Re: [PATCH] All Transmeta CPUs have constant TSCs

[Jan Engelhardt]

On Jan 8 2007 00:02, dean gaudet wrote:
>On Fri, 5 Jan 2007, Jan Engelhardt wrote:
>> On Jan 4 2007 17:48, H. Peter Anvin wrote:
>> >
>> >[i386] All Transmeta CPUs have constant TSCs
>> >All Transmeta CPUs ever produced have constant-rate TSCs.
>> 
>> A TSC is ticking according to the CPU frequency, is not it?
>
>transmeta decided years before intel and amd that a constant rate tsc 
>(unaffected by P-state) was the only sane choice.  on transmeta cpus the 
>tsc increments at the maximum cpu frequency no matter what the P-state 
>(and no matter what longrun is doing behind the kernel's back).
>
>mind you, many people thought this was a crazy choice at the time...
>
Well it defeats the purpose of TSC. I mean, they could have kept the "TSC" and
instead added a second TSC ticker, constant_tsc.


	-`J'
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