Messages in this thread | | | Date | Mon, 26 Dec 2005 18:15:17 +0100 | From | Mike Galbraith <> | Subject | Re: [patch 0/9] mutex subsystem, -V4 |
| |
At 03:11 AM 12/26/2005 -0800, Andrew Morton wrote: >Arjan van de Ven <arjan@infradead.org> wrote: > > > > > > > hm. 16 CPUs hitting the same semaphore at great arrival rates. The cost > > > of a short spin is much less than the cost of a sleep/wakeup. The > machine > > > was doing 100,000 - 200,000 context switches per second. > > > > interesting.. this might be a good indication that a "spin a bit first" > > mutex slowpath for some locks might be worth implementing... > >If we see a workload which is triggering such high context switch rates, >maybe. But I don't think we've seen any such for a long time.
Hmm. Is there a real workload where such a high context switch rate is necessary? Every time I've seen a high (100,000 - 200,000 is beyond absurd on my little box, but...) context switch rate, it's been because something sucked.
-Mike
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |