is included in a test log of the CLITest.strictHostKey test of the SSH server plugin.  Maybe the installation that is showing the issue is using ssh to access the Jenkins API (through an ssh authenticated call to the Jenkins CLI?)?
  
  I don't see the text 'Create a new selector' in the Apache Mina SSHD source code or in any Jenkins source code.
  
  I don't see that log entry in my Jenkins installation that is testing the 2.528.1 release that will be delivered today.  I don't see that log entry in the 2.516.3 system log on ci.jenkins.io .  Since Jenkins 2.462.3 has several known security vulnerabilities, you should plan to upgrade to a newer version.
  
  This seems like a topic that is best discussed in the Jenkins community forum rather than using a Jenkins issue.  We use Jira for bugs and enhancements.  Question and answer is done at https://community.jenkins.io 
  

Does anyone know which plugins, in combination with the Mina SSHD plugins, could be responsible for this warning, and which versions work without warnings?

That message is included in a test log of the CLITest.strictHostKey test of the SSH server plugin. Maybe the installation that is showing the issue is using ssh to access the Jenkins API (through an ssh authenticated call to the Jenkins CLI?)?

I don't see the text 'Create a new selector' in the Apache Mina SSHD source code or in any Jenkins source code.

I don't see that log entry in my Jenkins installation that is testing the 2.528.1 release that will be delivered today. I don't see that log entry in the 2.516.3 system log on ci.jenkins.io . Since Jenkins 2.462.3 has several known security vulnerabilities, you should plan to upgrade to a newer version.

This seems like a topic that is best discussed in the Jenkins community forum rather than using a Jenkins issue. We use Jira for bugs and enhancements. Question and answer is done at https://community.jenkins.io

[jenkins-infra-bot]

hjhafner:

• Original comment link
• Raw content of original comment:

  Thank you, Mark, for your answer.
  
  To me, this already looks suspiciously like a bug. When I update the two Mina plugins, I start receiving warnings, and if I revert them, the warnings disappear. If these were just a few warnings, we could ignore them. However, our Jenkins ran for a mere 50 minutes and, in that time, wrote 13,189,776 such warnings to the logfile. That's almost 2GB.
  
   
  That message is included in a test log of the CLITest.strictHostKey test of the SSH server plugin. Maybe the installation that is showing the issue is using ssh to access the Jenkins API (through an ssh authenticated call to the Jenkins CLI?)?
  The warning is included 28 times in the test log. I don't see a clear connection to CLI in this context. Nevertheless, I attempted to reproduce the error using CLI commands invoked via SSH on our QA Jenkins environment, but unfortunately, I was unsuccessful.
  
   
  you should plan to upgrade to a newer version
  Yes, I agree. I'm currently in the process of gradually upgrading our Jenkins instance. However, I've unfortunately reached a roadblock. The 'Jenkins LTS Upgrade Guide' for version 2.479.1 explicitly states:
  'You must ensure that all plugins have been updated both before and after upgrading,'
  and regrettably, the Mina plugins are preventing me from fulfilling this requirement.
  
   
  I don't see the text 'Create a new selector' in the Apache Mina SSHD source code or in any Jenkins source code.
  kon wrote above:
  This code would log a warning similar to what you are getting: https://github.com/apache/mina/blob/2.2.3/mina-core/src/main/java/org/apache/mina/core/polling/AbstractPollingIoProcessor.java#L640
   
  
  Our Jenkins installation might also be a contributing factor. It's quite extensive, comprising approximately 1,000 nodes, over 2,600 executors, and nearly 18,000 jobs
  

Thank you, Mark, for your answer.

To me, this already looks suspiciously like a bug. When I update the two Mina plugins, I start receiving warnings, and if I revert them, the warnings disappear. If these were just a few warnings, we could ignore them. However, our Jenkins ran for a mere 50 minutes and, in that time, wrote 13,189,776 such warnings to the logfile. That's almost 2GB.

 

That message is included in a test log of the CLITest.strictHostKey test of the SSH server plugin. Maybe the installation that is showing the issue is using ssh to access the Jenkins API (through an ssh authenticated call to the Jenkins CLI?)?

The warning is included 28 times in the test log. I don't see a clear connection to CLI in this context. Nevertheless, I attempted to reproduce the error using CLI commands invoked via SSH on our QA Jenkins environment, but unfortunately, I was unsuccessful.

 

you should plan to upgrade to a newer version

Yes, I agree. I'm currently in the process of gradually upgrading our Jenkins instance. However, I've unfortunately reached a roadblock. The 'Jenkins LTS Upgrade Guide' for version 2.479.1 explicitly states:

'You must ensure that all plugins have been updated both before and after upgrading,'

and regrettably, the Mina plugins are preventing me from fulfilling this requirement.

 

I don't see the text 'Create a new selector' in the Apache Mina SSHD source code or in any Jenkins source code.

kon wrote above:

This code would log a warning similar to what you are getting: https://github.com/apache/mina/blob/2.2.3/mina-core/src/main/java/org/apache/mina/core/polling/AbstractPollingIoProcessor.java#L640

 

Our Jenkins installation might also be a contributing factor. It's quite extensive, comprising approximately 1,000 nodes, over 2,600 executors, and nearly 18,000 jobs

[jenkins-infra-bot]

markewaite:

• Original comment link
• Raw content of original comment:

  However, our Jenkins ran for a mere 50 minutes and, in that time, wrote 13,189,776 such warnings to the logfile. That's almost 2GB.
  
  I don't see those log entries.  I think that suggests there is something in your environment that is different than my environment.  You could build a private copy of the Mina SSHD plugin and report a stack trace when that message is written.  That would allow you to identify the cause of the message.  I don't see the message in any of the configurations that I checked.
  

However, our Jenkins ran for a mere 50 minutes and, in that time, wrote 13,189,776 such warnings to the logfile. That's almost 2GB.

I don't see those log entries. I think that suggests there is something in your environment that is different than my environment. You could build a private copy of the Mina SSHD plugin and report a stack trace when that message is written. That would allow you to identify the cause of the message. I don't see the message in any of the configurations that I checked.