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MapReduce >> mail # user >> When reduce tasks start in MapReduce Streaming?


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Re: When reduce tasks start in MapReduce Streaming?
It's called Hadoop Streaming because keys and values are streamed in to
stdin of the script you specify for Hadoop Streaming and then captured via
stdout.

On Wed, Jan 16, 2013 at 1:04 AM, Pedro Sá da Costa <[EMAIL PROTECTED]>wrote:

> So why it's called hadoop streaming, if it doesn't behave like a
> streaming application (The reduces don't receive data as long as it is
> produced by the map tasks)?
>
>
> On 16 January 2013 05:41, Jeff Bean <[EMAIL PROTECTED]> wrote:
> > me property. The reduce method is not called until the mappers are done,
> and
> > the reducers are not scheduled before the threshold set by
> > mapred.reduce.slowstart.completed.maps is reached.
>
>
>
>
> --
> Best regards,
>