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From: Mark Desnoyer <mdesnoyer@gmail.com>
Date: Thu, 18 Jun 2009 10:33:25 -0400
Message-ID: <d997e2110906180733v7f76b073vf1158164bdd86c69@mail.gmail.com>
Subject: Re: Getting Task ID inside a Mapper
To: core-user@hadoop.apache.org
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Thanks! I'll try that.

-Mark

On Thu, Jun 18, 2009 at 10:27 AM, Jingkei Ly <Jingkei.ly@detica.com> wrote:

> I think you can use job.getInt("mapred.task.partition",-1) to get the
> mapper ID, which should be the same for the mapper across task reruns.
>
> -----Original Message-----
> From: Piotr Praczyk [mailto:piotr.praczyk@gmail.com]
> Sent: 18 June 2009 15:19
> To: core-user@hadoop.apache.org
> Subject: Re: Getting Task ID inside a Mapper
>
> Hi
> Why don't you provide a seed of random generator generated outside the
> task
> ? Then when the task fails, you can provide the same value stored
> somewhere
> outside.
> You could use the task configuration to do so.
>
> I don't know anything about obtaining the task ID from within.
>
>
> regards
> Piotr
>
> 2009/6/18 Mark Desnoyer <mdesnoyer@gmail.com>
>
> > Hi,
> >
> > I was wondering if it's possible to get a hold of the task id inside a
> > mapper? I cant' seem to find a way by trolling through the API
> reference.
> > I'm trying to implement a Map Reduce version of Latent Dirichlet
> Allocation
> > and I need to be able to initialize a random number generator in a
> task
> > specific way so that if the task fails and is rerun elsewhere, the
> results
> > are the same. Thanks in advance.
> >
> > Cheers,
> > Mark Desnoyer
> >
>
>
>
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