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Pig, mail # dev - No of reducers


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Re: No of reducers
Thejas M Nair 2011-05-31, 18:41
In pig 0.8 the default number of reducers changed from 1 to a value computed based on input data size -
http://pig.apache.org/docs/r0.8.1/cookbook.html#Use+the+Parallel+Features

-Thejas
On 5/27/11 6:46 AM, "Jonathan Coveney" <[EMAIL PROTECTED]> wrote:

SET default_parallel X; will set the PARALLEL keyword for all parallel
functions (ie set the reducers for the job)

I am not sure how the default is calculated...for a while it was set to 1 I
believe, ostensibly to force people to set it to something more reasonable.

2011/5/27 Harsh J <[EMAIL PROTECTED]>

> The PARALLEL keyword controls the number of reducers used in the job.
> If unspecified, a default number is applied. Is this what you're
> looking for?
>
> On Fri, May 27, 2011 at 3:46 PM, Sudharsan Sampath
> <[EMAIL PROTECTED]> wrote:
> >
> > Hi,
> >
> > Is there a reference on how the number of reducers required for a job is
> calculated?
> >
> > Thanks
> > Sudharsan S
> >
> >
>
>
>
> --
> Harsh J
>

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