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SubjectRe: TSC to Mono-raw Drift
On Fri, 19 Oct 2018, Thomas Gleixner wrote:
> On Mon, 15 Oct 2018, Christopher Hall wrote:
> > TSC kHz used to calculate mult/shift value: 3312000
> Now the most interesting information here would be the resulting mult/shift
> value which the kernel uses. Can you please provide that?

But aside of the actual values it's pretty obvious why this happens. It's a
simple rounding error. Minimal, but still. To avoid rounding errors you'd
have to find mult and shift values which exactly result in:

(freq * mult) >> shift = 1e9

which is impossible for freq = 3312 * 1e6.

A possible fix for this is, because the error is in the low PPB range, to
adjust the error once per second or in some other sensible regular




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