Hi, On 03/30/2013 07:34 PM, Alex Shi wrote: > On 03/30/2013 07:25 PM, Preeti U Murthy wrote: >>>> I still give the rq->util weight even the nr_running is 0, because some >>>> transitory tasks may actived on the cpu, but just missed on balancing >>>> point. >>>> >>>> I just wondering that forgetting rq->util when nr_running = 0 is the >>>> real root cause if your finding is just on VM and without fixed VCPU to >>>> CPU pin. >> I find the same situation on a physical machine too. On a 2 socket, 4 >> core machine as well. In fact, using trace_printks in the load balancing >> part, I could find that the reason that the load was not getting >> consolidated onto a socket was because the rq->util of a run-queue with >> no processes on it, had not decayed to 0, which is why it would consider >> the socket as overloaded and would rule out power aware balancing.All >> this was on a physical machine. > > Consider of this situation, we may stop account the rq->util when > nr_running is zero. Tasks will be a bit more compact. but anyway, that's > powersaving policy. > True, the tasks will be packed a bit more compactly, but we can expect the behaviour of your patchset *defaulting to performance policy when overloaded*, to come to the rescue of such a situation.
Regards Preeti U Murthy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
