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From 王志强 <wangzhiqi...@360.cn>
Subject 答复: Why hadoop is spawing two map over file size 1.5 KB ?
Date Thu, 14 Mar 2013 16:04:48 GMT
please check parameter "mapred.map.tasks" is equals to 2?
________________________________
发件人: Yanbo Liang [yanbohappy@gmail.com]
发送时间: 2013年3月14日 23:11
收件人: user@hadoop.apache.org
主题: Re: Why hadoop is spawing two map over file size 1.5 KB ?

I guess may be one of them is the speculative execution.
You can check the parameter "mapred.map.tasks.speculative.execution" to ensure whether it
is allowed speculative execution.
You can get the precise information that whether it is speculative map task from the tasktracker
log.

2013/3/12 samir das mohapatra <samir.helpdoc@gmail.com<mailto:samir.helpdoc@gmail.com>>
Hi All,
  I have very fundamental doubt, I have file having size 1.5KB and block size is default block
size, But i could see two mapper it got creted during the Job. Could you please help  to get
whole picture why it is .

Regards,
samir.

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