You are viewing a plain text version of this content. The canonical link for it is here.
Posted to mapreduce-issues@hadoop.apache.org by "Ahmed Hussein (Jira)" <ji...@apache.org> on 2019/12/30 16:59:00 UTC
[jira] [Comment Edited] (MAPREDUCE-7169) Speculative attempts
should not run on the same node
[ https://issues.apache.org/jira/browse/MAPREDUCE-7169?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17005468#comment-17005468 ]
Ahmed Hussein edited comment on MAPREDUCE-7169 at 12/30/19 4:58 PM:
--------------------------------------------------------------------
[~BilwaST], the patch is not applicable anymore with the trunk. Can you please fix the compilation errors along with the java doc and checkstyle issues?
I see that you add the node hosting the original task to the blacklist of the speculative task. Wouldn't it be easier just to change the order of the dataLocalHosts so that the node will be picked last in the loop? In that case, the speculative task will run on the same node only if all other nodes cannot be assigned to the speculative task.
was (Author: ahussein):
[~BilwaST], the patch is not applicable anymore with the trunk. Can you please fix the compilation errors along with the java doc and checkstyle issues?
I see that you add the node hosting the original task to the blacklist of the speculative task. Wouldn't it be easier just to change the order of the dataLocalHosts so that the node will be picked last in the loop? In that case, the speculative task will run on the same node only if all other nodes cannot be assigned to the speculative task.
> 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, 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!
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: mapreduce-issues-unsubscribe@hadoop.apache.org
For additional commands, e-mail: mapreduce-issues-help@hadoop.apache.org