Re: [bisected] Clocksource tsc unstable git

Markus Trippelsdorf
2010-11-05T21:27:58Z

On Fri, Nov 05, 2010 at 05:42:25PM +0100, Markus Trippelsdorf wrote:
> On Fri, Nov 05, 2010 at 05:09:19PM +0100, Borislav Petkov wrote:
> > On Tue, Nov 02, 2010 at 11:26:54AM -0400, Thomas Gleixner wrote:
> > > Ok, I'm waiting for Boris to get us the confirmation from HW folks.
> >
> > However, we don't know (yet) whether this can be used in the
> > non-periodic mode too. My gut feeling says yes but I wouldn't trust it.
> >
> > We went and collected that value a bunch of systems and it looks like it
> > would need more massaging (read: capping) since some BIOSen simply write
> > crap in it. It ranges from
> >
> > - 0x37ee on old nVidia and Intel boards (this is definitely crap, I
> > can't imagine a minimum ticks value of 14318 for a HPET but who knows)
> >
> > - 0x1000 on a HP machine (also fishy)
> >
> > - 0x10, 0x14 on current SBxxx boards
> >
> > - 0x80 on newer Intel boards
>
> "min tick: 20" on my machine. Given that 12 is running stable here, maybe
> the value is a bit too large?

Err, 20==0x14 so it's not that much difference and it's running fine here
also.

Feel free to add:
Reported-and-tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>

Thanks.

--
Markus