VM extremely slow with AMD Ryzen 1st series

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Hello,

I use KVM with SPICE on Fedora 37 (virt-manager as GUI), at least for the first installation, then the intention is to use xrdp.
The problem is that the VM is extremely slow, it’s several hours only for the installation and basic configuration, every time I click someone it responds after 10-20 seconds.

My hardware is AMD 1600 and AMD GPU 5700XT (even though it shouldn’t be a part of this issue).
My SSD is fast enough, it’s not a problem, for example, the image validation during the boot is fast, but then the slowness starts, right after that step.

I’m really not sure what CPU type I should select, I think I tried all of them at this point, but I don’t see the Ryzen series listed there.
Note that CPU passthrough is not supported.

Shall I switch to Intel to avoid these issues?
What system would allow me to use Fedora without any obvious compatibility issues? I need to run several VMs and I’m quite stuck…

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I use libvirt and virt-manager (QEMU/KVM & VMM) regularly and have never seen what you show.

I use an AMD 5 3600 with nvidia GTX 1050 Ti.

When I build the VM I normally assign 2 CPU, 8 GB ram, and ~50 GB disk space. Installation is done from an ISO I downloaded to the host system and is on the local drive.
Generally, as soon as I tell VMM what ISO is being used for installation the system picks the os to install, – i.e. when I select the fedora 37 iso it shows it is installing fedora 37 immediately.

I never see an option to select the CPU or type, only the number of CPUs to assign.
The user does not assign a CPU type, merely one from the host.

No, you cannot do CPU passthru since qemu manages the cpu and the ram usage. It is possible to do GPU passthru, but only if you have a GPU that can be dedicated to the VM since they are not shared when done in that way.

It is possible to create a VM with a different architecture, such as running an ARM VM on an x86 host, though I think most use VMs of the same arch as the host.

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Oh yeah, that sounds like you have to enable AMD-V (AMD Virtualization) in the UEFI (BIOS) of your PC.
Do you know how to enter the UEFI settings? If yes, search for the AMD-V option and enable it. Most of the time it is somewhere under “security”.

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Check the output:

sudo virt-host-validate; gnome-boxes --checks
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During the installation yes, it picks up some CPU type automatically, but for me it happens exactly that even when I change the CPU type…

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Thanks, it’s enabled, but I’ll check again…

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QEMU: Checking for hardware virtualization : PASS
QEMU: Checking if device /dev/kvm exists : FAIL (Check that the ‘kvm-intel’ or ‘kvm-amd’ modules are loaded & the BIOS has enabled virtualization)
QEMU: Checking if device /dev/vhost-net exists : PASS
QEMU: Checking if device /dev/net/tun exists : PASS
QEMU: Checking for cgroup ‘cpu’ controller support : PASS
QEMU: Checking for cgroup ‘cpuacct’ controller support : PASS
QEMU: Checking for cgroup ‘cpuset’ controller support : PASS
QEMU: Checking for cgroup ‘memory’ controller support : PASS
QEMU: Checking for cgroup ‘devices’ controller support : PASS
QEMU: Checking for cgroup ‘blkio’ controller support : PASS
QEMU: Checking for device assignment IOMMU support : PASS
QEMU: Checking if IOMMU is enabled by kernel : PASS
QEMU: Checking for secure guest support : WARN (AMD Secure Encrypted Virtualization not supported by the currently used kernel)
LXC: Checking for Linux >= 2.6.26 : PASS
LXC: Checking for namespace ipc : PASS
LXC: Checking for namespace mnt : PASS
LXC: Checking for namespace pid : PASS
LXC: Checking for namespace uts : PASS
LXC: Checking for namespace net : PASS
LXC: Checking for namespace user : PASS
LXC: Checking for cgroup ‘cpu’ controller support : PASS
LXC: Checking for cgroup ‘cpuacct’ controller support : PASS
LXC: Checking for cgroup ‘cpuset’ controller support : PASS
LXC: Checking for cgroup ‘memory’ controller support : PASS
LXC: Checking for cgroup ‘devices’ controller support : PASS
LXC: Checking for cgroup ‘freezer’ controller support : FAIL (Enable ‘freezer’ in kernel Kconfig file or mount/enable cgroup controller in your system)
LXC: Checking for cgroup ‘blkio’ controller support : PASS
LXC: Checking if device /sys/fs/fuse/connections exists : PASS
• The CPU is capable of virtualization: yes
• The KVM module is loaded: no
• Libvirt KVM guest available: no
• Boxes storage pool available: no
Could not get “gnome-boxes” storage pool information from libvirt. Make sure “virsh -c qemu:///session pool-dumpxml gnome-boxes” is working.
• The SELinux context is default: yes

Report bugs to http://gitlab.gnome.org/gnome/gnome-boxes/issues.
Boxes home page: https://wiki.gnome.org/Apps/Boxes.

lsmod | grep -i kvm
kvm 1318912 0
irqbypass 16384 1 kvm

I’ll check again the UEFI config…

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ok, I had AMD SVN (virtualization option) disabled for some reason in the UEFI…
I think the UEFI upgrade screwed it.

But these things were also responsable for it, mainly the Hypervisor choice I guess.

Overview

  • Hypervisor → KVM (for some reason I had QEMU TGC)
    You need to edit the xml in this way:
    domain type=“kvm”

  • Chipset Q35 (no issues here, but double check)

  • Firmware (make sure it’s BIOS instead of UEFI)
    In Windows 11, only UEFI should work, this is the most complete guide I found but I didn’t test it yet.
    Windows 11 on Fedora: Windows 11 on KVM – How to Install Step by Step? – GetLabsDone

CPUs → Configuration

Trigger the option “Copy host CPU configuration”

Display Spice → Address: Localhost is the default one

(for some reason I had Hypervisor default)

Bottom line, leave the default config as much as possible and make sure that the virtualization option is enabled in the UEFI, which I though it was…

The start may be a bit slower than expected with the dracut script, but after that, all goes fast.

Thanks everyone!!!