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Pig, mail # user - How can I split the data with more reducers?


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Re: How can I split the data with more reducers?
Haitao Yao 2012-09-16, 09:18
The map output of the first MR job is over 500MB, and only 1 reducer processes it. So OutOfMemoryError is caused.

After set the child memory to 1GB, the first job succeeded. But most of our jobs does not need that much memory. 512MB is enough if I can set the reducer to more than 1.
Haitao Yao
[EMAIL PROTECTED]
weibo: @haitao_yao
Skype:  haitao.yao.final

On 2012-9-16, at 下午5:05, Haitao Yao wrote:

> here's the explain result compressed.(The apache mail server does not allow big attachments.)
> <explain.tar.gz>
>
>
> Haitao Yao
> [EMAIL PROTECTED]
> weibo: @haitao_yao
> Skype:  haitao.yao.final
>
> On 2012-9-16, at 下午4:41, Dmitriy Ryaboy wrote:
>
>> Still would like to see the script or the explain plan..
>>
>> D
>>
>> On Sat, Sep 15, 2012 at 7:50 PM, Haitao Yao <[EMAIL PROTECTED]> wrote:
>>> No, I also thought it is a mapper , but It surely is a reducer. all the mappers succeeded and the reducer failed.
>>>
>>>
>>>
>>> Haitao Yao
>>> [EMAIL PROTECTED]
>>> weibo: @haitao_yao
>>> Skype:  haitao.yao.final
>>>
>>> On 2012-9-16, at 上午10:08, Haitao Yao wrote:
>>>
>>>> Hi,
>>>>      I 'v encountered a problem: the job failed because of POSplit retained too much memory in the reducer. How can I specify more reducers for the spill?
>>>>
>>>>      Here's the screen snapshot of the Heap dump.
>>>>      <aa.jpg>
>>>>
>>>>
>>>> And here's the snippet of my split script:
>>>>
>>>>      split RawData into AURawData if type == 2, NURawData if type == 1, InRawData if type == 9, GCData if type == 61, HCData if type == 71, TutorialRawData if type == 3 or t    ype == 15;
>>>>
>>>> There's 3 similar split clause in my script. The reducer count is always 1. How can I increase it?
>>>>
>>>> Thanks.
>>>>
>>>>
>>>>
>>>> Haitao Yao
>>>> [EMAIL PROTECTED]
>>>> weibo: @haitao_yao
>>>> Skype:  haitao.yao.final
>>>>
>>>
>