[
https://issues.apache.org/jira/browse/YARN-4945?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15468165#comment-15468165
]
Eric Payne commented on YARN-4945:
----------------------------------
Thanks [~sunilg].
{quote}
bq. if it's already in selectedCandidates, it's because an inter-queue
preemption policy put it there
I think I must give some more clarity for what I am trying to do here. Its
possible that there can be some containers which were selected by
priority/user-limit policy may already be selected from inter-queue policies.
In that case, we need not have to mark them again. Rather we can deduct the
resource directly as its container marked for preemption.
{quote}
OK. I think I see what you are saying.
In {{IntraQueueCandidatesSelector#preemptFromLeastStarvedApp}}:
{code}
if (CapacitySchedulerPreemptionUtils.isContainerAlreadySelected(c,
selectedCandidates)) {
Resources.subtractFrom(toObtainByPartition, c.getAllocatedResource());
continue;
}
{code}
IIUC, you are saying that at this point, {{toObtainByPartition}} contains
requested resources from _both_ inter-queue _and_ intra-queue preemption
policies. So, since this container has already been selected by the inter-queue
policies, skip it, stop tracking its resources in {{toObtainByPartition}} (by
subtracting out the container's size), and keep looking for another container
to mark as preemptable. Is that correct?
-----
Also, I think that priority and user-limit-percent preemption policies should
be separate policies. Do you agree? If so, can we please rename
{{IntraQueueCandidatesSelector}} to something like
{{IntraQueuePriorityCandidatesSelector}}
> [Umbrella] Capacity Scheduler Preemption Within a queue
> -------------------------------------------------------
>
> Key: YARN-4945
> URL: https://issues.apache.org/jira/browse/YARN-4945
> Project: Hadoop YARN
> Issue Type: Bug
> Reporter: Wangda Tan
> Attachments: Intra-Queue Preemption Use Cases.pdf,
> IntraQueuepreemption-CapacityScheduler (Design).pdf, YARN-2009-wip.2.patch,
> YARN-2009-wip.patch, YARN-2009-wip.v3.patch
>
>
> This is umbrella ticket to track efforts of preemption within a queue to
> support features like:
> YARN-2009. YARN-2113. YARN-4781.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: yarn-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: yarn-issues-h...@hadoop.apache.org
