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MapReduce >> mail # user >> Setting number of mappers in Teragen


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Re: Setting number of mappers in Teragen
The MR1 teragen's mappers # depends on the total number of rows and
demanded # of maps.

How are you passing -Dmapred.map.tasks=20 (no spaces) exactly? All
generic options must go in before any other options do, so it should
appear right after the word "teragen" in your command.

On Wed, Dec 26, 2012 at 11:49 PM, anil gupta <[EMAIL PROTECTED]> wrote:
> Hi All,
>
> I have 5 worker nodes and i have 4 map slots per node. So, i have 20 map
> slots in my cluster. But when, i start my Teragen job, it only spawns 2
> mappers for entire job. I have even tried using the option
> -Dmapred.map.tasks = 20 . Can anyone tell me how to force teragen to use 20
> mappers for generating the data? I am using cdh4.1.2 with Mapreducev1(Hadoop
> 0.20.2)
> --
> Thanks & Regards,
> Anil Gupta

--
Harsh J