On 02/20/2013 11:22 PM, Peter Zijlstra wrote: > On Wed, 2013-02-20 at 22:33 +0800, Alex Shi wrote: >>> You don't actually compute the rq utilization, you only compute the >>> utilization as per the fair class, so if there's significant RT >> activity >>> it'll think the cpu is under-utilized, whihc I think will result in >> the >>> wrong thing. >> >> yes. A bit complicit to resolve this. Any suggestions on this, guys? > > Shouldn't be too hard seeing as we already track cpu utilization for ! > fair usage; see rq::rt_avg and scale_rt_power. >
Hi Peter, rt_avg will be accumulated the irq time and steal time in update_rq_clock_task(), if CONFIG_IRQ_TIME_ACCOUNTING or CONFIG_IRQ_TIME_ACCOUNTING defined. That cause irq/steal time was double added into rq utilisation, since normal rq->util already include the irq time. So we do wrongly judgement to think it is a overload cpu. but it is not. To resolve this issue, if is it possible to introduce another member in rq to describe rt_avg non irq/steal beside the rt_avg? If so, what the name do you like to use? -- Thanks Alex -- 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/
