Re: [libvirt] [virt-devel] RFC: Modelling timers / clocks & tick policies in libvirt

On Fri, Mar 05, 2010 at 06:50:47AM -1000, Zachary Amsden wrote: > On 03/05/2010 04:27 AM, Daniel P. Berrange wrote: > >> * HPET >> Multiple timers with periodic interrupts >> Can replace PIT/RTC timers >> >> They all generally suck in real hardware, and this gets worse in virtual >> machines. >> Many different approaches to making them suck less in VMWare, Xen& KVM, >> but there >> are some reasonably common concepts.... >> >> > HPET doesn't suck. > The VMWare timekeeping docs mentions that it has timeout race conditions, poorly defined spec for timer granularity, drift& speed of access,& bad implementations in the real world which I read as 'sucks' ;-)