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MapReduce, mail # user - Re: which is better : form reducer or Driver


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Re: which is better : form reducer or Driver
Chris Mawata 2013-11-06, 08:40
Try it both ways and look at the numbers. Measurement is the ultimate
way to get the answer.
My bet: The difference is so small I would worry about where if makes
your code more maintainable than tuning before coding.
Chris
On 11/5/2013 9:59 PM, unmesha sreeveni wrote:
> i am dealing with multiple mappers and 1 reducer. so which is best?
>
>
> On Tue, Nov 5, 2013 at 6:28 PM, Chris Mawata <[EMAIL PROTECTED]
> <mailto:[EMAIL PROTECTED]>> wrote:
>
>     If you have multiple reducers you are doing it in parallel while
>     in the driver it is surely single threaded so my bet would be on
>     the reducers.
>
>     Chris
>
>
>     On 11/5/2013 6:15 AM, unmesha sreeveni wrote:
>>     I am emiting 'A' value and 'B' value from reducer.
>>
>>     I need to do further calculations also.
>>     which is a better way?
>>     1. Do all remamining computations within reducer , after emiting
>>     or
>>     2.Do remaining computation In driver: read A and B value from
>>     part file and do further computations.
>>
>>     Pls suggest a better way.
>>
>>     --
>>     /Thanks & Regards/
>>     /
>>     /
>>     Unmesha Sreeveni U.B/
>>     /
>>     /Junior Developer
>>     /
>>     /Amrita Center For Cyber Security
>>     /
>>     /
>>     Amritapuri.
>>
>>     www.amrita.edu/cyber/ <http://www.amrita.edu/cyber/>
>>     /
>
>
>
>
> --
> /Thanks & Regards/
> /
> /
> Unmesha Sreeveni U.B/
> /
> /Junior Developer
> /
> /Amrita Center For Cyber Security
> /
> /
> Amritapuri.
>
> www.amrita.edu/cyber/ <http://www.amrita.edu/cyber/>
> /