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From "Kartashov, Andy" <Andy.Kartas...@mpac.ca>
Subject RE: a question on MapReduce
Date Mon, 19 Nov 2012 14:37:07 GMT

Sometimes when I run my MR job I see that Reduce tasks kick in as early as when Map task reached
only about 20%. How can the MR be possibly so sure and start running Reduce at this point?
What if a Mapper  produce more keys that Reduce function already finished with?

Andy Kartashov
IT Architecture, Co-op
1340 Pickering Parkway, Pickering, L1V 0C4
* Phone : (905) 837 6269
* Mobile: (416) 722 1787

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