Recently I've migrated some VMs on ESXi to proxmox and now I'm facing on network performance issue on Windows 11 VM.
For comparison, I've used these machines for speed testing:
As you see, the Internet connection is capable of multi-gigabits ethernet, but performance in Win11 VM is quite low.
Could you find any cause of this problem?
Both Win11 and WinServer2019 VMs are migrated from ESXi and have "Red Hat VirtIO Ethernet Adapter".
The only difference between them is ... Windows 11 VM has a PCI passthrough device: GPU and USB Controller.
For comparison, I've used these machines for speed testing:
- proxmox bare-metal node
- Windows 11 VM (has network performance issue)
- Windows Server 2019 VM
| From | Destination | Method | Download Speed | Upload Speed |
| proxmox node | Ookla Speedtest (id: 48463) | Ookla speedtest CLI | 7350.48 Mbps | 6683.27 Mbps |
| Windows 11 VM | Ookla Speedtest (id: 48463) | Ookla speedtest CLI | 753.44 Mbps | 2541.27 Mbps |
| Windows Server 2019 VM | Ookla Speedtest (id: 48463) | Ookla speedtest CLI | 7037.86 Mbps | 4885.08 Mbps |
| Windows 11 VM | proxmox node | iperf3 | 1.11 Gbits/sec | 2.51 Gbits/sec |
| Windows Server 2019 VM | proxmox node | iperf3 | 7.11 Gbits/sec | 8.49 Gbits/sec |
| Windows 11 VM | Windows Server 2019 VM | iperf3 | 1.15 Gbits/sec | 1.58 Gbits/sec |
As you see, the Internet connection is capable of multi-gigabits ethernet, but performance in Win11 VM is quite low.
Could you find any cause of this problem?
Both Win11 and WinServer2019 VMs are migrated from ESXi and have "Red Hat VirtIO Ethernet Adapter".
The only difference between them is ... Windows 11 VM has a PCI passthrough device: GPU and USB Controller.