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MapReduce >> mail # user >> Map output files and partitions.

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Re: Map output files and partitions.
Map output files, by which you perhaps mean intermediate data files
for temporary K/V persistence, are stored in IFiles. They do not use
text nor sequence files (historically though, they did use sequence
files at some point).

You can read the IFile's sources at
for more technical details on it. It is very similar to SequenceFiles
in some ways.

On Fri, Dec 14, 2012 at 12:45 PM, Pedro Sá da Costa <[EMAIL PROTECTED]> wrote:
> Hi,
> There only 2 types of map output files, Sequence and Text files. If
> those files are going to be used as input to several reduce tasks,
> they need to be partitioned into blocks. Is there any SEPARATOR bits
> that limits each partition? Can I read a specific partition of a map
> output file? Is there an API for that?
> --
> Best regards,

Harsh J