hadoop-common-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Owen O'Malley (JIRA)" <j...@apache.org>
Subject [jira] Updated: (HADOOP-474) support compressed text files as input and output
Date Fri, 08 Sep 2006 07:33:23 GMT
     [ http://issues.apache.org/jira/browse/HADOOP-474?page=all ]

Owen O'Malley updated HADOOP-474:

    Attachment: text-gz-2.patch

This patch extends the previous patch:
  1. the properties are added to the hadoop-default.xml
  2. the SequenceFileOutputFormat now uses the same JobConf methods for determining whether
to compress the output and which codec to use
  3. cleaned up the out of date TODOs in the SequenceFile stuff
  4. created public static methods in CompressionCodecFactory to set/get the set of codecs
into a Configuration
  5. created public static methods in SequenceFileOutputFormat to set/get the CompressionType.
Arguably, these should be in SequenceFile itself

I think having the [gs]etCompressOutput methods in JobConf is reasonable since they are intended
to be used by all of the OutputFormats.

> support compressed text files as input and output
> -------------------------------------------------
>                 Key: HADOOP-474
>                 URL: http://issues.apache.org/jira/browse/HADOOP-474
>             Project: Hadoop
>          Issue Type: Improvement
>          Components: mapred
>    Affects Versions: 0.5.0
>            Reporter: Owen O'Malley
>         Assigned To: Owen O'Malley
>             Fix For: 0.6.0
>         Attachments: text-gz-2.patch, text-gz.patch
> I'd like TextInputFomat and TextOutputFormat to automatically compress and uncompress
text files when they are read and written. Furthermore, I'd like to be able to use custom
compressors as defined in HADOOP-441. Therefore, I propose:
> Adding a map of compression codecs in the server config files:
> io.compression.codecs = "<suffix>=<codec class>,..."
> so the default would be something like:
> <property>
>   <name>io.compression.codecs</name>
>   <value>.gz=org.apache.hadoop.io.GZipCodec,.Z=org.apache.hadoop.io.ZipCodec</value>
>   <description>A list of file suffixes and the codecs for them.</description>
> </property>
> note that the suffix can include multiple "." so you could support suffixes like ".tar.gz",
but they are just treated as literals against the end of the filename.
> If the TextInputFormat is dealing with such a file, it:
>   1. makes a single split
>   2. decompresses automatically
> On the output side, if mapred.output.compress is true, then TextOutputFormat would use
a new property mapred.output.compression.codec that would define the codec to use to compress
the outputs,  defaulting to gzip. 

This message is automatically generated by JIRA.
If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira


View raw message