Windows 11 Virtual Machine very slow performance

[guil_gp]

Hi,
I try to create some Windows 11 virtual machine but they are very slow.

I try with multi conf to have the better performance but i haven't solved the issue.

Proxmox server version : 7.3-4
Server hard drive: SSD

My virtual machine :
Hardware :
Memory : 4go
CPU : 2 socket & 2 cores
BIOS : OVMF (UEFI)
Display : default
machine : pc-q35-7.1
SCSI Controller : Virtio SCSI Single
Hard disk : sata - no cache - SSD Emulation - Async IO Default
Network : Intel e1000

Do you have any idea?

 

[guil_gp]

Hi,
Some people had a windows vm work fine ? can i have the hardware and options ?

Thanks

 

[wigor]

When it comes to performance, consider using virtio.

At first you should choose Hard-disk SCSI an not SATA. Network also: choose virtio instead of e1000.

 

[toomanylogins]

Have you installed the guest tools to use virtio ?

 

[Dunuin]

The Wiki is missing a Win11 Best Practices but you can follow the one for Win10 which should work too:
https://pve.proxmox.com/wiki/Windows_10_guest_best_practices

 

[Matthias.]

Please share the output of qm config VMID, so we can see the exact configuration.
How do you notice the slowness?

 

[guil_gp]

Hi,

Thanks, this is my conf :

agent: 1
bios: ovmf
boot: order=sata0;ide2;net0;ide0
cores: 4
efidisk0: vmdata:vm-805-disk-0,efitype=4m,pre-enrolled-keys=1,size=1M
hotplug: disk,network,usb,cpu
ide0: local:iso/Virtio-win-driver.iso,media=cdrom,size=522284K
ide2: none,media=cdrom
machine: pc-q35-7.1
memory: 4096
meta: creation-qemu=7.1.0,ctime=1675258342
name: W11
net0: virtio=B2:A4:BA:B1:4F:61,bridge=vmbr3,firewall=1
numa: 0
onboot: 1
ostype: win11
sata0: backup:805/vm-805-disk-0.qcow2,cache=writeback,size=30G
scsihw: virtio-scsi-single
smbios1: uuid=8e86cb75-e1b6-4a78-a105-e0a3fece1525
sockets: 2
tpmstate0: vmdata:vm-805-disk-1,size=4M,version=v2.0
vmgenid: 51a5566e-8e16-4ee9-97e4-94d3a215a2bf

 

[Matthias.]

Some very low hanging fruits:
set CPU type = host (the default kvm64 is incredibly slow) - note that this potentially breaks live migration
set numa: 1 if you have more than one socket on the host (why does your guest have two sockets?)
enable iothread on harddisk

https://pve.proxmox.com/wiki/Performance_Tweaks

 

[Ashes76]

I had a very bad performance with Windows 10 and 11 on virtio network. When I changed it to Intel E1000 performance became good.

 

[pille99]

i can confirm it works for windows 2022 server too
the only input - without balloning the ram was 80% (of 8gb) with balloing 12%

 

[ThinkYEAH]

Network also: choose virtio instead of e1000.

This solve my issue. Thank you!

 

[eth]

Use VirtIO-GPU (or even better, VirGL) and set display memory to 512.

 

[yyyy]

When it comes to performance, consider using virtio.

At first you should choose Hard-disk SCSI an not SATA. Network also: choose virtio instead of e1000.

This isn't the issue, I have these exact same settings yet simply trying to open a browser takes upto a minute, my many ubuntu servers are fine. Windows is unusable.

 

[raydotac]

If your windows 11 Core isolation -> Memory Integrity is enabled, the performance will be BAD in VM. Try to disable it then reboot VM.