[
https://issues.apache.org/jira/browse/MAPREDUCE-7017?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16281660#comment-16281660
]
jiayuhan-it edited comment on MAPREDUCE-7017 at 12/7/17 10:42 AM:
------------------------------------------------------------------
cc [~asuresh] and @Konstantinos Karanasos
Please help to review.
was (Author: magicbunny):
cc @Arun Suresh and @Konstantinos Karanasos
Please help to review.
> Too many times of meaningless invocation in TaskAttemptImpl#resolveHosts
> ------------------------------------------------------------------------
>
> Key: MAPREDUCE-7017
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-7017
> Project: Hadoop Map/Reduce
> Issue Type: Improvement
> Components: mr-am
> Affects Versions: 3.0.0-alpha4
> Reporter: jiayuhan-it
> Attachments: MAPREDUCE-7017.001.patch
>
>
> MRAppMaster uses {{TaskAttemptImpl::resolveHosts}} to determine the
> dataLocalHosts for each task when the location of data split is IP, which
> will call a lot of times ( taskNum * dfsReplication) of function
> {{InetAddress::getByName}} and most of the funcition calls are redundant.
> When the job has a great number of tasks and the speed of DNS resolution is
> not fast enough, it will take a lot of time at this stage before the job
> running.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
