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https://issues.apache.org/jira/browse/MAPREDUCE-7169?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17095502#comment-17095502
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Bilwa S T commented on MAPREDUCE-7169:
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Hi [~ahussein]
{code:java}
The same node will be picked if there are no other available nodes. In 
MAPREDUCE-7169.005.patch , what is the expected behavior if the resources 
available to run the taskAttempt are only available on the same node? I do not 
see this case in the unit test.{code}

Container is not assigned until resources are available on other node. 

> Speculative attempts should not run on the same node
> ----------------------------------------------------
>
>                 Key: MAPREDUCE-7169
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-7169
>             Project: Hadoop Map/Reduce
>          Issue Type: New Feature
>          Components: yarn
>    Affects Versions: 2.7.2
>            Reporter: Lee chen
>            Assignee: Bilwa S T
>            Priority: Major
>         Attachments: MAPREDUCE-7169-001.patch, MAPREDUCE-7169-002.patch, 
> MAPREDUCE-7169-003.patch, MAPREDUCE-7169.004.patch, MAPREDUCE-7169.005.patch, 
> image-2018-12-03-09-54-07-859.png
>
>
>           I found in all versions of yarn, Speculative Execution may set the 
> speculative task to the node of  original task.What i have read is only it 
> will try to have one more task attempt. haven't seen any place mentioning not 
> on same node.It is unreasonable.If the node have some problems lead to tasks 
> execution will be very slow. and then placement the speculative  task to same 
> node cannot help the  problematic task.
>          In our cluster (version 2.7.2,2700 nodes),this phenomenon appear 
> almost everyday.
>  !image-2018-12-03-09-54-07-859.png! 



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