FAQ
[ https://issues.apache.org/jira/browse/HADOOP-2429?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12645404#action_12645404 ]

Owen O'Malley commented on HADOOP-2429:
---------------------------------------

The API in C++ is completely byte-based. It uses std::string, but treats them as raw byte containers. (The C++ interface for map/reduce does not use JNI. It uses an external process that communicates via a socket.)
The lowest level map-reduce APIs should be byte oriented
--------------------------------------------------------

Key: HADOOP-2429
URL: https://issues.apache.org/jira/browse/HADOOP-2429
Project: Hadoop Core
Issue Type: Improvement
Components: mapred
Reporter: eric baldeschwieler

As discussed here:
https://issues.apache.org/jira/browse/HADOOP-1986#action_12551237
The templates, serializers and other complexities that allow map-reduce to use arbitrary types complicate the design and lead to lots of object creates and other overhead that a byte oriented design would not suffer. I believe the lowest level implementation of hadoop map-reduce should have byte string oriented APIs (for keys and values). This API would be more performant, simpler and more easily cross language.
The existing API could be maintained as a thin layer on top of the leaner API.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.

Search Discussions

Discussion Posts

Previous

Related Discussions

Discussion Navigation
viewthread | post
posts ‹ prev | 2 of 2 | next ›
Discussion Overview
groupcommon-dev @
categorieshadoop
postedNov 3, '08 at 8:17p
activeNov 6, '08 at 6:02a
posts2
users1
websitehadoop.apache.org...
irc#hadoop

1 user in discussion

Owen O'Malley (JIRA): 2 posts

People

Translate

site design / logo © 2022 Grokbase