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From Saptarshi Guha <saptarshi.g...@gmail.com>
Subject Number of combiner threads in a JVM
Date Tue, 16 Mar 2010 21:41:33 GMT
If a combiner is set, the combiner might run in parallel with the map
or the reducer.
I say might because it is not guaranteed that the combiner will run.

Q: How many combiner threads in a JVM are run in parallel? One? So,
for example, suppose
a map is processing its tasks will there be a single combiner thread
(if at all) running in parallel?

Thank you

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