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From "Qin Gao" <q...@cs.cmu.edu>
Subject Re: is combiner output written to disk?
Date Mon, 22 Sep 2008 04:15:31 GMT
I think it will be written to disk. There will be no difference in output
format or flow with or without combiner.

On Mon, Sep 22, 2008 at 12:08 AM, Sandy <snickerdoodle08@gmail.com> wrote:

> Just a quick clarification:
>
> The combiner function acts as an optimization between the map and the
> reduce
> phases. Is the output of the combiner phase stored in memory before being
> handed to reduce? Or is it written to disk and subsequently read from disk
> by the reduce phase?
>
>
> Thanks in advance,
>
> -SM
>

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