On Wed, Jan 08, 2014 at 12:35:34PM +0000, Morten Rasmussen wrote:
Currently we detect overload by sg.nr_running >= sg.capacity, which can be very misleading because while a cpu might have a task running 'now' it might be 99% idle.
At which point I argued we should change the capacity thing anyhow. Ever since the runnable_avg patch set I've been arguing to change that into an actual utilization test.
So I think that if we measure overload by something like >95% utilization on the entire group the load scaling again makes perfect sense.
I agree that it make more sense to change the overload test to be based on some tracked load. How about the non-overloaded case? Load balancing would have to be based on unweighted task loads in that case?
Yeah, until we're overloaded our goal is to minimize idle time.