[SOLVED] Question about performance of VMs

[rogierl]

I have a question about the performance of my Ubuntu 22.04 VMs, running on my home server. In Proxmox 8, the default CPU is "×86-64-v2-AES'. When I keep using this setting, then the performance is really bad. However when I change the setting to "Default (kvm64)", then everything works really smooth. Now my question is: why is that? What is missing/wrong with my host system that is causing this?

The server runs on an ASRock B85M Pro4 mainboard with a Intel Pentium G3240 processor. I know it's old hardware and I want to replace it, but I'm still wondering what the best hardware is for my usecase.

 

[_gabriel]

it seems Pentium G3240 missing AES support, so iirc "x86-64-v2-AES" is emulated, you can choose "host" to get all features host cpu and best performance.

 

[rogierl]

it seems Pentium G3240 missing AES support, so iirc "x86-64-v2-AES" is emulated, you can choose "host" to get all features host cpu and best performance.

Thanks! I wonder why proxmox doesn't set the default value for this option based on the host CPU.

 

[_gabriel]

Thanks! I wonder why proxmox doesn't set the default value for this option based on the host CPU.

because can break Live migration between differents hosts cpu
btw, cpu without AES is uncommon

 

[rogierl]

Clear answer. Indeed for portability reasons I understand this.

Thanks again .