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From "momina khan" <momina.a...@gmail.com>
Subject do maps explicitly finish before reduces begin in hadoop
Date Mon, 03 Mar 2008 11:09:51 GMT
hi all,

as seen in the video lectures from google their map reduce ensures
that all maps finish before reduces begin ... their reason for
ensuring this is that not all reduce functions are not necessarily
idempotent....
i just wanted to confirm whether hadoop too follows the same
philosophy ? do all maps end and then reduces begin or can they go on
in parallel cause that is the impression you get from the hadoop code!

cheers
momina

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