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RE: Assigning the same partition number to the mapper output
If you are using TextOutputFormat for your job,  getRecordWriter() (i.e RecordWriter<K, V> org.apache.hadoop.mapreduce.lib.output.TextOutputFormat.getRecordWriter(TaskAttemptContext job) throws IOException, InterruptedException) method uses  FileOutputFormat.getDefaultWorkFile() for generating the file names. It uses $output/_temporary/$taskid/part-[mr]-$id format to generate the o/p path name for task in temp dir.

http://hadoop.apache.org/docs/current/api/org/apache/hadoop/mapreduce/lib/output/FileOutputFormat.html#getDefaultWorkFile(org.apache.hadoop.mapreduce.TaskAttemptContext, java.lang.String)
If you want to change the o/p path name for the task, you need to override this method for your Job accordingly whichever you want.

If you want change only base output name for the output file(default value is "part"), you can use "mapreduce.output.basename" configuration.

  Devaraj K

From: Maysam Hossein Yabandeh [mailto:[EMAIL PROTECTED]]
Sent: 12 June 2013 21:16
Cc: Maysam Hossein Yabandeh
Subject: Assigning the same partition number to the mapper output


I was wondering if it is possible in hadoop to assign the same partition numbers to the map outputs. I am running a map-only job (with zero reducers) and hadoop shuffles the partitions in the output: i.e. input/part-m-0000X is processed by task number Y and hence generates output/part-m-0000Y (where X != Y).


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