[
https://issues.apache.org/jira/browse/HADOOP-4018?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
dhruba borthakur updated HADOOP-4018:
-------------------------------------
Attachment: maxSplits9.patch
Incorporated all review comments except one.
If the limit check fails, the JT raises an exception after marking the job as
failed. Amar had commented that it is not required to mark the job status as
"failed" before raising the exception. But I have seen that unless this status
is set, a job that is expected to fail does not fail. the unit test will then
fail.
> limit memory usage in jobtracker
> --------------------------------
>
> Key: HADOOP-4018
> URL: https://issues.apache.org/jira/browse/HADOOP-4018
> Project: Hadoop Core
> Issue Type: Bug
> Components: mapred
> Reporter: dhruba borthakur
> Assignee: dhruba borthakur
> Attachments: maxSplits.patch, maxSplits2.patch, maxSplits3.patch,
> maxSplits4.patch, maxSplits5.patch, maxSplits6.patch, maxSplits7.patch,
> maxSplits8.patch, maxSplits9.patch
>
>
> We have seen instances when a user submitted a job with many thousands of
> mappers. The JobTracker was running with 3GB heap, but it was still not
> enough to prevent memory trashing from Garbage collection; effectively the
> Job Tracker was not able to serve jobs and had to be restarted.
> One simple proposal would be to limit the maximum number of tasks per job.
> This can be a configurable parameter. Is there other things that eat huge
> globs of memory in job Tracker?
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
