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Hadoop >> mail # user >> How to Set No of Mappers in program


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unmesha sreeveni 2013-11-13, 04:21
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unmesha sreeveni 2013-11-13, 05:00
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Dieter De Witte 2013-11-13, 09:25
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Re: How to Set No of Mappers in program
number of mappers depend on the number of dfs blocks you file spans across
, considering standard file input formatter. unlike reducers , where you
configure as how many reducers you want for your job.

thanks,
Rahul
On Tue, Nov 12, 2013 at 9:00 PM, unmesha sreeveni <[EMAIL PROTECTED]>wrote:

> For my 5000 recorded file .. How many mappers will be running?
>
> And is there a way to know how my files are splited?
>
>
> On Wed, Nov 13, 2013 at 9:51 AM, unmesha sreeveni <[EMAIL PROTECTED]>wrote:
>
>> How to set the no of mappers?
>>
>> I am running a job with input file of 5000 records.but actually it is a
>> small file for hadoop..but i need to know whether it can be exceuted faster.
>>
>> when i tried to run my job it took nearly 30 min to complete my job...
>> why so?
>>
>> If i set my mappers to a lower count whether any reflection happens to my
>> job performance?
>>
>> --
>> *Thanks & Regards*
>>
>> Unmesha Sreeveni U.B
>>
>> *Junior Developer*
>>
>>
>>
>
>
> --
> *Thanks & Regards*
>
> Unmesha Sreeveni U.B
>
> *Junior Developer*
>
>
>
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB