As long as you keep inside the NUMA limits you should be OK.For example:1 core , 2 threads is equal to 2 cores, 1 thread eachAfter all, all VMs in KVM are just processes. Yet, if your server has 2 CPUs each with 6 cores ( 2 threads per core ) ,you should avoid setting VMs with 13 vCPUs (13 real threads) as you will have to use some of the threads on the second CPU. i think there is a guide for High Performance VMs where NUMA cases are described quite well. Best Regards,Strahil Nikolov On Mon, Mar 7, 2022 at 16:37, Laurent Duparchy<duparchy@esrf.fr> wrote: Thanks for your reply. So, no performance issue if the virtual topology does not match the physical one ? Laurent Duparchy ESRF - The European Synchrotron MIS Group 04 76 88 22 56 Strahil Nikolov wrote on 07/03/2022 15:10: I think it's most useful for licensing purposes -> like the Win10 example Best Regards, Strahil Nikolov Hi, Given the fact that there is the option to match de CPUs physical topology (Socket / Core / Threads) , I guess it can make a difference. When ? Linux vs Windows ? (One example I know is that Windows 10 won't access more than 4 sockets.) _______________________________________________ Users mailing list -- users@ovirt.org To unsubscribe send an email to users-leave@ovirt.org Privacy Statement: https://www.ovirt.org/privacy-policy.html oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ List Archives: https://lists.ovirt.org/archives/list/users@ovirt.org/message/5BN4OWEHKAYDNL...