Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
MapReduce >> mail # user >> Re: which is better : form reducer or Driver


Copy link to this message
-
Re: which is better : form reducer or Driver
ok i will check them in both ways :)
On Wed, Nov 6, 2013 at 2:10 PM, Chris Mawata <[EMAIL PROTECTED]> wrote:

>  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]>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/> *
>
>
>
--
*Thanks & Regards*

Unmesha Sreeveni U.B

*Junior Developer*

*Amrita Center For Cyber Security*
* Amritapuri.www.amrita.edu/cyber/ <http://www.amrita.edu/cyber/>*