lkml.org 
[lkml]   [2007]   [Aug]   [1]   [last100]   RSS Feed
Views: [more markup]  [less markup]  [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: CFS review
FromMike Galbraith <>
DateWed, 01 Aug 2007 09:36:02 +0200
On Wed, 2007-08-01 at 09:30 +0200, Ingo Molnar wrote:
> * Mike Galbraith <efault@gmx.de> wrote:

> > I haven't been able to reproduce this with any combination of 
> > features, and massive_intr tweaked to his work/sleep cycle.  I notice 
> > he's collecting stats though, and they look funky.  Recompiling.> > yeah, the posted numbers look most weird, but there's a complete lack of 
> any identification of test environment - so we'll need some more word 
> >from Roman. Perhaps this was run on some really old box that does not > have a high-accuracy sched_clock()? The patch below should simulate that 
> scenario on 32-bit x86.> > 	Ingo
> 
> Index: linux/arch/i386/kernel/tsc.c
> ===================================================================
> --- linux.orig/arch/i386/kernel/tsc.c
> +++ linux/arch/i386/kernel/tsc.c
> @@ -110,7 +110,7 @@ unsigned long long native_sched_clock(vo
>  	 *   very important for it to be as fast as the platform
>  	 *   can achive it. )
>  	 */
> -	if (unlikely(!tsc_enabled && !tsc_unstable))
> +//	if (unlikely(!tsc_enabled && !tsc_unstable))
>  		/* No locking but a rare wrong value is not a big deal: */
>  		return (jiffies_64 - INITIAL_JIFFIES) * (1000000000 / HZ);
> 

Ah, thanks.  I noticed that clocksource= went away.  I'll test with
stats, with and without jiffies resolution.

	-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/

\
 
 \ /
  Last update: 2007-08-01 09:39    [from the cache]
©2003-2008