On Tue, Apr 27, 2021 at 8:28 PM Lorenzo Bianconi <lorenzo@xxxxxxxxxx> wrote: > > [...] > > > Took your patches for a test run with the AF_XDP sample xdpsock on an > > i40e card and the throughput degradation is between 2 to 6% depending > > on the setup and microbenchmark within xdpsock that is executed. And > > this is without sending any multi frame packets. Just single frame > > ones. Tirtha made changes to the i40e driver to support this new > > interface so that is being included in the measurements. > > > > What performance do you see with the mvneta card? How much are we > > willing to pay for this feature when it is not being used or can we in > > some way selectively turn it on only when needed? > > Hi Magnus, > > Today I carried out some comparison tests between bpf-next and bpf-next + > xdp_multibuff series on mvneta running xdp_rxq_info sample. Results are > basically aligned: > > bpf-next: > - xdp drop ~ 665Kpps > - xdp_tx ~ 291Kpps > - xdp_pass ~ 118Kpps > > bpf-next + xdp_multibuff: > - xdp drop ~ 672Kpps > - xdp_tx ~ 288Kpps > - xdp_pass ~ 118Kpps > > I am not sure if results are affected by the low power CPU, I will run some > tests on ixgbe card. Thanks Lorenzo. I made some new runs, this time with i40e driver changes as a new data point. Same baseline as before but with patches [1] and [2] applied. Note that if you use net or net-next and i40e, you need patch [3] too. The i40e multi-buffer support will be posted on the mailing list as a separate RFC patch so you can reproduce and review. Note, calculations are performed on non-truncated numbers. So 2 ns might be 5 cycles on my 2.1 GHz machine since 2.49 ns * 2.1 GHz = 5.229 cycles ~ 5 cycles. xdpsock is run in zero-copy mode so it uses the zero-copy driver data path in contrast with xdp_rxq_info that uses the regular driver data path. Only ran the busy-poll 1-core case this time. Reported numbers are the average over 3 runs. multi-buffer patches without any driver changes: xdpsock rxdrop 1-core: i40e: -4.5% in throughput / +3 ns / +6 cycles ice: -1.5% / +1 ns / +2 cycles xdp_rxq_info -a XDP_DROP i40e: -2.5% / +2 ns / +3 cycles ice: +6% / -3 ns / -7 cycles xdp_rxq_info -a XDP_TX i40e: -10% / +15 ns / +32 cycles ice: -9% / +14 ns / +29 cycles multi-buffer patches + i40e driver changes from Tirtha: xdpsock rxdrop 1-core: i40e: -3% / +2 ns / +3 cycles xdp_rxq_info -a XDP_DROP i40e: -7.5% / +5 ns / +9 cycles xdp_rxq_info -a XDP_TX i40e: -10% / +15 ns / +32 cycles Would be great if someone could rerun a similar set of experiments on i40e or ice then report. [1] https://lists.osuosl.org/pipermail/intel-wired-lan/Week-of-Mon-20210419/024106.html [2] https://lists.osuosl.org/pipermail/intel-wired-lan/Week-of-Mon-20210426/024135.html [3] https://lists.osuosl.org/pipermail/intel-wired-lan/Week-of-Mon-20210426/024129.html > Regards, > Lorenzo > > > > > Thanks: Magnus > > > > > Eelco Chaudron (4): > > > bpf: add multi-buff support to the bpf_xdp_adjust_tail() API > > > bpd: add multi-buffer support to xdp copy helpers > > > bpf: add new frame_length field to the XDP ctx > > > bpf: update xdp_adjust_tail selftest to include multi-buffer > > > > > > Lorenzo Bianconi (10): > > > xdp: introduce mb in xdp_buff/xdp_frame > > > xdp: add xdp_shared_info data structure > > > net: mvneta: update mb bit before passing the xdp buffer to eBPF layer > > > xdp: add multi-buff support to xdp_return_{buff/frame} > > > net: mvneta: add multi buffer support to XDP_TX > > > net: mvneta: enable jumbo frames for XDP > > > net: xdp: add multi-buff support to xdp_build_skb_from_fram > > > bpf: move user_size out of bpf_test_init > > > bpf: introduce multibuff support to bpf_prog_test_run_xdp() > > > bpf: test_run: add xdp_shared_info pointer in bpf_test_finish > > > signature > > > > > > drivers/net/ethernet/marvell/mvneta.c | 182 ++++++++++-------- > > > include/linux/filter.h | 7 + > > > include/net/xdp.h | 105 +++++++++- > > > include/uapi/linux/bpf.h | 1 + > > > net/bpf/test_run.c | 109 +++++++++-- > > > net/core/filter.c | 134 ++++++++++++- > > > net/core/xdp.c | 103 +++++++++- > > > tools/include/uapi/linux/bpf.h | 1 + > > > .../bpf/prog_tests/xdp_adjust_tail.c | 105 ++++++++++ > > > .../selftests/bpf/prog_tests/xdp_bpf2bpf.c | 127 ++++++++---- > > > .../bpf/progs/test_xdp_adjust_tail_grow.c | 17 +- > > > .../bpf/progs/test_xdp_adjust_tail_shrink.c | 32 ++- > > > .../selftests/bpf/progs/test_xdp_bpf2bpf.c | 3 +- > > > 13 files changed, 767 insertions(+), 159 deletions(-) > > > > > > -- > > > 2.30.2 > > >
