hadoop-common-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Doug Cutting (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HADOOP-4640) Add ability to split text files compressed with lzo
Date Wed, 12 Nov 2008 18:11:44 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-4640?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12646985#action_12646985
] 

Doug Cutting commented on HADOOP-4640:
--------------------------------------

> What is our policy on this?

I don't know that we have a clear policy.  In this case, I think it would be fine for the
tests to succeed with a warning if native code is not available.  Ideally we should have tests
that are only run when native code is available.

A few questions:
 - Should the InputFormat require the index, as in your patch, or rather should it degrade
gracefully, so that if indexes do not exist it creates a single split per file?
 - It would be great to have an OutputFormat that creates indexes as files are written.  Is
that possible?


> Add ability to split text files compressed with lzo
> ---------------------------------------------------
>
>                 Key: HADOOP-4640
>                 URL: https://issues.apache.org/jira/browse/HADOOP-4640
>             Project: Hadoop Core
>          Issue Type: Improvement
>          Components: io, mapred
>            Reporter: Johan Oskarsson
>            Assignee: Johan Oskarsson
>            Priority: Trivial
>             Fix For: 0.20.0
>
>         Attachments: HADOOP-4640.patch
>
>
> Right now any file compressed with lzop will be processed by one mapper. This is a shame
since the lzo algorithm would be very suitable for large log files and similar common hadoop
data sets. The compression rate is not the best out there but the decompression speed is amazing.
 Since lzo writes compressed data in blocks it would be possible to make an input format that
can split the files.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message