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From Matt Tanquary <matt.tanqu...@gmail.com>
Subject Re: Setting num reduce tasks
Date Thu, 21 Oct 2010 21:39:29 GMT
I used the new API. I just tried the job.setNumReduceTasks() method and it
seems to be working.

Thanks Alex and Ed for helping me!

On Thu, Oct 21, 2010 at 2:32 PM, Alex Kozlov <alexvk@cloudera.com> wrote:

> It looks like you do not pass the Configuration object correctly.  Do you
> use old or new (mapreduce) API?  Do you have something like
>
> Job job = new Job(conf, "My job with " + conf.get("mapred.reduce.tasks") +
> "
> reducers");
>
> to create the job?  Is it OK to share you job creation code?
>
> Alex K
>
> On Thu, Oct 21, 2010 at 2:25 PM, Matt Tanquary <matt.tanquary@gmail.com
> >wrote:
>
> > Hi Alex,
> >
> > Yes, I confirmed from those locations that the job is setting the
> reducers
> > to 1.
> >
> > Thanks
> >
> > On Thu, Oct 21, 2010 at 1:45 PM, Alex Kozlov <alexvk@cloudera.com>
> wrote:
> >
> > > Hi Matt, it might be that the parameter does not end up in the final
> > > configuration for a number of reasons.  Can you check the job config
> xml
> > in
> > > jt:/var/log/hadoop/history or in the JT UI and see what the
> > > mapred.reduce.tasks setting is?  -- Alex K
> > >
> > > On Thu, Oct 21, 2010 at 1:39 PM, Matt Tanquary <
> matt.tanquary@gmail.com
> > > >wrote:
> > >
> > > > I am using the following to set my number of reduce tasks, however
> when
> > I
> > > > run my job it's always using just 1 reducer.
> > > >
> > > > conf.setInt("mapred.reduce.tasks", 20);
> > > >
> > > > 1 reducer will never finish this job. Please help me to understand
> why
> > > the
> > > > setting I choose is not used.
> > > >
> > > > Thanks,
> > > > -M@
> > > >
> > >
> >
> >
> >
> > --
> > Have you thanked a teacher today? ---> http://www.liftateacher.org
> >
>



-- 
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