I am struggling to control the behavior of the framework. The first problem is simple: I want to run many simultaneous mapper tasks on each node. I've scoured the forums, done the obvious, and I still typically get only 2 tasks per node at execution time. If it is a big job, sometimes I see 3. Note that the administrator reports 40 Tasks/Node in the config, but the most I've ever seen running is 3 (and this with a single input file of 10,000 records, magically yielding 443 maps).
And magically is the next issue. I want to fine tune control the InputFile, Input # records, to maps relationship. For my immediate problem, I want to use a single input file with a number of records yielding the exact same number of maps (all kicked off simultaneously BTW). Since I did not get this behavior with the standard InputFileFormat, I created my own input format class and record reader, and am now getting the "1 file with n recs to nmaps" relationship.... but the problem is that I am not even sure why.... Any guidance appreciated.
