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From Sam Garrett <...@actionx.com>
Subject Reduce Task Clarification
Date Tue, 13 Aug 2013 19:51:13 GMT
I am working on a MapReduce job where I would like to have the output
sorted by a LongWritable value. I read the Anatomy of a MapReduce Run in
the Definitive Guide and it didn't say explicitly whether reduce() gets
called only once per map output key. If it does get called only once I was
thinking that I could use this:
http://hadoop.apache.org/docs/current/api/org/apache/hadoop/mapreduce/Job.html#setSortComparatorClass(java.lang.Class)to
do the sorting.

Thank you for your time.

-- 
Sam Garrett
ActionX, NYC

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