right, I set it in hadoop-site.xml before starting the whole hadoop processes, I have one job running fully utilizing the 10 map tasks, but subsequent queries are only using 2 of them, don't know why. I have enough RAM also, no paging out is happening, I'm running on 0.18.3. Right now I put all processes on one machine, namenode, datanode, jobtracker, tasktracker, I have a 2*4core CPU, and 20GB RAM.
On Tue, Apr 21, 2009 at 1:25 PM, Koji Noguchi <knogu...@yahoo-inc.com>wrote: > This is a cluster config and not a per job config. > > So this has to be set when the mapreduce cluster first comes up. > > Koji > > > -----Original Message----- > From: javateck javateck [mailto:javat...@gmail.com] > Sent: Tuesday, April 21, 2009 1:20 PM > To: core-user@hadoop.apache.org > Subject: mapred.tasktracker.map.tasks.maximum > > I set my "mapred.tasktracker.map.tasks.maximum" to 10, but when I run a > task, it's only using 2 out of 10, any way to know why it's only using > 2? > thanks >
