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https://issues.apache.org/jira/browse/YARN-2004?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14326582#comment-14326582
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Wangda Tan commented on YARN-2004:
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[~sunilg],
Thanks for uploading patch,

I just read comments from [~jlowe], I think what he said all make sense to me. 

For scenario#1 
There're some possible solutions to tackle the priority inversion problem you 
just mentioned. But it is more important to make CS with basic priority works 
first. What you said is more like adjustable priority, which could be updated 
according to application's waiting time or other factors.

For scenario#2
It is possible that a user with higher priority application comes but there's 
no available resource in a queue, preemption policy should reclaim resource 
from other users. YARN-2009 should cover it.

General approach of the patch looks good to me.

> Priority scheduling support in Capacity scheduler
> -------------------------------------------------
>
>                 Key: YARN-2004
>                 URL: https://issues.apache.org/jira/browse/YARN-2004
>             Project: Hadoop YARN
>          Issue Type: Sub-task
>          Components: capacityscheduler
>            Reporter: Sunil G
>            Assignee: Sunil G
>         Attachments: 0001-YARN-2004.patch
>
>
> Based on the priority of the application, Capacity Scheduler should be able 
> to give preference to application while doing scheduling.
> Comparator<FiCaSchedulerApp> applicationComparator can be changed as below.   
>         
> 1.    Check for Application priority. If priority is available, then return 
> the highest priority job.
> 2.    Otherwise continue with existing logic such as App ID comparison and 
> then TimeStamp comparison.



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