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Subject: Re: TSC Timecounter and multi-core/SMP
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David O'Brien wrote:

> 
> The TSC on K8 is not invariant - its rate of change is affected by
> P-state changes.
> 
> The TSC on Greyhound (Family 10h) is invariant.
> [but as stated above, is not synced with other cores]

You'd think that an invariant sync'd clock (fast to read) of some
type would have been done by someone by now.. The software people
have been asking for this for the last decade at least.

>