On Tue, Jul 30, 2013 at 05:12:49PM +0800, Ethan Zhao wrote: > On Mon, Jul 29, 2013 at 6:18 PM, Thomas Gleixner <t...@linutronix.de> wrote: > > The test case does not involve anything hrtimer related. Do you have > > CONFIG_SCHED_HRTICK enabled? > > > > Yes. it is default configured in stable release. > CONFIG_SCHED_HRTICK=y
Should still be disabled by default even if supported: # grep HRTICK kernel/sched/features.h SCHED_FEAT(HRTICK, false) > > First of all we want to know, which particular hrtimer is causing that > > issue. If it is the hrtick one, then I really have to ask why you want > > to use it at all in such a high performance scenario. > > > > Any advice about the HZ in high performance scenario ? hrtimer tick > Is not fit for high performance ? Hence why its disabled, programming the timer hardware is too expensive. But since you didn't even know that I suspect you aren't in fact using it. It would be good if you could do what Thomas suggested and look at which timer is actually active during your workload. -- 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/
