On Tue, Aug 24, 2010 at 01:01:38PM -1000, Zachary Amsden wrote: > >>With this patchset, KVM now has a much stronger guarantee: If you have > >>old guest software running on broken hardware, using SMP virtual > >>machines, you do not get hardware performance and error-free time > >>virtualization. However, if you have new guest software, non-broken > >>hardware, or can simply run UP guests instead of SMP, you can have > >>hardware performance, and it is now error free. Alternatively, you can > >>sacrifice some accuracy and have hardware performance, even for SMP > >>guests, if you can tolerate some minor cross-CPU TSC variation. No > >>other vendor I know of can make that guarantee. > >> > >>Zach > >If the processor has a stable TSC why trap it? I realize you are trying > >to cover a gauntlet of hardware and guests, so maybe a nerd knob is > >needed to disable. > > Exactly. If you have a stable TSC, we don't trap it. If you don't > have a stable TSC, we do. That's the point of these patches. Wait, don't you trap if host TSC is faster than guest TSC? -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
