On Tue, Oct 01, 2013 at 11:23:07AM -0500, Ben "Root" Anderson wrote: > Fair enough in itself, but if HPET is known to have problems with > arguably the most popular OS family to use as a guest, why is it > enabled by default? > Arguably :) But QEMU defaults are arguably far from been optimal for any guest.
> On Tue, Oct 1, 2013 at 10:56 AM, Gleb Natapov <g...@redhat.com> wrote: > > On Tue, Oct 01, 2013 at 09:34:06AM -0000, Ben A wrote: > >> Apparently this bug's still alive and kicking. > >> > > And no plans to fix it. Do not use hpet with windows guests this buys > > you nothing. > > > >> There's an obvious clock skew problem on Windows 7; in the Date & Time > >> dialog, the clock jumps through seconds visibly too fast. > >> > >> I also found a case where HPET bugs are causing a real problem: Terraria > >> (dedicated server) seems to be relying on (something that relies on) > >> HPET, and QEMU doesn't get it right. The result is a goofy and > >> aggravating behavior I've nicknamed "Turbo Monsters of Doom" and it > >> makes killing anything tougher than a normal zombie basically > >> impossible. > >> > >> -- > >> You received this bug notification because you are a member of qemu- > >> devel-ml, which is subscribed to QEMU. > >> https://bugs.launchpad.net/bugs/599958 > >> > >> Title: > >> Timedrift problems with Win7: hpet missing time drift fixups > >> > >> Status in QEMU: > >> Confirmed > >> > >> Bug description: > >> We've been finding timedrift issues witth Win7 under qemu-kvm on our > >> daily testing > >> > >> kvm.qemu-kvm-git.smp2.Win7.64.timedrift.with_load FAIL 1 Time > >> drift too large after rest period: 38.63% > >> kvm.qemu-kvm-git.smp2.Win7.64.timedrift.with_reboot FAIL 1 Time > >> drift too large at iteration 1: 17.77 seconds > >> kvm.qemu-kvm-git.smp2.Win7.64.timedrift.with_migration FAIL 1 > >> Time drift too large at iteration 2: 3.08 seconds > >> > >> Steps to reproduce: > >> > >> timedrift.with_load > >> > >> 1) Log into a guest. > >> 2) Take a time reading from the guest and host. > >> 3) Run load on the guest and host. > >> 4) Take a second time reading. > >> 5) Stop the load and rest for a while. > >> 6) Take a third time reading. > >> 7) If the drift immediately after load is higher than a user- > >> specified value (in %), fail. > >> If the drift after the rest period is higher than a user-specified > >> value, > >> fail. > >> > >> timedrift.with_migration > >> > >> 1) Log into a guest. > >> 2) Take a time reading from the guest and host. > >> 3) Migrate the guest. > >> 4) Take a second time reading. > >> 5) If the drift (in seconds) is higher than a user specified value, fail. > >> > >> timedrift.with_reboot > >> > >> 1) Log into a guest. > >> 2) Take a time reading from the guest and host. > >> 3) Reboot the guest. > >> 4) Take a second time reading. > >> 5) If the drift (in seconds) is higher than a user specified value, fail. > >> > >> This bug is to register those issues and keep an eye on them. > >> > >> Attached, some logs from the autotest tests executed on the guest > >> > >> To manage notifications about this bug go to: > >> https://bugs.launchpad.net/qemu/+bug/599958/+subscriptions > > > > -- > > Gleb. -- Gleb.