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From Mahadev Konar <maha...@apache.org>
Subject Re: location awareness on RT tasks?
Date Tue, 08 Feb 2011 22:09:45 GMT
Hi Pedro,
  You can read abt the hdfs placement policy at:

http://hadoop.apache.org/common/docs/r0.20.2/hdfs_design.html

thanks
mahadev

On Fri, Feb 4, 2011 at 7:06 AM, Pedro Costa <psdc1978@gmail.com> wrote:
> Hi,
>
> When hadoop is running in cluster, the output of the Reducers are
> saved in HDFS. The MapReduce have also location awareness on where is
> saved the data?
>
> For example, we've TT1 running in Machine1, and TT2 running in
> Machine2. The replication of HDFS is 3. The Reduce Task RT1 is running
> in TT1. So, when the reducer saves output in HDFS, 2 replicas of the
> output goes to TT1 and the third one goes to TT2? Is this what
> happens?
>
> Thanks,
>
> --
> Pedro
>

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