HDFS Forum

Question on how MapReduce works?

  • #27802

    I am trying to understand the order in which the following steps works. My understanding in general is that they happen in the following order (although Combiner can also happen during the reduce phase too.)


    Esp. confused about when Combiner, Partitioner and Shuffle/Sort happens.

    Any anyone confirm? I found this question among the Hortonworks sample test questions.

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  • #27803

    Hi Nietzsche,

    In my quick read over the docs that I can find, it looks like you have the order correct.


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