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SubjectRe: How is user space notified of CPU speed changes?
Lee Revell wrote:
> On Fri, 2004-10-22 at 13:40 -0600, Chris Friesen wrote:
>>x86 really could use an on-die register that increments at 1GHz independent of
>>clock speed and is synchronized across all CPUs in an SMP box.
>
>
> Like this? (posted to jackit-devel):
>
> On Fri, 2004-10-22 at 18:20 -0500, Jack O'Quin wrote:
>>On PowerPC, JACK uses the lower half of the 64-bit Timebase register,
>>which is accessible from user mode. This is better then the i386
>>cycle counter, I believe.

Yes, ppc tbr is nice. It's actually lower resolution than the x86 one, but it
might be better for smp and freq changes--not sure.

Chris
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