Re: [PATCH] i386: fix TSC clock source calibration error

From: Daniel Walker
Date: Thu Oct 18 2007 - 16:46:17 EST


On Tue, 2007-10-16 at 10:50 -0400, Dave Johnson wrote:
>
> range of tsc_khz # of boots % of boots
> ----------------- ---------- ----------
> < 1999750 0 0.000%
> 1999750 - 1999800 21 3.048%
> 1999800 - 1999850 166 24.128%
> 1999850 - 1999900 241 35.029%
> 1999900 - 1999950 211 30.669%
> 1999950 - 2000000 42 6.105%
> 2000000 - 2000000 0 0.000%
> 2000050 - 2000100 0 0.000%
> [...]
> 2000100 - 2015000 1 0.145% << BAD
> 2015000 - 2030000 6 0.872% << BAD
> 2030000 - 2045000 1 0.145% << BAD
> 2045000 < 0 0.000%
>
> The worst boot was 2032.577 Mhz, over 1.5% off!

Can you tell us what type of machine this was? I've seen complaints
where the SMI's can cause some other funny stuff with calibration , be
no one can every reproduce anything..

Daniel

-
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/