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https://issues.apache.org/jira/browse/MAPREDUCE-4819?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13505806#comment-13505806
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Jason Lowe commented on MAPREDUCE-4819:
---------------------------------------

See JobHistoryEventHandler.closeEventWriter and moveToDoneNow.  That's what's 
moving the job history file from the staging directory to the done intermediate 
directory so the history server picks it up.  We need to not delete the file 
after we move it.
                
> AM can rerun job after reporting final job status to the client
> ---------------------------------------------------------------
>
>                 Key: MAPREDUCE-4819
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-4819
>             Project: Hadoop Map/Reduce
>          Issue Type: Bug
>          Components: mr-am
>    Affects Versions: 0.23.3, 2.0.1-alpha
>            Reporter: Jason Lowe
>            Assignee: Bikas Saha
>            Priority: Critical
>         Attachments: MAPREDUCE-4819.1.patch
>
>
> If the AM reports final job status to the client but then crashes before 
> unregistering with the RM then the RM can run another AM attempt.  Currently 
> AM re-attempts assume that the previous attempts did not reach a final job 
> state, and that causes the job to rerun (from scratch, if the output format 
> doesn't support recovery).
> Re-running the job when we've already told the client the final status of the 
> job is bad for a number of reasons.  If the job failed, it's confusing at 
> best since the client was already told the job failed but the subsequent 
> attempt could succeed.  If the job succeeded there could be data loss, as a 
> subsequent job launched by the client tries to consume the job's output as 
> input just as the re-attempt starts removing output files in preparation for 
> the output commit.

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