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From Apache Wiki <wikidi...@apache.org>
Subject [Lucene-hadoop Wiki] Update of "HadoopMapReduce" by DougCutting
Date Wed, 19 Apr 2006 15:36:03 GMT
Dear Wiki user,

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The following page has been changed by DougCutting:

  less bits to output to disk and read from disk.
  == Reduce ==
+ When a reduce task starts its input is scattered in many files, across all nodes where map
tasks ran. If run in
- When a reduce task starts it will have its input scattered in
- several files possibly on several DFS nodes. If run in
  distributed mode these need to be first copied to the local
  filesystem in a ''copy phase'' (see [http://svn.apache.org/viewcvs.cgi/lucene/hadoop/trunk/src/java/org/apache/hadoop/mapred/ReduceTaskRunner.java?view=markup

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