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http://issues.apache.org/jira/browse/HADOOP-93?page=comments#action_12370894 ] 

Owen O'Malley commented on HADOOP-93:
-------------------------------------

>From what I've seen, it is always 32M fragments, but that is still 300k input 
>splits/maps, which is a lot. We'd like to be able to drop that by an order of 
>magnitude. (I think in this case that the input splitter never finished, so we 
>don't know.)

> allow minimum split size configurable
> -------------------------------------
>
>          Key: HADOOP-93
>          URL: http://issues.apache.org/jira/browse/HADOOP-93
>      Project: Hadoop
>         Type: Bug
>     Reporter: Hairong Kuang
>  Attachments: hadoop-93.fix
>
> The current default split size is the size of a block (32M) and a 
> SequenceFile sets it to be SequenceFile.SYNC_INTERVAL(2K). We currently have 
> a Map/Reduce application working on crawled docuements. Its input data 
> consists of 356 sequence files, each of which is of a size around 30G. A 
> jobtracker takes forever to launch the job because it needs to generate 
> 356*30G/2K map tasks!
> The proposed solution is to let the minimum split size configurable so that 
> the programmer can control the number of tasks to generate.

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