Hello, On Mon, Feb 14, 2011 at 8:51 PM, Pedro Costa <psdc1...@gmail.com> wrote: > Hi, > > 1 - The map output files are always of the type SequenceFileFormat?
If you mean the Map-intermediate files, then no - they're IFiles. Otherwise, if your OutputFormat is set to a SequenceFileOutputFormat, then yes these type of files would be created. Map-Reduce intermediate files are of the IFile format. It's not part of the public API, but you may read its implementation in src/java/org/apache/hadoop/mapred/IFile.java. SequenceFiles are almost similar, but are built for better K-V file operations such as skipping over keys, etc. which is not essentially required in case of partitioned-and-sorted-data-containing IFiles. -- Harsh J www.harshj.com
