[
https://issues.apache.org/jira/browse/MAPREDUCE-1126?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12805679#action_12805679
]
Doug Cutting commented on MAPREDUCE-1126:
-----------------------------------------
Which Avro serializer? Avro includes three different mappings from in-memory to
binary representations, and applications can add more. In generic, a
java.lang.String represents an enum symbol, while in reflect it represents a
string.
And do we really want to privilege Avro here? It should be possible to use
Thrift too, and intermix the two within a single job. A Long in the input might
be a part of Thrift union, and a Long in the output may use Avro.
> shuffle should use serialization to get comparator
> --------------------------------------------------
>
> Key: MAPREDUCE-1126
> URL: https://issues.apache.org/jira/browse/MAPREDUCE-1126
> Project: Hadoop Map/Reduce
> Issue Type: Improvement
> Components: task
> Reporter: Doug Cutting
> Assignee: Aaron Kimball
> Fix For: 0.22.0
>
> Attachments: MAPREDUCE-1126.2.patch, MAPREDUCE-1126.3.patch,
> MAPREDUCE-1126.4.patch, MAPREDUCE-1126.5.patch, MAPREDUCE-1126.6.patch,
> MAPREDUCE-1126.patch
>
>
> Currently the key comparator is defined as a Java class. Instead we should
> use the Serialization API to create key comparators. This would permit,
> e.g., Avro-based comparators to be used, permitting efficient sorting of
> complex data types without having to write a RawComparator in Java.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
