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Re: TSC vs. HPET timecounter priority
On Aug 13, 2012, at 08:49, Jukka Ruohonen wrote:
> 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.
Can you find a reference in either Intel or AMD's documentation, and to which
CPUs that applies (preferably with some indicator we can test at system
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