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Re: TSC vs. HPET timecounter priority

On Sun, Aug 12, 2012 at 08:14:50PM -0700, Erik Fair wrote:
> NetBSD has a problem with NTP time keeping on x86 systems which have TSC:
> if those systems have variable CPU clock frequency support for power
> consumption efficiency (e.g.  SpeedStep, PowerNow), if or when the CPU
> frequency changes, the relationship between TSC and the ticking of real
> time changes.  That screws up any kind of interval time & frequency
> measurement one is using TSC for.

I think this is no longer true with new AMD and Intel processors.

- Jukka.

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