HDD queue settings for VM

showiproute

Active Member
Mar 11, 2020
579
29
33
35
Austria
Hello there,

can someone tell me the "secret" where to place queue settings for a Windows VM.
Someone from Proxmox staff told me some years ago to add this to the guest config itself - but I am unable to find this thread and also Google is not showing something useful.

Background is that I am currently playing around with different zvol blocksizes to determine which one would be the best for a sequential storage VM disk.
But currently I am already having issues with throughput.

Copy paste native to the ZFS PVE system -> 1 GB/s
Copy past to WIndows VM -> 100 MB/s
 
Last edited:
While doing my tests I stumbled accross a very weird behaviour:
My Win22k server used IPv4 & IPv6 with dedicated addresses.
Current settings:

Code:
agent: 1
bios: ovmf
boot: order=scsi0;ide2
cores: 8
cpu: host
efidisk0: local-lvm:vm-109-disk-0,efitype=4m,pre-enrolled-keys=1,size=4M
ide2: none,media=cdrom
machine: pc-q35-8.0
memory: 16384
name: WindowsServer
net0: virtio=3E:0E:15:D6:44:5A,bridge=vmbr0,queues=8,tag=10
numa: 1
onboot: 1
ostype: win11
parent: autohourly231024090523
scsi0: local-lvm:vm-109-disk-1,discard=on,size=200G,ssd=1
scsi1: Data:vm-109-disk-3,discard=on,size=2T
scsi2: Media:vm-109-disk-2,backup=0,discard=on,size=10T
scsi3: Data:vm-109-disk-0,backup=0,discard=on,size=3T
scsi4: Data:vm-109-disk-1,discard=on,size=4T
scsi5: Media:vm-109-disk-1,backup=0,discard=on,size=11T
scsi6: Data:vm-109-disk-2,backup=0,discard=on,size=500G
scsi7: Media:vm-109-disk-3,backup=0,cache=unsafe,discard=on,size=100G
scsihw: virtio-scsi-pci
smbios1: uuid=4e7d194d-448c-4585-b349-766632e7df21
sockets: 2
tablet: 0
vga: qxl
vmgenid: e37435c3-09c6-4069-aefa-bc2328418d91
vmstatestorage: local-lvm


comment: scsi7 is the drive where I try to play around with different zvol blocksizes.



Anyway if IPv4 && v6 are enabled I only get a througput of a 1 Gbit connection (~ 120 Mb/s) independently if I copy stuff over to a NVMe SSD or regular spinner HDD.

As soon as I disable IPv6 within Windows network settings the network throughput gets a lot better (~ 600 Mb/s).


Is this a known bug?
 

About

The Proxmox community has been around for many years and offers help and support for Proxmox VE, Proxmox Backup Server, and Proxmox Mail Gateway.
We think our community is one of the best thanks to people like you!

Get your subscription!

The Proxmox team works very hard to make sure you are running the best software and getting stable updates and security enhancements, as well as quick enterprise support. Tens of thousands of happy customers have a Proxmox subscription. Get yours easily in our online shop.

Buy now!