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https://issues.apache.org/jira/browse/YARN-2964?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14250802#comment-14250802
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Jason Lowe commented on YARN-2964:
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IIUC it worked in the past because typically the Oozie launcher job hangs
around waiting for all the sub-jobs to complete (e.g.: launcher is running a
pig client). Since the launcher job was the first to request the token, it's
the one that remains in the set. Any attempt to add the token by a sub-job
will not actually add it because of the way the hashcode and equals methods on
DelegationTokenToRenew work. Therefore when a sub-job completes and it tries
to remove the tokens, this token will not match because the app ID is for the
launcher and nto the sub-job.
> RM prematurely cancels tokens for jobs that submit jobs (oozie)
> ---------------------------------------------------------------
>
> Key: YARN-2964
> URL: https://issues.apache.org/jira/browse/YARN-2964
> Project: Hadoop YARN
> Issue Type: Bug
> Components: resourcemanager
> Affects Versions: 2.6.0
> Reporter: Daryn Sharp
> Assignee: Jian He
> Priority: Blocker
>
> The RM used to globally track the unique set of tokens for all apps. It
> remembered the first job that was submitted with the token. The first job
> controlled the cancellation of the token. This prevented completion of
> sub-jobs from canceling tokens used by the main job.
> As of YARN-2704, the RM now tracks tokens on a per-app basis. There is no
> notion of the first/main job. This results in sub-jobs canceling tokens and
> failing the main job and other sub-jobs. It also appears to schedule
> multiple redundant renewals.
> The issue is not immediately obvious because the RM will cancel tokens ~10
> min (NM livelyness interval) after log aggregation completes. The result is
> an oozie job, ex. pig, that will launch many sub-jobs over time will fail if
> any sub-jobs are launched >10 min after any sub-job completes. If all other
> sub-jobs complete within that 10 min window, then the issue goes unnoticed.
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