Messages in this thread | | | Date | Thu, 23 Oct 2008 00:54:09 +0200 | From | Andi Kleen <> | Subject | Re: [PATCH] Skip tsc synchronization checks if CONSTANT_TSC bit is set. |
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> Not really, there are problems with the pm timer too, the one about > missing the counter wrap and time dropping in chunks of 4 seconds. > Tried to explain it over here, http://lkml.org/lkml/2008/10/22/525
Well then pit. Or are you saying time is always broken on VMware & Linux?
> So TSC is the ideal clocksource from performance and correctness point > of view for VMware.
But you don't seem to emulate it "ideal"ly otherwise you wouldn't need all these hacks you're adding?
I think you should either implement a TSC that matches what real hardware does (including CPUID semantics) or implement a real vmware PV timer and just say it's PV and not fully virtualized. But doesn't the vmware paravirt ops have that already anyways?
But I personally think it wouldn't really scale to add detection for more and more "nearly PV" hypervisors to the standard native kernel.
-Andi
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