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From Harold Valdivia Garcia <harold.valdi...@upr.edu>
Subject how to read replicated blocks with hdfs api?
Date Thu, 06 Aug 2009 20:20:07 GMT
Hi... I was reading the HDFS code, and I can't find a way to read the
replicated blocks of a block-file.

DFS.getFileBlockLocations returns all blocks of a file
File = block-a, block-b, ..... block-n.

each of these blocks has its replicated blocks. if for instance the
replication factor is 3, how can I retrieve block-a1, block-a2, block-a3 in
parallel from my user code?

I did read DFSClient, DFSClient.DFInputStream to understand how hadoop
retrieves data from blocks, but it is hard.
There is no an easy way to do this?
-- 
******************************************
Harold Dwight Valdivia Garcia
Graduate Student
M.S Computer Engineering
University of Puerto Rico, Mayaguez Campus
******************************************

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