[
https://issues.apache.org/jira/browse/MAPREDUCE-7474?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17846064#comment-17846064
]
ASF GitHub Bot commented on MAPREDUCE-7474:
-------------------------------------------
steveloughran opened a new pull request, #6825:
URL: https://github.com/apache/hadoop/pull/6825
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
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
