[ https://issues.apache.org/jira/browse/MAPREDUCE-4815?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14322441#comment-14322441 ]
Gera Shegalov commented on MAPREDUCE-4815: ------------------------------------------ Thanks for v11, Siqi! *FileOutputComitter* Pull the info statement {code} LOG.info("File Output Committer Algorithm version is " + algorithmVersion); {code} out of {{if (outputPath != null) {}} Tests: *TestFileOutputCommitter* (both classes) There are still tests, e.g. {{testAbort}}, {{testFailAbort}} that are [not tested with both committers|https://issues.apache.org/jira/browse/MAPREDUCE-4815?focusedCommentId=14299437&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14299437]. Currently directory contents are only validated for {{version == 1}} in {{testRecovery/CommitInternal}}. You should define and validate content for version 2 as well. > FileOutputCommitter.commitJob can be very slow for jobs with many output files > ------------------------------------------------------------------------------ > > Key: MAPREDUCE-4815 > URL: https://issues.apache.org/jira/browse/MAPREDUCE-4815 > Project: Hadoop Map/Reduce > Issue Type: Bug > Components: mrv2 > Affects Versions: 0.23.3, 2.0.1-alpha, 2.4.1 > Reporter: Jason Lowe > Assignee: Siqi Li > Attachments: MAPREDUCE-4815.v10.patch, MAPREDUCE-4815.v11.patch, > MAPREDUCE-4815.v3.patch, MAPREDUCE-4815.v4.patch, MAPREDUCE-4815.v5.patch, > MAPREDUCE-4815.v6.patch, MAPREDUCE-4815.v7.patch, MAPREDUCE-4815.v8.patch, > MAPREDUCE-4815.v9.patch > > > If a job generates many files to commit then the commitJob method call at the > end of the job can take minutes. This is a performance regression from 1.x, > as 1.x had the tasks commit directly to the final output directory as they > were completing and commitJob had very little to do. The commit work was > processed in parallel and overlapped the processing of outstanding tasks. In > 0.23/2.x, the commit is single-threaded and waits until all tasks have > completed before commencing. -- This message was sent by Atlassian JIRA (v6.3.4#6332)