Re: the default value for param "mapreduce.reduce.shuffle.input.buffer.percent"

[wzc <wz...@gmail.com>]

hi Sudhakara:
  Thank you for your reply. I've lost the old job information which I
thought "mapreduce.reduce.shuffle.input.buffer.percent" was set to 0.9 in.
I cant make it to read hard coded value from MergeManagerImpl.java. So
maybe I made a mistake.

Thanks.


2014-05-17 1:45 GMT+08:00 sudhakara st <su...@gmail.com>:

> "mapreduce.reduce.shuffle.input.buffer.percent"  paramenter value is going
> go sets by reading the mapred-site.xml, if you not specified value in
> mapred-site.xml it reads value from mapred-default.xml. Its value in
> mapred-default.xml is 0.7. So default value is 0.7. For various reason
> mapreduce.reduce.shuffle.input.buffer.percent is null then it will reads
> hard coded value from the fuction MergeManagerImpl.java as 0.9. I think
> this case never arises, MR always set parameters values by reading
> mapred-default.xml.
>
> Regards,
> Sudhakara
>
>
> On Fri, May 16, 2014 at 8:45 AM, wzc <wz...@gmail.com> wrote:
>
>> Hi,
>>    I find the defualt value for
>> "mapreduce.reduce.shuffle.input.buffer.percent" is 0.7
>> in mapred-default.xml but  0.9 in MergeManagerImpl.java. I wonder which
>> default value should I choose ? I think 0.9 maybe too high ?
>> Any help is appreciated.
>>
>> Thanks.
>>
>>
>
>
> --
>
> Regards,
> ...sudhakara
>
>