Thanks Greg! On Wed, Mar 2, 2011 at 5:07 PM, Greg Roelofs <roel...@yahoo-inc.com> wrote:
> > Could someone throw some light as to how intuitively fixed-type slots in > > Hadoop have a negative impact of cluster utilization as mentioned in > Arun's > > blog? > > It's pretty simple: in the course of time, a real cluster with a mix of > job types and submission times will have periods of high map-slot usage > (with reduce-slots available), and vice versa. Being able to assign > machine > resources to whatever kind of task needs them at any given time means > you're > not wasting those resources. > > In short: map- vs. reduce-slots is an artificial and unnecessary > restriction. > > Greg >
