Re: [PATCH] x86: Export tsc related information in sysfs

From: H. Peter Anvin
Date: Fri May 21 2010 - 23:37:40 EST

On 05/21/2010 07:03 PM, john stultz wrote:
> Yea, the relative instability of the tsc calibration at boot is an
> issue for folks who want very very precise timekeeping immediately
> after a reboot.
> I proposed a solution to this awhile back via a boot option users
> could use to specify the tsc_khz freq, so it would be consistent from
> boot to boot. See:
> It didn't really go anywhere due to a lack of public interest.
> However, if you're interested in playing with it, I can try to revive
> the patch.

The point about NTP is a very good one; with NTP you *really* want what
you're adjusting to be directly related to the crystal oscillator -- as
what it is; precision over accuracy as NTP takes care of accuracy but
not precision.


H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.

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