Extremely Slow Performance with Chelsio NICs on Hyper-V (Only Pfsense Impacted)
I have a multi-node Hyper-V cluster, each with an Intel X540 10G NIC and a Chelsio T540-BT 10G NIC. The Intel NICs are in their own VM Switch and the Chelsio NICs are in a separate VM Switch.
The performance of pfSense when attached to the VM Switch using the Chelsio NICs - as measured with iperf and real-world usage - is horrible (approximately 50Kbps). Switching the same pfSense instances to the VM Switch using Intel results in 6+Gbps of throughput.
To rule out the Chelsio NICs themselves, I ran multiple tests. Both Windows virtual machines and non-pfSense FreeBSD 11.2 VMs can push 6+Gbps without an issue on the same vSwitch where pfSense instances are getting under 1Mbps. This has been replicated across several pfSense instances, including a fresh install of 2.4.4-p2.
I have played with VMQ on/off, SR-IOV on/off, and the pfSense offload options (every variation of the three checkboxes) without any improvement. Given that FreeBSD 11.2 seems to work perfectly on the exact same setup, it seems like this may be a bug in pfSense.