Messages in this thread | | | Date | Wed, 22 Jul 2009 16:38:18 +0200 (CEST) | From | Thomas Gleixner <> | Subject | Re: [RFC][PATCH] cache __next_timer_interrupt result |
| |
On Tue, 21 Jul 2009, Martin Schwidefsky wrote:
> From: Martin Schwidefsky <schwidefsky@de.ibm.com> > > Each time a cpu goes to sleep on a NOHZ=y system the timer wheel is > searched for the next timer interrupt. It can take quite a few cycles > to find the next pending timer. This patch adds a field to tvec_base > that caches the result of __next_timer_interrupt. The hit ratio is > around 80% on my thinkpad under normal use, on a server I've seen
Nice, I like it.
> hit ratios from 5% to 95% dependent on the workload.
Which workloads result in lower hit ratios ? Heavy networking ?
Thanks,
tglx
| |