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https://issues.apache.org/jira/browse/MAPREDUCE-1305?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12832575#action_12832575
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Peter Romianowski commented on MAPREDUCE-1305:
----------------------------------------------

Thanks Chris for remove calls to FsShell. I've been very busy lately so I did 
not manage to compile the patch.

> Running distcp with -delete incurs avoidable penalties
> ------------------------------------------------------
>
>                 Key: MAPREDUCE-1305
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-1305
>             Project: Hadoop Map/Reduce
>          Issue Type: Improvement
>          Components: distcp
>    Affects Versions: 0.20.1
>            Reporter: Peter Romianowski
>            Assignee: Peter Romianowski
>         Attachments: M1305-1.patch, M1305-2.patch, MAPREDUCE-1305.patch
>
>
> *First problem*
> In org.apache.hadoop.tools.DistCp#deleteNonexisting we serialize FileStatus 
> objects when the path is all we need.
> The performance problem comes from 
> org.apache.hadoop.fs.RawLocalFileSystem.RawLocalFileStatus#write which tries 
> to retrieve file permissions by issuing a "ls -ld <path>" which is painfully 
> slow.
> Changed that to just serialize Path and not FileStatus.
> *Second problem*
> To delete the files we invoke the "hadoop" command line tool with option 
> "-rmr <path>". Again, for each file.
> Changed that to dstfs.delete(path, true)

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