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https://issues.apache.org/jira/browse/MAPREDUCE-6251?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Craig Welch updated MAPREDUCE-6251:
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Attachment: MAPREDUCE-6251.0.patch
Attached is a patch which locates the retry where it is effective in capturing
the state and which provides a configurable retry count/interval which will
address this issue for most reasonable "eventual consistency" timeframes.
Without chaning the overall handoff mechanism to not be based on DFS this is
the best type of fix I believe we can achieve. Moving to synchronous calls to
report history to the JH is another option I think we should consider, but that
is a more significant change I think we will want to consider down the road -
in the meantime this should work around the issue for most cases.
> JobClient needs additional retries at a higher level to address
> not-immediately-consistent dfs corner cases
> -----------------------------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-6251
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-6251
> Project: Hadoop Map/Reduce
> Issue Type: Bug
> Components: jobhistoryserver, mrv2
> Affects Versions: 2.2.0
> Reporter: Craig Welch
> Assignee: Craig Welch
> Attachments: MAPREDUCE-6251.0.patch
>
>
> The JobClient is used to get job status information for running and completed
> jobs. Final state and history for a job is communicated from the application
> master to the job history server via a distributed file system - where the
> history is uploaded by the application master to the dfs and then
> scanned/loaded by the jobhistory server. While HDFS has strong consistency
> guarantees not all Hadoop DFS's do. When used in conjunction with a
> distributed file system which does not have this guarantee there will be
> cases where the history server may not see an uploaded file, resulting in the
> dreaded "no such job" and a null value for the RunningJob in the client.
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