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From john smith <js1987.sm...@gmail.com>
Subject Doubt in HBase
Date Thu, 20 Aug 2009 16:42:36 GMT
Hi all ,

I have one small doubt . Kindly answer it even if it sounds silly.

Iam using Map Reduce in HBase in distributed mode .  I have a table which
spans across 5 region servers . I am using TableInputFormat to read the data
from the tables in the map . When i run the program , by default how many
map regions are created ? Is it one per region server or more ?

Also after the map task is over.. reduce task is taking a bit more time . Is
it due to moving the map output across the regionservers? i.e, moving the
values of same key to a particular reduce phase to start the reducer? Is
there any way i can optimize the code (e.g. by storing data of same reducer
nearby )

Thanks :)

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