[
https://issues.apache.org/jira/browse/MAPREDUCE-3902?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14232635#comment-14232635
]
Rohith commented on MAPREDUCE-3902:
-----------------------------------
I wonder this jira has become stale for long time and would like to know the
reason. I personally think this feature would be helpfull in terms of latency
container allocation latency.We have done few analysis and implemented support
for JVM reuse on branch-2 without breaking existing AM functionality. We would
be ready to share prototype patch along with design doc.
> MR AM should reuse containers for map tasks, there-by allowing fine-grained
> control on num-maps for users without need for CombineFileInputFormat etc.
> ------------------------------------------------------------------------------------------------------------------------------------------------------
>
> Key: MAPREDUCE-3902
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-3902
> Project: Hadoop Map/Reduce
> Issue Type: Improvement
> Components: applicationmaster, mrv2
> Reporter: Arun C Murthy
> Assignee: Siddharth Seth
> Attachments: AMContainerRefactorNotes.pdf, AM_ContainerRefactor.pdf,
> MAPREDUCE-3902.2.patch, MAPREDUCE-3902.patch
>
>
> The MR AM is now in a great position to reuse containers across (map) tasks.
> This is something similar to JVM re-use we had in 0.20.x, but in a
> significantly better manner:
> # Consider data-locality when re-using containers
> # Consider the new shuffle - ensure that reduces fetch output of the whole
> container at once (i.e. all maps) : MAPREDUCE-4525
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)