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https://issues.apache.org/jira/browse/MAPREDUCE-6478?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Junping Du updated MAPREDUCE-6478:
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    Description: 
In some of our test cases for MR on public cloud scenario, a very big MR job 
with hundreds or thousands of reducers cannot finish successfully because of 
Job Cleanup failures which is caused by different scale/performance impact for 
File System on the cloud (like AzureFS) which replacing HDFS's deletion for 
whole directory with REST API calls on deleting each sub-directories 
recursively. Even it get successfully, that could take much longer time (hours) 
which is not necessary and waste time/resources especially in public cloud 
scenario. 
In these scenarios, some failures of cleanupJob can be ignored or user choose 
to skip cleanupJob() completely make more sense. This is because making whole 
job finish successfully with side effect of wasting some user spaces is much 
better as user's jobs are usually comes and goes in public cloud, so have 
choices to tolerant some temporary files exists with get rid of big job re-run 
(or saving job's running time) is quite effective in time/resource cost. 
We should allow user to have this option (ignore failure or skip job cleanup 
stage completely) especially when user know the cleanup failure is not due to 
HDFS abnormal status but other FS' different performance trade-off.

  was:
In some our test cases for MR on public cloud scenario, a very big MR job with 
hundreds or thousands of reducers cannot finish successfully because of Job 
Cleanup failures which is caused by different scale/performance impact for File 
System on the cloud (like AzureFS) which replacing HDFS's deletion for whole 
directory with REST API calls on deleting each sub-directories recursively. 
That could take much longer time (hours) which is not necessary in public cloud 
scenario. 
Also, it also more easily to get failed to cleanup in these cases, so some 
failures of cleanupJob can be ignored in this case. Making whole job finish 
successfully with side effect of wasting some user spaces make more sense in 
these cases as user's job is usually comes and goes in public cloud, so have a 
trade off to tolerant some temporary files exists with get rid of big job 
re-run is quite cost effective. 
We should allow user to have this option (ignore failure or skip job cleanup 
stage completely) especially when user know the cleanup failure is not due to 
HDFS abnormal status but other FS' different performance trade-off.


> Add an option to skip cleanupJob stage or ignore cleanup failure during 
> commitJob().
> ------------------------------------------------------------------------------------
>
>                 Key: MAPREDUCE-6478
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-6478
>             Project: Hadoop Map/Reduce
>          Issue Type: Improvement
>            Reporter: Junping Du
>            Assignee: Junping Du
>
> In some of our test cases for MR on public cloud scenario, a very big MR job 
> with hundreds or thousands of reducers cannot finish successfully because of 
> Job Cleanup failures which is caused by different scale/performance impact 
> for File System on the cloud (like AzureFS) which replacing HDFS's deletion 
> for whole directory with REST API calls on deleting each sub-directories 
> recursively. Even it get successfully, that could take much longer time 
> (hours) which is not necessary and waste time/resources especially in public 
> cloud scenario. 
> In these scenarios, some failures of cleanupJob can be ignored or user choose 
> to skip cleanupJob() completely make more sense. This is because making whole 
> job finish successfully with side effect of wasting some user spaces is much 
> better as user's jobs are usually comes and goes in public cloud, so have 
> choices to tolerant some temporary files exists with get rid of big job 
> re-run (or saving job's running time) is quite effective in time/resource 
> cost. 
> We should allow user to have this option (ignore failure or skip job cleanup 
> stage completely) especially when user know the cleanup failure is not due to 
> HDFS abnormal status but other FS' different performance trade-off.



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