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From Nick Cen <cenyo...@gmail.com>
Subject Re: will record having same key be sent to reducer at the same time
Date Mon, 23 Feb 2009 10:50:29 GMT
Thanks.

2009/2/23 james warren <james@rockyou.com>

> Hi Nick -
> While your reducers may be running concurrently with your mappers, they
> will
> not begin the "sort" and "reduce" steps until all map tasks have completed.
>  Once they actually begin the reduce stage, they will have received all
> values for a given key.
>
> cheers,
> -jw
>
> On Mon, Feb 23, 2009 at 1:00 AM, Nick Cen <cenyongh@gmail.com> wrote:
>
> > Hi all,
> >
> > If i have a bunch of value that have the same key, and i have more then
> one
> > reducer running, which guarantee both mapper and reducer are running
> > concurently. Will all these value be send to the reducer at the same
> time?
> > Thx
> >
> > --
> > http://daily.appspot.com/food/
> >
>



-- 
http://daily.appspot.com/food/

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