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https://issues.apache.org/jira/browse/FLINK-28515?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17569682#comment-17569682
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Roman Khachatryan commented on FLINK-28515:
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I have some concerns regarding the proposed solution: if the
AsyncSnapshotCallable is still running at the time of abort notification then
folder deletion might fail.
Probably a more robust solution would be to delete any local outdated
checkpoints/folders on checkpoint confirmation. So that the deletion will
succeed *eventually*. To list all old checkpoint folders we might either list
folders directly using FS or change the API (instead of only constructing the
path, contruct it, mkdir, and register with TaskLocalStateStore ).
This way missing abort notifications will also be tolerated.
I'm also not sure about the exact reason (and maybe there are multiple).
Is the issue reproducible?
If it could it be transformed into a test that could be a good first step IMO.
WDYT?
> The files in local recovery directory hasn't be clean up properly after
> checkpoint abort
> ----------------------------------------------------------------------------------------
>
> Key: FLINK-28515
> URL: https://issues.apache.org/jira/browse/FLINK-28515
> Project: Flink
> Issue Type: Bug
> Components: Runtime / Checkpointing, Runtime / State Backends
> Affects Versions: 1.15.1, 1.16.0
> Reporter: Jinzhong Li
> Assignee: Jinzhong Li
> Priority: Major
> Labels: pull-request-available
> Attachments: C7245668-CE31-4F56-B9CB-12E2F1E900C5.png,
> image-2022-07-19-18-28-20-239.png, image.png
>
>
> In my case, i found that some files in local recovery directory hasn't be
> clean up properly after checkpoint abort(as shown in the attached picture).
> By analyzing flink log, I found that when stateBackend completes the local
> snapshot but the task has not completed the whole snapshot,
> then checkpoint is aborted (caused by checkpoint timeout or netword-error),
> files in the local directory directory may not be cleaned up properly.
> I think the reason for local snapshot file residual is:
> (1) In the org.apache.flink.streaming.runtime.tasks.AsyncCheckpointRunnable,
> the comleted localSnapshot info can be registered into
> org.apache.flink.runtime.state.TaskLocalStateStoreImpl only after task has
> completed the whole snapshot.
> ([AsyncCheckpointRunnable.java#L136|https://github.com/apache/flink/blob/3ec376601f836df6314e771b243ca6f896a7f642/flink-streaming-java/src/main/java/org/apache/flink/streaming/runtime/tasks/AsyncCheckpointRunnable.java#L136]).
> (2) If stateBackend completes the local snapshot but the task has not
> completed the entire snapshot, when checkpoint-aborting is triggered, the
> TaskLocalStateStore can't clean up the unregistered localSnapshot files.
> ([TaskLocalStateStoreImpl.java#L301|https://github.com/apache/flink/blob/3ec376601f836df6314e771b243ca6f896a7f642/flink-runtime/src/main/java/org/apache/flink/runtime/state/TaskLocalStateStoreImpl.java#L301])
> To fix this problem, I think when TaskLocalStateStoreImpl abort Checkpoint,
> we can try to delete the corresponding localRecovery directory, even if the
> checkpoint is not unregistered into TaskLocalStateStoreImpl.
>
>
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