virtualbox.org

In Virtualbox 4.3.# the hyperthread settings of the host is ignored, and one can only provision a guest's processors with up to the real number of cores. (Of course, leaving one for the host.)
My host is a Windows 7 64-bit Core-I7, 4 real cores and hyperthreading, for 8 "processors" presented to the host OS. I can run 3 "2-processor" XP guests all at the same time on this host with no problems. All guests and the host remain responsive. I have to run 2 processors in each guest, because sometimes I run intensive single-processor programs in each guest, and I've noticed the user inteface of the guest get slow and stiff when running the intensive program with just one processor in the guest.
If I update my Virtualbox from 4.2.16 to the latest 4.3, will I have to reduce my guests to one processor each to still be able to run all 3 guests at the same time? 3 processors set for the guests and one for the host? Or could I still run the guests as 2-processors each like I am now?

AFAIK no CPU logic changed in 4.3. There is no reason you have to change anything. You can still run your 3x2vCPU VMs.

Thanks, Noteirak! I'll keep this in mind when I come to upgrade time.