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From Jason Yang <lin.yang.ja...@gmail.com>
Subject Re: what's the default reducer number?
Date Tue, 11 Sep 2012 11:36:28 GMT
Hi, Bejoy

Thanks for you reply.

where could I find the default value of mapred.reduce.tasks ? I have
checked the core-site.xml, hdfs-site.xml and mapred-site.xml, but I haven't
found it.

2012/9/11 Bejoy Ks <bejoy.hadoop@gmail.com>

> Hi Lin
>
> The default value for number of reducers is 1
>
> <name>mapred.reduce.tasks</name>
>   <value>1</value>
>
> It is not determined by data volume. You need to specify the number of
> reducers for your mapreduce jobs as per your data volume.
>
> Regards
> Bejoy KS
>
> On Tue, Sep 11, 2012 at 4:53 PM, Jason Yang <lin.yang.jason@gmail.com>wrote:
>
>> Hi, all
>>
>> I was wondering what's the default number of reducer if I don't set it in
>> configuration?
>>
>> Will it change dynamically according to the output volume of Mapper?
>>
>> --
>> YANG, Lin
>>
>>
>


-- 
YANG, Lin

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