Hi,
Thanks for your answer.
I used these parameters. But they seem to limit only the number of
parallel maps and parallel reduces separately. They do not prevent
the scheduler from schedule one map and one reduce on the same task
tracker in parallel.
But that's the problem I'm trying to solve. Having at most one task
running on a task tracker at any time (never one map and one reduce
together on one task tracker).
Any idea how to do this?
Oliver
Chandraprakash Bhagtani wrote:
Hi Oliver,
yes you can control number of tasks per tasktracker by
mapred.tasktracker.{map|reduce}.tasks.maximum.
in your case
1. you might not have restarted the cluster after changing hadoop conf xml.
2. your input data might be very less (only one data block might be there)
therefore only one map task is launched.
