[ https://issues.apache.org/jira/browse/YARN-2009?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15520009#comment-15520009
]
Eric Payne commented on YARN-2009:
----------------------------------
Hi [~sunilg]. After thinking more about it, I think I would like to express my ideas about
{{tq.unassigned}} in the following algorithm:
{code}
tq.unassigned = tq.used
while tq.unassigned
for app : underservedApps
app.idealAssigned = app.used + app.pending // considering, of course, user-resource-limit,
as Wangda defined it above
tq.unassigned -= app.idealAssigned
{code}
My concern is that if 1) {{tq.guaranteed}} is used in the above algorithm instead of {{tq.used}},
and 2) if {{tq.used}} is less than {{tq.guaranteed}}, then the above algorithm will want to
ideally assign more total resources to all apps than are being used. If that happens, then
when it comes time for the intra-queue preemption policy to preempt resources, it seems to
me that the policy won't preempt enough resources.
It seems tome that the intra-queue preemption policy should only be considering actually being
used resources when deciding how much to preempt, not guaranteed resources.
> 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
|