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Ahmed Hussein commented on MAPREDUCE-7169: ------------------------------------------ Thanks [~BilwaST] ! {quote}With change like this, there are chances that task attempt will get launched on same node where it was launched which wouldn't solve the problem. If we blacklist node then in next iteration of containers assigned it will be launched on other node. {quote} 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. > 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! -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: mapreduce-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: mapreduce-issues-h...@hadoop.apache.org