Hi Joonsoo, On 04/01/2013 09:38 AM, Joonsoo Kim wrote: > Hello, Preeti. >
>> >> Ideally the children's cpu share must add upto the parent's share. >> > > I don't think so. > > We should schedule out the parent tg if 5ms is over. As we do so, we can > fairly distribute time slice to every tg within short term. If we add > the children's cpu share upto the parent's, the parent tg may have > large time slice, so it cannot be preempted easily. There may be a latency > problem if there are many tgs. In the case where the #running < sched_nr_latency, the children's sched_slices add up to the parent's. A rq with two tgs,each with 3 tasks. Each of these tasks have a sched slice of [(sysctl_sched_latency / 3) / 2] as of the present implementation. The sum of the above sched_slice of all tasks of a tg will lead to the sched_slice of its parent: sysctl_sched_latency / 2 This breaks when the nr_running on each tg > sched_nr_latency. However I don't know if this is a good thing or a bad thing. 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/
