speed loss with proxmox compared to ESXI(Vmware)
-
I’ve been running pfSense as a VM on ESXi for a few years without issues. I’m now migrating to Proxmox(9.1) and have run into some performance concerns.
Environment:
Two servers with near-identical specs:
Primary: Runs pfSense and several VMs full-time.
Secondary: Backup/test server, powered on only when needed.ESXi setup:
pfSense VM uses a virtual NIC for LAN.
PCI passthrough for a 2.5Gbps Intel i226 NIC for WAN.
Reason for not passing through LAN NIC: limited PCI slots and I want to maximize VM-to-WAN speed (e.g., VMs → WAN can exceed 1Gbps physical LAN NIC speed).Proxmox setup:
Using a dual 2.5Gbps Realtek NIC.
When replicating the same setup (WAN passthrough + LAN via virtual NIC), I only get about 350Mbps WAN speed, compared to 900Mbps+ on ESXi.
From what I’ve read, Proxmox uses VirtIO for virtual NICs, which may be less efficient than ESXi’s VMXNET3.
If I passthrough both Realtek NICs for WAN and LAN, speeds match ESXi performance. However, this limits VMs to 1Gbps because my switch is only 1Gbps.
I plan to upgrade my WAN to 2Gbps from 1Gbps connection soon, and only care about VMs in Proxmox taking advantage of that speed—not other LAN devices.Questions:
Is this performance issue due to the Realtek NICs, or will I see the same with Intel i226 because of VirtIO?
What are the ideal settings for WAN passthrough and virtual NICs for VMs in Proxmox?
Are there recommended VirtIO tuning options for pfSense?
I’ve noticed that allocating more resources (vCPUs, RAM) to the pfSense VM improves WAN speed but that is not something i can really afford to do as the primary server is at its limits with the VMs and resources it has. Is there best practices here currently Pfsense has 1vCPU and 2GB RAM allocated to the VM and i never needed more with ESXI.Any advice or tuning tips would be greatly appreciated!
-
The issue seems to be the network adapter for LAN was set at e1000.
No matter what i tired if i selected Virtio as NIC type it would not be recognized by Pfsense.
I seen others saying they have Virtio working with Pfsense so decided to setup a new Pfsense VM to see if that would detect the Virtio NIC and it did and all worked as expected after that.
Root cause was something wrong with the proxmox VM and creating a new Pfsense VM resolved it.
-
@swansense You might have been able to just remove the e1000 nic from hardware and then add it back in as virtio without having to recreate the vm. I run pfS on proxmox and i dont bother with nic passthrough. I have a 1Gbps link and I can saturate it no problems. I give my vm 2 cpus and 2gb, all running on an AMD Ryzen 9 Pro 6950H with a few other LXCs (smokeping, pihole).
