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https://issues.apache.org/jira/browse/YARN-1434?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13829761#comment-13829761
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Sandy Ryza commented on YARN-1434:
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This seems possible. To further spell this out:
Imagine an AM that, by fairness, receives a container on an NM heartbeat. If
it retrieves the container from the RM and gives it back before any other NM
can heartbeat, it will also, by fairness, receive the next container that the
RM allocates. In this way, it could starve all the other applications on the
cluster. An AM that deserves more than a single container could do this with a
slower heartbeat interval.
For the Fair Scheduler, YARN-1010, which decouples container allocations from
node heartbeats, should solve this in most cases. With it, it is nearly
impossible for an AM to return containers before the RM allocates other free
space to other applications.
> Single Job can affect fairshare of others
> -----------------------------------------
>
> Key: YARN-1434
> URL: https://issues.apache.org/jira/browse/YARN-1434
> Project: Hadoop YARN
> Issue Type: Bug
> Components: resourcemanager
> Reporter: Carlo Curino
> Priority: Minor
>
> A job receiving containers and deciding not to use them and yielding them
> back in the next heartbeat could significantly affect the amount of resources
> given to other jobs.
> This is because by yielding containers back the job appears always to be
> under-capacity (more than others) so it is picked to be the next to receive
> containers.
> Observed by Robert Grandl, to be independently confirmed.
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