Thank you! Just to confirm. Consider a JVM (that is being reused), has
to reduce K1,{V11,V12,V13..} and K2,{V21,V22,V23,}. Then the
configure and close methods are called once each for both K1,{V11,...}
and K2,{V2,}?
Is my understanding correct?
Once again, there is no combiner, and it makes sense that it is not called.
Thank you
Saptarshi
On Mon, Jun 22, 2009 at 10:55 PM, jason hadoopjason.had...@gmail.com wrote:
configure and close are run for each task, mapper and reducer. The configure
and close are NOT run on the combiner class.
On Mon, Jun 22, 2009 at 9:23 AM, Saptarshi Guha saptarshi.g...@gmail.com
wrote:
Hello,
In a mapreduce job, a given map JVM will run N map tasks. Are the
configure and close methods executed for every one of these N tasks?
Or is configure executed once when the JVM starts and the close method
executed once when all N have been completed?
I have the same question for the reduce task. Will it be run before
for every reduce task? And close is run when all the values for a
given key have been processed?
We can assume there isn't a combiner.
Regards
Saptarshi
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