Using Mellenox ConnectX-3 NICs (driver: mlx4en) traffic reporting is still broken. Oddly enough, this only affects setups in which VLANs are defined on virtual functions (i.e. VFs, see https://docs.google.com/spreadsheets/d/1RVj8K3XOzWi-Bkjq6hUxWudu7Cxd8FFTqjLiBMzZWEM/edit#gid=0 (https://docs.google.com/spreadsheets/d/1RVj8K3XOzWi-Bkjq6hUxWudu7Cxd8FFTqjLiBMzZWEM/edit#gid=0)). Thus netmap generally works, just not in this instance. When VLANs are assigned in OPNSense (which has it's drawbacks compared to VFs), it works as intended. It would be great if anyone could have a look at this :)
https://github.com/opnsense/src/issues/103 (https://github.com/opnsense/src/issues/103)
https://github.com/opnsense/src/issues/103#issuecomment-903162524