virtualbox.org

I am using virtual box as a virtualization software, I have windows server 2008 as host o.s, my configuration of computer is intel core i5 2400 cpu @3.10GHZ ,8GB RAM and 640 GB hard disk .windows xp, windows vista and windows 7 are my guest o.s . I am running all of Guest o.s at the same time .i have seen in each guest o.s, the number of processor used(CPU) is 1.It is confusing me .I am worried that all three guest o.s are using just 1 cpu OR when I run one Guest o.s then 1 CPU, then two guest o.s running sametime will be 2 cpu and 3 guest o.s running same time will be 3 Processors.

pls let me know as soon as possible

thanks in advance.
Sharad Aryal @UDC

SMP requires hardware-v (VT-x/AMD-v) and the CPU and bios of your host must support and it be active.
If you installed the Windows guest with a single processor you will need to change them to multi-processor kernels.
Search for HALu.

Unless you have a specific need for the guests to see multiple cores then I would leave things as they are. Performance is unlikely to be improved by giving the guest multiple cores.

In regard to how it works right now, yes I would expect any "busy" processes on the host to run on separate cores, so that would include VMs.

I noticed my Win 7 64 slow down when I increased it to four cores. You have to toy with the config to find the optimal setting.