On Sat, 28 Jan 2017 12:58:41 +0100 Thomas Lindroth <thomas.lindr...@gmail.com> wrote:
> On 01/27/2017 04:52 PM, Alex Williamson wrote: > > vcpupin actually looks a little off though, just like on the host, the > > VM is going to enumerate cores then threads > > Are you sure about that? Perhaps there is some numa trick I don't > understand but it looks like the guest is a regular 6 cores > with HT (<topology sockets='1' cores='6' threads='2'/>) and > for me setups like that results in a layouts like this in the > guest (qemu-2.8.0): > > cat /proc/cpuinfo |grep "core id" > core id : 0 > core id : 0 > core id : 1 > core id : 1 > core id : 2 > core id : 2 > > The ordering in the guest is threads then cores but for the > host it's the other way around > > cat /proc/cpuinfo |grep "core id" > core id : 0 > core id : 1 > core id : 2 > core id : 3 > core id : 0 > core id : 1 > core id : 2 > core id : 3 > > Cores then threads. So to get a 1:1 match I have to use > pinning like this which is similar to that numa setup. > > <vcpupin vcpu='0' cpuset='1'/> > <vcpupin vcpu='1' cpuset='5'/> > <vcpupin vcpu='2' cpuset='2'/> > <vcpupin vcpu='3' cpuset='6'/> > <vcpupin vcpu='4' cpuset='3'/> > <vcpupin vcpu='5' cpuset='7'/> > <topology sockets='1' cores='3' threads='2'/> Oh wow, maybe I'm completely off. I hadn't noticed the core-id ordering in the VM, but indeed on my system the guest shows: core id : 0 core id : 0 core id : 1 core id : 1 core id : 2 core id : 2 core id : 3 core id : 3 Any physical system I've seen has the ordering you show above, enumerating cores then threads. Sorry Jan, maybe the way you had it originally was optimal. Thanks, Alex _______________________________________________ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
