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Subject: Re: how to make different mappers execute different processing on
 same data ?
From: Mehmet Tepedelenlioglu <mehmetsino@gmail.com>
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 <CAE636z-HDOGgfa=m_qtETiYocb-G+RotWBOdCzHOGK4M56PfZA@mail.gmail.com>
Date: Mon, 10 Sep 2012 21:01:34 -0700
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 <CAE636z-HDOGgfa=m_qtETiYocb-G+RotWBOdCzHOGK4M56PfZA@mail.gmail.com>
To: user@hadoop.apache.org

If you have n processes to evaluate, make a reducer that calls the =
process i when it receives key i, 1<=3Di<=3Dn. Either replicate the data =
for the n reducers, or cache it for it to be read on the reducer side. =
The reducers will output the process id i and the performance.=20


On Sep 10, 2012, at 8:25 PM, Jason Yang wrote:

> Hi, all
>=20
> I've got a question about how to make different mappers execute =
different processing on a same data?=20
>=20
> Here is my scenario:
> I got to process a data, however, there multiple choices to process =
this data and I have no idea which one is better, so I was thinking that =
maybe I could execute multiple mappers, in which different processing =
solution is applied, and eventually the best one is chosen according to =
some evaluation functions.
>=20
> But I'm not sure whether this could be done in MapReduce.
>=20
> Any help would be appreciated.
>=20
> --=20
> YANG, Lin
>=20