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From jason hadoop <jason.had...@gmail.com>
Subject Re: When is configure and close run
Date Tue, 23 Jun 2009 02:55:57 GMT
configure and close are run for each task, mapper and reducer. The configure
and close are NOT run on the combiner class.

On Mon, Jun 22, 2009 at 9:23 AM, Saptarshi Guha <saptarshi.guha@gmail.com>wrote:

> Hello,
> In a mapreduce job, a given map JVM will run N map tasks. Are the
> configure and close methods executed for every one of these N tasks?
> Or is configure executed once when the JVM starts and the close method
> executed once when all N have been completed?
>
> I have the same question for the reduce task. Will it be run before
> for every reduce task? And close is run when all the values for a
> given key have been processed?
>
> We can assume there isn't a combiner.
>
> Regards
> Saptarshi
>



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