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From Doug Cutting <cutt...@apache.org>
Subject Re: Help with MapReduce
Date Thu, 25 May 2006 15:49:21 GMT
Dennis Kubes wrote:
> I am trying to read a MapFile inside mapper and reducer 
> implementations.  So far the only way I have found to do it is by 
> opening a new reader for each map and reduce call.  Is anybody doing 
> something similar and if so is there a way to open a single reader and 
> reuse it across multiple map or reduce calls?

Can't you open it in the configure() implementation?  And close it in 
the close() implementation?

Are you randomly accessing a MapFile from a map() implementation? 
That's not going to scale very well.  MapReduce is designed for 
sequential access.

Doug

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