Re: [patch] sched: optimize siblings status check logic in wake_idle()

From: Siddha, Suresh B
Date: Mon Mar 05 2007 - 00:01:56 EST


On Mon, Mar 05, 2007 at 05:58:31AM +0100, Nick Piggin wrote:
> On Sun, Mar 04, 2007 at 08:13:09PM -0800, Suresh B wrote:
> > On a 16 node system, we have seen ~1.25% perf improvement on a database workload
> > when we completely short circuited wake_idle(). This patch is trying to comeup
> > with a best compromise to avoid the cache misses and also minimize the latenices,
> > perf impact.
>
> Hmm, I wonder what if we only wake_idle if the wakeup comes from this
> CPU or a sibling? That's probably going to have downsides in some
> workloads as well, though.

yep. I thought about it and thought this patch is a decent solution.

thanks,
suresh
-
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/