This property applies to a tasktraker rather that an individual job. Therefore it needs to be set in the mapred-site.xml and the daemon restarted.
-Joey On Jul 1, 2011 7:01 PM, <praveen.pe...@nokia.com> wrote: > Are you sure? AFAIK all mapred.xxx properties can be set via job config. I also read on yahoo tutorial that this property can be either set in hadoop-site.XML or job config. May be someone can confirm this who have really used this property. > > Praveen > > On Jul 1, 2011, at 4:46 PM, "ext Anthony Urso" <antho...@cs.ucla.edu> wrote: > >> On Fri, Jul 1, 2011 at 1:03 PM, <praveen.pe...@nokia.com> wrote: >>> Hi all, >>> >>> I am using hadoop 0.20.2. I am setting the property >>> mapred.tasktracker.map.tasks.maximum = 4 (same for reduce also) on my job >>> conf but I am still seeing max of only 2 map and reduce tasks on each node. >>> I know my machine can run 4 maps and 4 reduce tasks in parallel. Is this a >>> bug in 0.20.2 or am I doing something wrong? >>> >>> >> >> If I remember correctly, you have to set this in your hadoop-site.xml >> and restart your job tracker and task trackers. >> >>> >>> Configuration conf = new Configuration(); >>> >>> conf.set("mapred.tasktracker.map.tasks.maximum", "4"); >>> >>> conf.set("mapred.tasktracker.reduce.tasks.maximum", "4"); >>> >>> >>> >>> Thanks >>> >>> Praveen