nelson.lamei...@lyra-network.com writes: > Hello, > > We are currently running oVirt 4.3.10 > Our oVirt hypervisors (HV) have 2 cpu sockets * 6 cores * HT = 24 vcpu > Our VMs (centos7) range globally from 2vcpu to 8vcpu > oVirt allows to configure - per VM - the following 3 advanced > parameters : virtual_sockets : cores_per_virtual_socket : > threads_per_core > > We make sure that threads per core is always 1 (so no question there) > But, for the other 2 parameters, we are unsure of the correct > configuration, and if there is a performance penalty on bad > configuration. > > Let's consider a 4vcpu VM > > 1- Is there a performance difference betwenn 1:4:1 and 4:1:1 configuration ? > 2- When should we opt for one or another configuration ? > 2- Our VMs total CPU provisionning sum is twice the hypervisors > capacity, but they are mostly idle so it is not an issue, but can this > influence configuration choice above ?
I'm not sure anybody knows an ultimate answer and/or a simple rule of thumb. My guess would be that generally there should be no significant difference. But there may be application specific considerations, especially when NUMA or something similar is involved. I think the best what can be done is to test both the configurations with your particular applications and setup and see if any of them provides a systematically better performance than the other one. Regards, Milan > Thank you for any information that can enlighthen us, since we are > worried that we are suffering from bad performance due to naive cpu > configuration choices. _______________________________________________ Users mailing list -- users@ovirt.org To unsubscribe send an email to users-le...@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/4WUNPQ5WNUVJQAHAJTH4GAJYOTTYTIMB/
