Re: [PATCH] i386 No-Idle-Hz aka Dynamic-Ticks 3

Con Kolivas
2005-08-05T00:35:44Z

On Fri, 5 Aug 2005 08:12 am, Marc Ballarin wrote:
> On Wed, 3 Aug 2005 15:59:24 +1000
>
> Con Kolivas <kernel@kolivas.org> wrote:
> > This is the dynamic ticks patch for i386 as written by Tony Lindgen
> > <tony@atomide.com> and Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>.
> > Patch for 2.6.13-rc5
>
> One issue (tested the -rc4 Version on -mm):
> - on interrupt flood (ping -f) HZ goes down to 0-4 HZ.
> This matches "ticks to skip" below. Coincidence?
>
> - ping -f complains:
> .Warning: time of day goes back (-304us), taking countermeasures.
> ...
> .Warning: time of day goes back (-33us), taking countermeasures.
>
> Yet, system time _seems_ to be kept correctly.

Interesting... It almost seems like if you throw enough interrupts at it the
next_timer_interrupt function gets confused. I wonder if S390 and ARM are
seeing this at all since (it seems to me) they use that function?

Con