On Tue, 2011-01-25 at 18:02 -0200, Glauber Costa wrote: > I fail to see how does clock_task influence cpu power. > If we also have to touch clock_task for better accounting of other > stuff, it is a separate story. > But for cpu_power, I really fail. Please enlighten me. static void update_rq_clock_task(struct rq *rq, s64 delta) { s64 irq_delta; irq_delta = irq_time_read(cpu_of(rq)) - rq->prev_irq_time; if (irq_delta > delta) irq_delta = delta; rq->prev_irq_time += irq_delta; delta -= irq_delta; rq->clock_task += delta; if (irq_delta && sched_feat(NONIRQ_POWER)) sched_rt_avg_update(rq, irq_delta); } its done through that sched_rt_avg_update() (should probably rename that), it computes a floating average of time not spend on fair tasks. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html