Dear community,
I have a ConnectX6 Dx card installed on Ubuntu 24.04.3 LTS and would like to use XDP in native mode,with enabled zero-copy and multi-buffer support. Both options are needed to support zero copy with Jumbo Frames (MTU 9K).
Regarding that topic, i have some questions.
Different online sources mention that zero copy is supported and that Multi-Buffer mode is supported with a striding RQ.
However it looks like the combination of both, does not work. My XDP receiver (native mode) works with multiple buffers in copy mode and with single buffers in zero-copy mode. But not in multi-buffer zero-copy mode.
Querying the bpf_query_opts reports xdp_zc_max_segs=1.
- Is XDP with zero-copy and multi-buffer support available with the mlx5 driver?
- Is there any reference/documentation that states the currently supported XDP mechanisms?3) Is any special NIC configuration needed to support zero-copy in multi-buffer mode?
- Is it still true, that only certain RX Queues support zero-copy? See https://www.spinics.net/lists/xdp-newbies/msg01347.html
Further details about my system:
Driver: mlx5_core
Version: 25.07-0.9.7
FW Version: 22.46.3048 (MT_0000000359)
Kernel 6.14.0-35-generic