Ticket #9352 (new defect)
unstable clocksource when running Xen inside virtualbox
|Reported by:||sven.koehler||Owned by:|
I'm using virtualbox to test Xen 4.1.1 + Linux 3.0 dom0. By default, the Xen hypervisor tries to use the ACPI PM timer as a clocksource. It seems to be unstable and Xen complains about the timer wrapping around unexpectedly. A HPET doesn't seems to be available. The only clocksource that seems to be stable is clocksource=pit. (The dom0 kernel has clocksource=xen)
Note, that with ACPI PM timer as a clocksource, dom0 becomes and unstable and AHCI various errors pop up during HDD I/O.
This is easily reproducable here (it doesn't happen every time, but it happens very often) with VirtualBox 4.1, 64Bit Core i5 Linux host, dual core, hyperthreading. The guest is configured as OS=Other/Unknown, 4 CPUs, VT-x and Nested Paging enabled.