Nested virtualization very slow: Intel vs AMD thoughts

[decibel83]

Hi.
For the purpose of creating a testing and development environment I need a virtual machine which hosts a Virtualbox installation.
For this reason I enabled the nested virtualization following instructions at https://pve.proxmox.com/wiki/Nested_Virtualization on two different physical hosts:

• AMD Ryzen 9 5950X 16-Core Processor, 32 vCore (Hetzner AX101), CPU mark 46.175
• Intel(R) Xeon(R) CPU E5-2650L v2 @ 1.70GHz, 40 vCore (HP Proliant DL380p Gen8), CPU mark 7.475

I installed a Debian Bullseye virtual machine, enabled the nested virtualization and installed Virtualbox in it.

Well, Virtualbox's virtual machines on the AMD Ryzen host is pretty usable (not super-fast, obviously but they are usable without critical problems), but on the E5-2650L host Virtualbox is simply hanged and unusable: Windows 10 installation takes hours, and after it is simply unusable.

I completely know that the E5-2650L CPU is pretty old and not so fast, but I was not thinking about this such slowness, so I have a couple of questions:

• is this behaviour normal and expected, because the E5-2650L is slow and old?
• is AMD really better than Intel processors for nested virtualization purposes?
• would a newer Intel CPU (like i9, for example) be faster than the Ryzen?

I am making these questions because I am thinking about buying or assembling a new host expecially for nested virtualization purposes, so I need to choose between Intel i9 and AMD Ryzen 9 processor.

Thank you very much!

 

[MarkusF]

Hello.

• is this behaviour normal and expected, because the E5-2650L is slow and old?

Yes. Also Virtualbox is not the most efficient way of virtualization and windows is not really resource-saving.

• is AMD really better than Intel processors for nested virtualization purposes?

This shouldn't make a great difference except for the fact that most amd cpus have more cores for a cheaper price than intel.

Notice: Windows 10 with WSL2 and Windows 11 with WSL either does not work on AMD or has a bad performance. Kernel 5.15 should have made the support a bit better.

• would a newer Intel CPU (like i9, for example) be faster than the Ryzen?

maybe, probably also more expensive than a ryzen. compare them.