Re: Large increase in context switch rate

From: Andi Kleen
Date: Thu Jul 17 2008 - 17:43:38 EST


Jeremy Fitzhardinge <jeremy@xxxxxxxx> writes:
>
> OK, but that still doesn't account for the relatively large increase
> from 2.6.18 -> 2.6.26. You're using HZ=100 in both cases, I presume.
>
> The other variable is NOHZ and highres timers. You could try turning
> those off in 2.6.26. Also, CONFIG_PREEMPT could well make a
> difference. 2.6.18-xen doesn't support CONFIG_PREEMPT at all, but
> pvops(-xen) does.

If it's that easily reproducible you could just bisect it?

-Andi
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/