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MapReduce, mail # user - running a job without user


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Re: running a job without user
Alejandro Abdelnur 2011-03-11, 07:31
Sagar,

Set the following property in your JobConf (or using -D)

*  mapred*.*reduce*.*tasks=0*
*
*

That should do the trick.
Alejandro
***
*
On Fri, Mar 11, 2011 at 1:53 PM, Sagar Kohli <[EMAIL PROTECTED]>wrote:

>  Hi ,
>
>
>
> I am trying to run a job which does not require reducer, I commented out
> the reducer configuration from the job, but now its throwing following error
>
>
>
> *java.lang.ClassCastException*: class java.nio.ByteBuffer
>
>       at java.lang.Class.asSubclass(Unknown Source)
>
>       at org.apache.hadoop.mapred.JobConf.getOutputKeyComparator(*
> JobConf.java:599*)
>
>       at org.apache.hadoop.mapred.MapTask$MapOutputBuffer.<init>(*
> MapTask.java:791*)
>
>       at org.apache.hadoop.mapred.MapTask$NewOutputCollector.<init>(*
> MapTask.java:524*)
>
>       at org.apache.hadoop.mapred.MapTask.runNewMapper(*MapTask.java:613*)
>
>       at org.apache.hadoop.mapred.MapTask.run(*MapTask.java:305*)
>
>       at org.apache.hadoop.mapred.LocalJobRunner$Job.run(*
> LocalJobRunner.java:177*)
>
> 11/03/11 11:19:12 INFO mapred.JobClient:  map 0% reduce 0%
>
>
>
>
>
> *Is it possible to run a job only with mapper??*
>
> * *
>
> * *
>
> Regards
>
> Sagar
>
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