On 11/10/2010 07:59 PM, compdoc wrote: > I can't say if KVM will see 6 or 12 cores as I don't run the same hardware. > It's easy enough to install centos and find out. > > When you create a virtual machine in KVM, you assign virtual cpus to the > guest - from 1, to as many as you think the guest will need. > > For performance reasons, I personally think it's better to keep the total > number of virtual cpus in all of your guests close to the number of real > cpus. But since most computers are idle 99% of the time, you have a lot of > room for experiment... Interesting. I only have two cores and no virtualization on this machine Four cores works (2 more than I actually have) # qemu-kvm -smp 4 -m 768 -k en-us -net nic,vlan=0.5 VB-ReactOS.img But 5 and 6 whines # qemu-kvm -smp 5 -m 768 -k en-us -net nic,vlan=0.5 VB-ReactOS.img kvm_create_vcpu: Invalid argument Segmentation fault So, I can not tell. My big concern here is that if I tell it 4 cores on my customer's x5650 (6 hardware cores), I will actually get 4 hyperthreaded cores for a total of 2 actual cores. My experience with Virtual Box tells me to save some cores for the host. Here is a heads up: if running a Windows guest, make sure you only use an even number of cores. M$ freaks out at an odd number of cores, especially m$sql server. -T