[ 
https://issues.apache.org/jira/browse/YARN-6681?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16044065#comment-16044065
 ] 

Ying Zhang commented on YARN-6681:
----------------------------------

Hi [~daryn], thanks for asking. I think your changes are fine. And considering 
it will always return "false" for LeafQueue, we should just return false for 
leaf queue.
{quote}
My hesitation was the null check on childQueues, implying an iteration would 
NPE, but it's marked final so always returning true seems safe?
{quote}
I'm thinking the null check is for the case when it is a leaf queue. It should 
always be non-null for a parent queue.

> Eliminate double-copy of child queues in canAssignToThisQueue
> -------------------------------------------------------------
>
>                 Key: YARN-6681
>                 URL: https://issues.apache.org/jira/browse/YARN-6681
>             Project: Hadoop YARN
>          Issue Type: Sub-task
>          Components: resourcemanager
>    Affects Versions: 2.8.0
>            Reporter: Daryn Sharp
>            Assignee: Daryn Sharp
>         Attachments: YARN-6681.2.branch-2.8.patch, 
> YARN-6681.2.branch-2.patch, YARN-6681.2.trunk.patch, 
> YARN-6681.branch-2.8.patch, YARN-6681.branch-2.patch, YARN-6681.trunk.patch
>
>
> 20% of the time in {{AbstractCSQueue#canAssignToThisQueue}} is spent 
> performing two duplications a treemap of child queues into a list - once to 
> test for null, second to see if it's empty.  Eliminating the dups reduces the 
> overhead to 2%.



--
This message was sent by Atlassian JIRA
(v6.3.15#6346)

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to