CPU Hotplug with Windows Server

[Lioh]

According to https://pve.proxmox.com/wiki/Hotplug_(qemu_disk,nic,cpu,memory) CPU hotplug should work out of the box on current Windows Systems. We have a Windows Server 2019 installation with VirtIO drivers installed within the VM. When I add CPU cores, those are listed in orange until the next boot and the changes are not picked up automatically within the running VM Processor Type is kvm64. Am I missing something?

Greetings

Lioh

 

[oguz]

hi,

after you've enabled cpu hotplugging, you can adjust the number of vCPUs (VM -> Hardware -> Processors -> click "Advanced")

 

[Lioh]

Thanks. Does it require NUMA to be enabled in order to work?

 

[oguz]

yes, can be enabled in the same window as before

make sure your system has the required udev rule mentioned in the wiki page you sent

 

[Lioh]

Hi again.

we have configured it accordingly and Qemu Guest Agents are running inside the VM (Note: it's a Windows Server 2019 VM, not Linux).


I have then increased the number of vCPUs while the VM is running but the change is not reflected within the Windows VM (still sees the old number). Am I missing somehting?

Greetings
Lioh