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From Rasit OZDAS <rasitoz...@gmail.com>
Subject Re: Running Map and Reduce Sequentially
Date Sat, 14 Feb 2009 00:11:52 GMT
This is the case when you have only 1 reducer.
If it doesn't have any side effects for you..


2009/2/14 Kris Jirapinyo <kjirapinyo@biz360.com>:
> Is there a way to tell Hadoop to not run Map and Reduce concurrently?  I'm
> running into a problem where I set the jvm to Xmx768 and it seems like 2
> mappers and 2 reducers are running on each machine that only has 1.7GB of
> ram, so it complains of not being able to allocate memory...(which makes
> sense since 4x768mb > 1.7GB).  So, if it would just finish the Map and then
> start on Reduce, then there would be 2 jvm's running on one machine at any
> given time and thus possibly avoid this out of memory error.

M. Raşit ÖZDAŞ

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