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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?
Jeff Bean 2013-01-16, 09:20
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

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,