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https://issues.apache.org/jira/browse/YARN-8292?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16477674#comment-16477674
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Eric Payne commented on YARN-8292:
----------------------------------

Thanks [~ssath...@hortonworks.com] and [~leftnoteasy].

[~leftnoteasy], Can you please clarify the following:
{noformat}
// - After preempt the container, the to-obtain should be either > 0
// OR any major resource equals to 0.
...
//     * before: <30, 10, 5>, after <20, 10, -10>
{noformat}
In this proposal, should preemption continue after the above? After a container 
is subtracted in the above example, {{resToObtain == <20, 10, -10>}} and the 
next container request is {{<10, 15, 5>}}, would the process continue so we 
would have the following?

{noformat}
// * before: <20, 10, -10>, after: <10, -5, -15>
{noformat}

 

> Fix the dominant resource preemption cannot happen when some of the resource 
> vector becomes negative
> ----------------------------------------------------------------------------------------------------
>
>                 Key: YARN-8292
>                 URL: https://issues.apache.org/jira/browse/YARN-8292
>             Project: Hadoop YARN
>          Issue Type: Bug
>          Components: yarn
>            Reporter: Sumana Sathish
>            Assignee: Wangda Tan
>            Priority: Critical
>             Fix For: 3.2.0, 3.1.1
>
>         Attachments: YARN-8292.001.patch
>
>
>  
>  This is an example of the problem: (Same if we have more than 2 resources)
>   
> Let's say we have 3 queues A/B/C. All containers with equal size <2,3>
>  
> ||Queue||Guaranteed||Used ||Pending||
> |A|<20, 10>|<20,30>| |
> |B|<20, 10>|0|0|
> |C|<20, 10>|0|<20, 30>|
> | | | | |
>  
> Under current logic, A's calculated to-preempt (how much resource other queue 
> can preempt) will be <0, 20>. The preemption will not happen. However, under 
> the context of DRC, queue A is using more resource than guaranteed, so queue 
> C will be starved



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