[ovirt-users] Re: pass-through CPU

2023-01-23 Thread Strahil Nikolov via Users
You can check which families are supported by an oVirt Host via:virsh 
domcapabilities | xmllint --xpath '/domainCapabilities/cpu' -
For the instruction set - it all depends on the app. Set your VM with the 
cluster's top notch CPU , run your app and note down the performance 
indicators. Once the test is over, shitdown the VM, set the CPU to 
host-passthrough and test again.
Best Regards,Strahil Nikolov 
 
 
  On Mon, Jan 23, 2023 at 15:19, Laurent Duparchy wrote:   
___
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/TNLZJSGJTSCT6YSQPKC7YETRD4VAPZ3J/
  
___
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/V4WXHFHPOH5E3UMD4JXROALZHS7KRGJI/


[ovirt-users] Re: pass-through CPU

2023-01-23 Thread Laurent Duparchy

Hi,

Thanks for you reply.

As far as we are concerned, we have two clusters with perfectly identical CPUs, 
respectively. Not the same family.
I understand that a cluster will only allow CPUs of the  same "family" but I 
never  investigate that.
Is there a  CPU family <--> CPU name relationship somewhere ?

That said, are those extra instructions only relevant to nested virtualization, 
or can they provide real performances improvement ?

*Laurent Duparchy
ESRF - The European Synchrotron
MIS Unit
04 76 88 22 56*
Strahil Nikolov wrote on 18/01/2023 18:08:

If you have hosts with the exact  same cpu, you can enable cpu passthrough and set the hosts  from 
the "Specific Host(s)" section. Also you can set the migration mode to "Allow manual 
and automatic migration".

I guess you already noticed that VMs with CPU passthrough have access to more 
CPU instructions compared to the Virtualized one.

Best Regards,
Strahil Nikolov

Hi,

What are the pro and cons of enabling pass-through CPU ?

It is a greyed option for a VM, unless specific host(s) is/are selected.
That's the thing : it's possible to select all hosts..., so, it does not make 
difference w/ "Start on any host" option
___
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/H63YAWHIACRQ5K3HDCUANXUICK7NMPRY/

___
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/TNLZJSGJTSCT6YSQPKC7YETRD4VAPZ3J/


[ovirt-users] Re: pass-through CPU

2023-01-18 Thread Strahil Nikolov via Users
If you have hosts with the exact  same cpu, you can enable cpu passthrough and 
set the hosts  from the "Specific Host(s)" section. Also you can set the 
migration mode to "Allow manual and automatic migration".
I guess you already noticed that VMs with CPU passthrough have access to more 
CPU instructions compared to the Virtualized one.
Best Regards,Strahil Nikolov 
 
Hi, 

What are the pro and cons of enabling pass-through CPU ?

It is a greyed option for a VM, unless specific host(s) is/are selected. 
That's the thing : it's possible to select all hosts..., so, it does not make 
difference w/ "Start on any host" option
___
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/H63YAWHIACRQ5K3HDCUANXUICK7NMPRY/
  
___
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/V4YTI6QI7TXVOV7PYSPWGYYVDRRN3BFQ/