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From Sandy <snickerdoodl...@gmail.com>
Subject Re: is combiner output written to disk?
Date Mon, 22 Sep 2008 04:27:26 GMT
Thank you for your swift response!

-SM

On Sun, Sep 21, 2008 at 11:15 PM, Qin Gao <qing@cs.cmu.edu> wrote:

> 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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