virtualbox.org

When I tried a 64-bit Linux guest SMP (Suse 11.3, kernel 2.6.34-7.0.5) I experienced a lot of very strange freezes and keyboard hangs on the GUI - the mouse was working, but not the keyboard, I could resize windows, but not enter anything. In the end the GUI completely froze up and I had to reset the VM (ACPI shutdown did not work). Same behaviour on the console with the display manager and X servers killed. Very random, but somewhat correlated with I/O load: playing a movie with vlc + mp3's with Amarock + copying something big over NFS produced this strange phenomena faster (within minutes) than working with eclipse for an hour. But when I reduced the number of processors from 6 to 1, everything worked fine.

After lots of Googleing, what worked for me was switching the kernel's clocksource from TSC to jiffies (acpi_pm did *not* help): just added the clocksource=jiffies to the kernel line in the GRUB menu.

My host:
Intel Core i7 920 processor + X58 chipset, Windows 7 64-bit, Virtualbox (4.0.0)