[
https://issues.apache.org/jira/browse/HADOOP-11334?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14225176#comment-14225176
]
Jinghui Wang commented on HADOOP-11334:
---------------------------------------
Not sure if this problem is more appropriate for HADOOP or MAPREDUCE.
> Mapreduce Job Failed due to failure fetching mapper output on the reduce side
> -----------------------------------------------------------------------------
>
> Key: HADOOP-11334
> URL: https://issues.apache.org/jira/browse/HADOOP-11334
> Project: Hadoop Common
> Issue Type: Bug
> Components: io
> Affects Versions: 2.4.1
> Reporter: Jinghui Wang
>
> Running terasort with the following options hadoop jar
> hadoop-mapreduce-examples.jar terasort *-Dio.native.lib.available=false
> -Dmapreduce.map.output.compress=true
> -Dmapreduce.map.output.compress.codec=org.apache.hadoop.io.compress.GzipCodec*
> /tmp/tera-in /tmp/tera-out
> The job failed with the reducer failed to fetching the output from mappers
> (see the following stacktrace). The problem is that in JIRA MAPREDUCE-1784,
> it added support to handle null compressors to default to non-compressed
> output. In this case, when the *io.native.lib.available* is set to true, the
> compressor will be null. However, the decompressor has a Java implementation,
> so when the reducer tries to read the mapper output, it uses the
> decompressor, but the output does not have the Gzip header.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
