[ https://issues.apache.org/jira/browse/YARN-2009?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15514393#comment-15514393
]
Eric Payne commented on YARN-2009:
----------------------------------
bq. So we could take a max(guaranteed, used). Will this be fine?
I don't think so. If {{tq.getActuallyToBePreempted}} is non-zero, it represents the amount
that will be preempted from what {{tq}} is currently using, not {{tq}}'s guaranteed resources.
The purpose of this line of code is to set {{tq}}'s unallocated resources. But even if {{tq}}
is below it's guarantee, the amount of resources that intra-queue preemption should consider
when balancing is not the queue's guarantee, it's what the queue is already using. If {{tq}}
is below its guarantee, inter-queue preemption should be handling that.
bq. app1 of user1 used entire queue. app2 of user2 asks more resource
The use case I'm referencing regarding this code is not regarding 2 different users. It's
regarding the same user submitting jobs of different priorities. If {{user1}} submits a low
priority job that consumes the whole queue, {{user1}}'s headroom will be 0. Then, when {{user1}}
submits a second app at a higher priority, this code will cause the second app to starve because
{{user1}} has already used up its allocation.
> Priority support for preemption in ProportionalCapacityPreemptionPolicy
> -----------------------------------------------------------------------
>
> Key: YARN-2009
> URL: https://issues.apache.org/jira/browse/YARN-2009
> Project: Hadoop YARN
> Issue Type: Sub-task
> Components: capacityscheduler
> Reporter: Devaraj K
> Assignee: Sunil G
> Attachments: YARN-2009.0001.patch, YARN-2009.0002.patch
>
>
> While preempting containers based on the queue ideal assignment, we may need to consider
preempting the low priority application containers first.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: yarn-issues-unsubscribe@hadoop.apache.org
For additional commands, e-mail: yarn-issues-help@hadoop.apache.org
|