Re: [PATCH] Fix TSC calibration issues

From: Arjan van de Ven
Date: Wed Sep 03 2008 - 23:18:50 EST


On Wed, 3 Sep 2008 19:56:10 -0700 (PDT)
Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:

>
>
> On Wed, 3 Sep 2008, Alok Kataria wrote:
> >
> > As Linus suggested, we should be moving the tsc_read_refs outside
> > of the loop, this gives us more accurate TSC calibration when
> > calibrating against hpet/pmtimer, since we are now calibrating over
> > a period of 250ms.
>
> Side note: I'd like to change that.
>
> 250ms is a _loong_ time. It's a really really long time. It's
> human-noticeable. A quarter of a second at boot is just too long.

yeah it's insane ;-(
(since we boot a kernel in 1 second and a full OS including the kernel
in 5)

> - do other things while calibrating.

one option for that is the fastboot patchkit in -next ;-)

but at some point, even doing things in parallel/asynchronous isn't
helping, "parallel shit is still shit" :)


--
If you want to reach me at my work email, use arjan@xxxxxxxxxxxxxxx
For development, discussion and tips for power savings,
visit http://www.lesswatts.org
--
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/