Hi Pedro, The format is called IFile. Check out the source for more info on the format - it's fairly simple. The partition starts are recorded in a separate index file next to the output file.
I don't think you'll find significant docs on this format since it's MR-internal - the code is your best resource. -Todd On Fri, Nov 4, 2011 at 8:37 AM, Pedro Costa <[email protected]> wrote: > Hi, > > I'm trying to understand the structure of the map output file. Here's an > example of a mapoutput file that contains 2 partitions: > > [code] > <FF><FF><FF><FF>^@^@716banana banana apple banana carrot carrot apple > banana 0apple carrot carrot carrot banana carrot carrot 5^N4carrot apple > carrot apple apple carrot banana apple ^Mbanana apple <FF><FF><DF>|<8E><B7> > [/code] > > 1 - I would like to understand what are the ASCII characters parts. What > they means? > > 2 - What type of file is a map output? Is it a SequenceFileOutputFormat, or > a TextOutputFormat? > > 3 - I've a small program that runs independently of the MR that has the > goal to digest each partition and give the correspondent hash. How do I > know where each partition starts? > > > -- > Thanks, > PSC > -- Todd Lipcon Software Engineer, Cloudera
