KAFKA-18337: KafkaProducer Memory Leak in JmxReporter Class

[tmw090906]

Add a close status in JmxReporter, that avoid re-registering metrics to jmx after being closed, which could lead to memory leaks

relate KAFKA-18337

Committer Checklist (excluded from commit message)

• Verify design and implementation
• Verify test coverage and CI build status
• Verify documentation (including upgrade notes)

[github-actions]

A label of 'needs-attention' was automatically added to this PR in order to raise the
attention of the committers. Once this issue has been triaged, the triage label
should be removed to prevent this automation from happening again.

[AndrewJSchofield]

Thanks for the PR. It seems to me that the new defensive code is right down inside the reregister method, but I would have thought that the check on closed could be in the public methods such as init, metricChange and metricRemoval. All of the MBeans were unregistered when the reporter was closed already. wdyt?

[tmw090906]

Thanks for your reply! It seems that all the public methods will eventually call the reregister and the unregister . I think that the unregister method poses no potential risks after the JmxReporter is closed, so I put the check in the reregister method. wdyt?

[AndrewJSchofield]

Thanks for your reply! It seems that all the public methods will eventually call the reregister and the unregister . I think that the unregister method poses no potential risks after the JmxReporter is closed, so I put the check in the reregister method. wdyt?

I prefer to do the closed check on every method which synchronizes on the lock. For one thing, some methods such as metricRemoval mess with the MBean, and then called reregister which fails. This doesn't seem like a very good pattern to me.

[github-actions]

This PR is being marked as stale since it has not had any activity in 90 days. If you
would like to keep this PR alive, please leave a comment asking for a review. If the PR has
merge conflicts, update it with the latest from the base branch.

If you are having difficulty finding a reviewer, please reach out on the [mailing list](https://kafka.apache.org/contact).

If this PR is no longer valid or desired, please feel free to close it. If no activity occurs in the next 30 days, it will be automatically closed.

[github-actions]

This PR has been closed since it has not had any activity in 120 days. If you feel like this
was a mistake, or you would like to continue working on it, please feel free to re-open the
PR and ask for a review.