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https://issues.apache.org/jira/browse/YARN-6319?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15925161#comment-15925161
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Haibo Chen commented on YARN-6319:
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Thanks [~zhiguohong] for the analysis! This seems an important issue to fix.
Just to make sure we are looking at the same code, was this found in trunk
(3.0-alpha3)? I think solution 1 is the best given that the files that need to
deleted have been deleted anyway, so it is safe to ignore the error. I have
not, however, checked how clean it is to check for file-not-exist error in the
app-cleanup process. Solution 2, or adding post-callback to FileDeletionTask
makes FileDeletionTask more complicated. Solution 3 is even more so.
> race condition between deleting app dir and deleting container dir
> ------------------------------------------------------------------
>
> Key: YARN-6319
> URL: https://issues.apache.org/jira/browse/YARN-6319
> Project: Hadoop YARN
> Issue Type: Bug
> Components: nodemanager
> Reporter: Hong Zhiguo
> Assignee: Hong Zhiguo
>
> Last container (on one node) of one app complete
> | --> triggers async deletion of container dir (container cleanup)
> | --> triggers async deletion of app dir (app cleanup)
> For LCE, deletion is done by container-executor. The "app cleanup" lists
> sub-dir (step 1), and then unlink items one by one(step 2). If a file is
> deleted by "container cleanup" between step 1 and step2, it'll report below
> error and breaks the deletion.
> {code}
> ContainerExecutor: Couldn't delete file
> $LOCAL/usercache/$USER/appcache/application_1481785469354_353539/container_1481785469354_353539_01_000028/$FILE
> - No such file or directory
> {code}
> This app dir then escape the cleanup. And that's why we always have many app
> dirs left there.
> solution 1: just ignore the error without breaking in
> container-executor.c::delete_path()
> solution 2: use a lock to serialize the cleanup of same app dir.
> solution 3: backoff and retry on error
> Comments are welcome.
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