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From "Rahul Sharma (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (CRUNCH-23) PCollection#sort doesn't do a full sort on values
Date Wed, 08 Aug 2012 09:00:22 GMT

    [ https://issues.apache.org/jira/browse/CRUNCH-23?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13430959#comment-13430959
] 

Rahul Sharma commented on CRUNCH-23:
------------------------------------

The patch has been tested using the attached SortTest. The solution works fine but I feel
with the words.txt file the distribution is not perfect. It pushes relatively larger number
of data on the first node.
                
> PCollection#sort doesn't do a full sort on values
> -------------------------------------------------
>
>                 Key: CRUNCH-23
>                 URL: https://issues.apache.org/jira/browse/CRUNCH-23
>             Project: Crunch
>          Issue Type: Bug
>            Reporter: Gabriel Reid
>            Assignee: Rahul Sharma
>         Attachments: 0001-CRUNCH-23-fix-sorting.patch, CRUNCH-23-sorting-issue.patch,
CRUNCH-23-used-TotalOrderpartioner-for-sorting-keys.patch, SortTest.java
>
>
> When a PCollection is sorted (using PCollection#sort), the sorting that is performed
is only per reducer, and not an absolute sort over all values. This means that the values
are not in sorted order if they are iterated over on a materialized collection. It also means
that the sorted files that are output from a sort operation can not be simply concatenated
to come to a single sorted file.

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