What if you have no application and you're purely forwarding traffic? That's what I'm measuring here (and that's actually typically faster than passing packets up to user space apps to consume through syscalls).

25G line rate is 37MPPS - are you saying you have zero problem forwarding at that line rate? I'd be very surprised if that's being done in the kernel. I'd be more surprised if you said that you're consuming bytes from the network at that speed with user space apps and no kernel bypass.

XDP (the forwarding approach built on top of eBPF) is limited to ~20MPPS, as well: https://www.netronome.com/blog/bpf-ebpf-xdp-and-bpfilter-wha...