PVE windows virtual machine external network download bandwidth + intranet SMB transmission bandwidth is far less than the Gigabit speed


New Member
Mar 16, 2021
Sorry about this problem. It is solved now. My switch is out of order and I am buying a new one.


1. There are windows server 2019 on PVE, and I also have a laptopwith windows LTSC 2019 system.

2. Whenever the CPU and hard disk are not fully loaded, the PVE machine has enough resources.

3. No matter when, the qbittorrent download speed on PVE windows can always reach 300mbps ( test with ubuntu iso torrent ).

4. When qbittorrent is not working ( not transfering data ), my laptop connected to PVE Windows can basically fill Gigabit intranet SMB ( average speed is about 85 m/s ).

5. When qbittorrent is working ( transfering data ), whether the load of qbittorrent is up to full or just a little, the intranet SMB can only run within 10m / s when my laptop send files to PVE windows.

Later, I replaced qbittorrent with IDM on PVE windows, and downloaded ubuntu iso file for testing. The performance is exactly the same as that of qbittorrent.

windows driver: virtio-win-0.1.185

Kernel Version: Linux 5.4.106-1-pve #1 SMP PVE 5.4.106-1 (Fri, 19 Mar 2021 11:08:47 +0100)

PVE Manager Version: pve-manager/6.4-4/337d6701

what I see: qbittorrent download speed + SMB share speed < 1Gbps

what I hope: qbittorrent download speed + SMB share speed = 1Gbps

What's wrong with my configuration? Or my hardware is too weak?

what can I do?

Thanks a lot.

below is my settings:

The problem is solved. My switch is out of order.
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