On Thursday 11 March 2010 16:31:57 Gleb Natapov wrote: > On Thu, Mar 11, 2010 at 10:28:12AM +0200, Avi Kivity wrote: > > On 03/11/2010 10:23 AM, Sheng Yang wrote: > > >>>I have kept --no-hpet in my setup for > > >>>months... > > >> > > >>Any details about the problems? HPET is important to some guests. > > > > > >Seems like HPET reaction is too slow to satisfy some guests(for it would > > >replace PIT). > > > > > >Here is the thread last time. > > > > > >http://thread.gmane.org/gmane.comp.emulators.kvm.devel/44899 > > > > Thanks. We can address this in three ways: first, adjust the guest > > not to do timing related tests when virtualized (since no matter > > what we do, the tests may fail). Second, I think we should > > implement userspace ack notifiers (similar to tpr access notifiers > > already present). Third, we can implement a kernel hpet, which, > > after we solve the zillion bug it introduces, will also give a nice > > performance improvement for hpet intensive workloads. > > Second will not solve the problem. Presence of ack notifiers will not > make HPET interrupt arrive faster. The slow may also due to lost tick. And with the lost tick, hpet is still unusable... -- regards Yang, Sheng -- 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
