When clicking on build, it looks like nothing is happening: the build is not appearing in the Jenkins Queue.
- CloudBees CI (CloudBees Core).
- CloudBees CI (CloudBees Core) on modern cloud platforms - Managed Master
- CloudBees CI (CloudBees Core) on modern cloud platforms - Operations Center
- CloudBees CI (CloudBees Core) on traditional platforms - Client Master
- CloudBees CI (CloudBees Core) on traditional platforms - Operations Center
- CloudBees Jenkins Enterprise
- CloudBees Jenkins Enterprise - Managed Master
- CloudBees Jenkins Enterprise - Operations Center
- CloudBees Jenkins Team
- CloudBees Jenkins Platform - Client Master
- CloudBees Jenkins Platform - Operations Center
- Jenkins LTS
This kind of symptoms mean that something is holding a lock on the Jenkins Queue.
For instance, the Docker Plugin prior to 1.0.0 can be affected by this kind of issue.
You can verify that you are experiencing a Deadlock by going into
You should see several threads mentioning
In case you encounter a case like that, it is best to open a case with CloudBees Support.
In case you would like to investigate the issue yourself, you should look into the thread dump for a stack having a lock on the Jenkins Queue and performing long operation.
For instance the following dump exhibits the issue:
at java.net.SocketInputStream.socketRead0(Native Method) <--- socket operation // suppressed for clarity at com.nirima.jenkins.plugins.docker.strategy.DockerOnceRetentionStrategy$1$1.run(DockerOnceRetentionStrategy.java:112) at hudson.model.Queue._withLock(Queue.java:1320) at hudson.model.Queue.withLock(Queue.java:1197) <--- Lock on the Queue at com.nirima.jenkins.plugins.docker.strategy.DockerOnceRetentionStrategy$1.run(DockerOnceRetentionStrategy.java:106) <--- docker plugin // suppressed for clarity
NB: you should take several thread dumps to ensure there is a lock, one single thread dump showing the previous stack is perfectly normal.