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SubjectRe: Use CPUID to communicate with the hypervisor.
Zachary Amsden wrote:
>> Well, that should be clearly defined, that is my point. When asking the
>> hypervisor for the tsc instead of running a calibration loop, then we
>> have a small bit of paravirtualization: The guest is aware that it runs
>> on a hypervisor and just asks it directly. So while we are at it we can
>> also define a way to communicate tsc freq changes between host and
>> guest, so the cost of trap'n'emulate tsc reads can be avoided. Or we
>> define "tsc is constant" and leave it to the hypervisor to make sure it
>>
>
> For our purposes, we define TSC is constant.
>

I believe VMware doesn't actually change cpu frequency dynamically. But
what about hypervisors that do? and what about large machines, which do
not actually have a constant tsc?

You are defining something as constant which in fact is not constant.

--
error compiling committee.c: too many arguments to function



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