On Sat, May 23, 2009 at 03:43:12PM -0400, Gerry Reno wrote: > I upgraded the host from F10 to F11 (x86_64) with no issues. Now when I > start a F10 (i386) guest it runs very very slow. I also see messages on > the guest boot console about "clocksource tsc unstable" and some kernel > oops. Once it got far enough to start network I logged in and checked > the clocksource and it currently is 'acpi_pm' even though the kernel > line says clocksource=pit. The available clocksources are acpi_pm, > jiffies, and tsc. I do not see 'pit' in the list. How do I fix this issue? > If the guest runs 'extrememly' slowly then the most like thing is that it has fallen back to using QEMU emulation, instead of KVM hardware acceleration. Check the /var/log/libvirt/qemu/$GUEST.log to see if there is any mesage about not being able to open /dev/kvm. Also make sure that KVM modules are loaded, and that 'virsh capabilities' lists KVM as a valid domain. Daniel

Gerry Reno wrote: > Daniel P. Berrange wrote: >> On Sat, May 23, 2009 at 03:43:12PM -0400, Gerry Reno wrote: >> >>> I upgraded the host from F10 to F11 (x86_64) with no issues. Now when I >>> start a F10 (i386) guest it runs very very slow. I also see messages on >>> the guest boot console about "clocksource tsc unstable" and some kernel >>> oops. Once it got far enough to start network I logged in and checked >>> the clocksource and it currently is 'acpi_pm' even though the kernel >>> line says clocksource=pit. The available clocksources are acpi_pm, >>> jiffies, and tsc. I do not see 'pit' in the list. How do I fix this issue? >>> >> >> If the guest runs 'extrememly' slowly then the most like thing is that >> it has fallen back to using QEMU emulation, instead of KVM hardware >> acceleration. Check the /var/log/libvirt/qemu/$GUEST.log to see if there >> is any mesage about not being able to open /dev/kvm. Also make sure that >> KVM modules are loaded, and that 'virsh capabilities' lists KVM as a valid >> domain. >> >> Daniel >> > Ok, I checked the guest log and it says: > /dev/kvm: no such file or directory. > > So how do I make this node? Shouldn't libvirt have made it for us? > Ok, once I got both kernel modules loaded, it created the /dev/kvm device and now everything runs fine.

Gerry Reno wrote: > Gerry Reno wrote: > >> Gerry Reno wrote: >> >>> Daniel P. Berrange wrote: >>> >>>> On Sat, May 23, 2009 at 03:43:12PM -0400, Gerry Reno wrote: >>>> >>>> >>>>> I upgraded the host from F10 to F11 (x86_64) with no issues. Now when I >>>>> start a F10 (i386) guest it runs very very slow. I also see messages on >>>>> the guest boot console about "clocksource tsc unstable" and some kernel >>>>> oops. Once it got far enough to start network I logged in and checked >>>>> the clocksource and it currently is 'acpi_pm' even though the kernel >>>>> line says clocksource=pit. The available clocksources are acpi_pm, >>>>> jiffies, and tsc. I do not see 'pit' in the list. How do I fix this issue? >>>>> >>>>> >>>> If the guest runs 'extrememly' slowly then the most like thing is that >>>> it has fallen back to using QEMU emulation, instead of KVM hardware >>>> acceleration. Check the /var/log/libvirt/qemu/$GUEST.log to see if there >>>> is any mesage about not being able to open /dev/kvm. Also make sure that >>>> KVM modules are loaded, and that 'virsh capabilities' lists KVM as a valid >>>> domain. >>>> >>>> Daniel >>>> >>>> >>> Ok, I checked the guest log and it says: >>> /dev/kvm: no such file or directory. >>> >>> So how do I make this node? Shouldn't libvirt have made it for us? >>> >>> >> Ok, once I got both kernel modules loaded, it created the /dev/kvm >> device and now everything runs fine. >> >> > Well, not quite so fine. If I reboot the machine then the kvm modules > are no longer loaded. How do I keep these modules loaded? > I'm assuming that you haven't installed qemu from the F-11 packages. If you install the qemu-system-x86 on F-11, it comes with a file /etc/sysconfig/modules/kvm.modules. On bootup, any scripts in that directory are executed, and that command automatically loads the appropriate modules for you. If you don't want to install the F-11 qemu-system-x86 package for some reason, you'll have to arrange to do the same with a custom script in that directory, or just in /etc/rc.d/rc.local.