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From Sindhu Hosamane <sindh...@gmail.com>
Subject Re: Ideal number of mappers and reducers to increase performance
Date Sun, 03 Aug 2014 20:51:53 GMT

I am not coding in mapreduce. I am running my cascalog queries on hadoop cluster(1 node )
on data of size 280MB. So all the config settings has to be made on hadoop cluster itself.
As you said , i set the values of mapred.tasktracker.map.tasks.maximum =4  
 and mapred.tasktracker.reduce.tasks.maximum = 4  
and then kept tuning it up ways and down ways  like below 
(4+4)   (5+3) (6+2) (2+6) (3+5) (3+3 ) (10+10)

But all the time performance remains same .
Everytime, inspite whatever combination of mapred.tasktracker.map.tasks.maximum and mapred.tasktracker.reduce.tasks.maximum
i use -  produces same execution time .

Then when the above things failed i also tried mapred.reduce.tasks = 4 
still results are same. No reduction in execution time.

What other things should i set? Also i made sure hadoop is restarted every time after changing
I have attached my conf folder ..please indicate me what should be added where ?
I am really stuck ..Your help would be much appreciated. Thank you .

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