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courses:mapreduce-tutorial:step-3 [2012/01/25 21:33]
straka 		courses:mapreduce-tutorial:step-3 [2012/01/25 21:50]
straka
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 The simplest Hadoop job consists of a mapper only.  The input data is divided in several parts, every processed by an independent mapper, and the results are collected in one directory, one file per mapper. The simplest Hadoop job consists of a mapper only.  The input data is divided in several parts, every processed by an independent mapper, and the results are collected in one directory, one file per mapper.
  
-The Hadoop framework handles+The Hadoop framework silently handles failures. If a mapper task fails, another is executed and the input of the failed attempt is discarded.
  
 ===== Example Perl mapper ===== ===== Example Perl mapper =====
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 ===== Exercise ===== ===== Exercise =====
  
-To check that your Hadoop environment works, try running a MR job on ''/home/straka/wiki/cs-text'', which outputs only articles with names beginning with a (ignoring the case).+To check that your Hadoop environment works, try running a MR job on ''/home/straka/wiki/cs-text'', which outputs only articles with names beginning with an ''A'' (ignoring the case).
  
 {{.:step-3-solution.txt|Solution.pl}} {{.:step-3-solution.txt|Solution.pl}}
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