On Tue, Mar 27, 2012 at 15:07:44 -0500, Doug Goldstein wrote: > My XML configs for my VM machines have it set to AMD Opteron G3s, but > libvirt is creating QEMU with a core2duo. This is not correct at all. > I've included the setup and config of one machine that does this. But > another machine that does this matches danpb's AMD Quad Core Dual NUMA > system he posted on the mailing list recently. That machine is using a > stock qemu-0.15.1 from upstream's git and libvirt git a few commits > shy of the 0.9.11 rc1. The machine below is using libvirt 0.9.10 and > qemu-kvm-1.0. This is something we are currently working on with qemu community. The problem is that libvirt starts qemu in a way (-nodefconfig) that prevents it from reading the file that defines all modern CPU models. Try qemu -cpu ? vs. qemu -nodefconfig -cpu ? and you will see that quite a few CPU models just disappear. And since the new models (Opteron_G3 in your case) is not known to qemu when run by libvirt, libvirt transforms it into a model that qemu knows, i.e., core2duo and a bunch of additional features. So the guest will actually see a CPU that supports all features which Opteron_G3 supports. More about this issue can be found in a huge thread "Modern CPU models cannot be used with libvirt" which started in December but most of it has been discussed in March, starting with https://www.redhat.com/archives/libvir-list/2012-March/msg00416.html Jirka -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list