they are the places to check. a job can itself over-ride the number of mappers and reducers. for example, using streaming, i often state the number of mappers and reducers i want to use:
-jobconf mapred.reduce.tasks=30 this would tell hadoop to use 30 reducers, for example. if you don't have enough memory to run a mapper then you will see error messages logged somewhere. perhaps it might be useful to check all the logs Miles 2009/4/22 javateck javateck <[email protected]>: > I want to have something to clarify, for the max task slots, are these > places to check: > 1. hadoop-site.xml > 2. the specific job's job.conf which can be retrieved though the job, for > example, logs/job_200904212336_0002_conf.xml > > Any other place to limit the task map counts? > > In my case, it's strange, because I set 10 for " > mapred.tasktracker.map.tasks.maximum", and I check the job's conf is also > 10, but actual hadoop is just using 2 map jobs. > > > On Tue, Apr 21, 2009 at 1:20 PM, javateck javateck <[email protected]>wrote: > >> 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 >> > -- The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.
