You can change the no of slots using the following properties in
1. mapred.tasktracker.map.tasks.maximum ( for map slots)
2. mapred.tasktracker.reduce.tasks.maximum (for reduce slot)
On Tue, Jun 5, 2012 at 3:44 AM, Keith Wiley <[EMAIL PROTECTED]> wrote:
> The number of slots corresponds to the number of cores (e.g., a 10-node
> cluster consisting of quad-core cpus has 40 cores and therefore 40 slots).
> The slots can be divided amongst the maps and reduces in a way which
> integer-divides into the cores of a single machine. So if the nodes are
> quad-cores you can do 3:1, 2:2, or 1:3. If the nodes are dual-quad-cores
> (each node has eight cores) you can do 7:1 through 1:7 in any configuration
> you want..........as per my understanding. Others may pipe in to clarify
> some minor point I have missed, I'm unsure.
> On Jun 4, 2012, at 09:06 , kartheek muthyala wrote:
> > Hello all,
> > Can I increase the number of map slots in a machine using some
> > configuration?. I can find configurations for increasing the number of
> > maps and reduce tasks that can run, but didn't find anything related
> > to slots. Is that default decided based on the memory size?
> > Thanks,
> > Kartheek.
> Keith Wiley [EMAIL PROTECTED] keithwiley.com
> "I do not feel obliged to believe that the same God who has endowed us with
> sense, reason, and intellect has intended us to forgo their use."
> -- Galileo Galilei