[
https://issues.apache.org/jira/browse/YARN-1769?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13933943#comment-13933943
]
Hadoop QA commented on YARN-1769:
---------------------------------
{color:red}-1 overall{color}. Here are the results of testing the latest
attachment
http://issues.apache.org/jira/secure/attachment/12634513/YARN-1769.patch
against trunk revision .
{color:green}+1 @author{color}. The patch does not contain any @author
tags.
{color:green}+1 tests included{color}. The patch appears to include 5 new
or modified test files.
{color:red}-1 javac{color:red}. The patch appears to cause the build to
fail.
Console output: https://builds.apache.org/job/PreCommit-YARN-Build/3350//console
This message is automatically generated.
> CapacityScheduler: Improve reservations
> ----------------------------------------
>
> Key: YARN-1769
> URL: https://issues.apache.org/jira/browse/YARN-1769
> Project: Hadoop YARN
> Issue Type: Improvement
> Components: capacityscheduler
> Affects Versions: 2.3.0
> Reporter: Thomas Graves
> Assignee: Thomas Graves
> Attachments: YARN-1769.patch, YARN-1769.patch, YARN-1769.patch,
> YARN-1769.patch
>
>
> Currently the CapacityScheduler uses reservations in order to handle requests
> for large containers and the fact there might not currently be enough space
> available on a single host.
> The current algorithm for reservations is to reserve as many containers as
> currently required and then it will start to reserve more above that after a
> certain number of re-reservations (currently biased against larger
> containers). Anytime it hits the limit of number reserved it stops looking
> at any other nodes. This results in potentially missing nodes that have
> enough space to fullfill the request.
> The other place for improvement is currently reservations count against your
> queue capacity. If you have reservations you could hit the various limits
> which would then stop you from looking further at that node.
> The above 2 cases can cause an application requesting a larger container to
> take a long time to gets it resources.
> We could improve upon both of those by simply continuing to look at incoming
> nodes to see if we could potentially swap out a reservation for an actual
> allocation.
--
This message was sent by Atlassian JIRA
(v6.2#6252)