[
https://issues.apache.org/jira/browse/YARN-5139?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15645782#comment-15645782
]
Carlo Curino commented on YARN-5139:
------------------------------------
[~wangda] first of all, yes it is ok to do this in a later patch, provided the
refactorings here do account for that (i.e., make it easier than it is today).
The point I am making is a bit more structural, I agree that the code you quote
does achieve the same (ignore partially fairness). My point however,
was that if we decide to not do fairness we can short-circuit lots of the
scheduler complexity (the above check doesn't really simplify the scheduler,
just affect some of its decisions). The above is useful functionally, but I
don't think substantially simplifies the scheduler nor affect performance
drastically.
So the point is let's organize the code so that if we decide to run "without
fairness" we can employ a much simplified (and more parallel) scheduler.
Makes sense?
> [Umbrella] Move YARN scheduler towards global scheduler
> -------------------------------------------------------
>
> Key: YARN-5139
> URL: https://issues.apache.org/jira/browse/YARN-5139
> Project: Hadoop YARN
> Issue Type: New Feature
> Reporter: Wangda Tan
> Assignee: Wangda Tan
> Attachments: Explanantions of Global Scheduling (YARN-5139)
> Implementation.pdf, YARN-5139-Concurrent-scheduling-performance-report.pdf,
> YARN-5139-Global-Schedulingd-esign-and-implementation-notes-v2.pdf,
> YARN-5139-Global-Schedulingd-esign-and-implementation-notes.pdf,
> YARN-5139.000.patch, wip-1.YARN-5139.patch, wip-2.YARN-5139.patch,
> wip-3.YARN-5139.patch, wip-4.YARN-5139.patch, wip-5.YARN-5139.patch
>
>
> Existing YARN scheduler is based on node heartbeat. This can lead to
> sub-optimal decisions because scheduler can only look at one node at the time
> when scheduling resources.
> Pseudo code of existing scheduling logic looks like:
> {code}
> for node in allNodes:
> Go to parentQueue
> Go to leafQueue
> for application in leafQueue.applications:
> for resource-request in application.resource-requests
> try to schedule on node
> {code}
> Considering future complex resource placement requirements, such as node
> constraints (give me "a && b || c") or anti-affinity (do not allocate HBase
> regionsevers and Storm workers on the same host), we may need to consider
> moving YARN scheduler towards global scheduling.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
