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https://issues.apache.org/jira/browse/MAPREDUCE-7474?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17846062#comment-17846062
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ASF GitHub Bot commented on MAPREDUCE-7474:
-------------------------------------------

steveloughran opened a new pull request, #6824:
URL: https://github.com/apache/hadoop/pull/6824

   
   backport of #6716
   
   Improve task commit resilience everywhere
   and add an option to reduce delete IO requests on
   job cleanup (relevant for ABFS and HDFS).
   
   Task Commit Resilience
   ----------------------
   
   Task manifest saving is re-attempted on failure; the number of  attempts 
made is configurable with the option:
   
     mapreduce.manifest.committer.manifest.save.attempts
   
   * The default is 5.
   * The minimum is 1; asking for less is ignored.
   * A retry policy adds 500ms of sleep per attempt.
   * Move from classic rename() to commitFile() to rename the file, after 
calling getFileStatus() to get its length and possibly etag. This becomes a 
rename() on gcs/hdfs anyway, but on abfs it does reach the 
ResilientCommitByRename callbacks in abfs, which report on the outcome to the 
caller...which is then logged at WARN.
   * New statistic task_stage_save_summary_file to distinguish from other 
saving operations (job success/report file). This is only saved to the manifest 
on task commit retries, and provides statistics on all previous unsuccessful 
attempts to save the manifests
   + test changes to match the codepath changes, including improvements in 
fault injection.
   
   Directory size for deletion
   ---------------------------
   
   New option
   
     mapreduce.manifest.committer.cleanup.parallel.delete.base.first
   
   This attempts an initial attempt at deleting the base dir, only falling back 
to parallel deletes if there's a timeout.
   
   This option is disabled by default; Consider enabling it for abfs to reduce 
IO load. Consult the documentation for more details.
   
   Success file printing
   ---------------------
   
   The command to print a JSON _SUCCESS file from this committer and any S3A 
committer is now something which can be invoked from the mapred command:
   
     mapred successfile <path to file>
   
   Contributed by Steve Loughran
   
   
   ### How was this patch tested?
   
   yetus's work, if happy will validate on abfs.
   
   ### For code changes:
   
   - [ ] Does the title or this PR starts with the corresponding JIRA issue id 
(e.g. 'HADOOP-17799. Your PR title ...')?
   - [ ] Object storage: have the integration tests been executed and the 
endpoint declared according to the connector-specific documentation?
   - [ ] If adding new dependencies to the code, are these dependencies 
licensed in a way that is compatible for inclusion under [ASF 
2.0](http://www.apache.org/legal/resolved.html#category-a)?
   - [ ] If applicable, have you updated the `LICENSE`, `LICENSE-binary`, 
`NOTICE-binary` files?
   
   




> [ABFS] Improve commit resilience and performance in Manifest Committer
> ----------------------------------------------------------------------
>
>                 Key: MAPREDUCE-7474
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-7474
>             Project: Hadoop Map/Reduce
>          Issue Type: Bug
>          Components: client
>    Affects Versions: 3.4.0, 3.3.6
>            Reporter: Steve Loughran
>            Assignee: Steve Loughran
>            Priority: Major
>              Labels: pull-request-available
>
> * Manifest committer is not resilient to rename failures on task commit 
> without HADOOP-18012 rename recovery enabled. 
> * large burst of delete calls noted: are they needed?
> relates to HADOOP-19093 but takes a more minimal approach with goal of 
> changes in manifest committer only.
> Initial proposed changes
> * retry recovery on task commit rename, always (repeat save, delete, rename)
> * audit delete use and see if it can be pruned



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