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From Allen Wittenauer <awittena...@linkedin.com>
Subject Re: Hadoop does not follow my setting
Date Thu, 22 Apr 2010 19:44:28 GMT

On Apr 22, 2010, at 11:46 AM, He Chen wrote:

> Yes, but if you have more mappers, you may have more waves to execute. I
> mean if I have 110 mappers for a job and I only have 22 cores. Then, it will
> execute 5 waves approximately, If I have only 22 mappers, It will save the
> overhead time.

But you'll sacrifice data locality, which means that instead of testing the cpu, you'll be
testing cpu+network.

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