On 11/30/21 8:18 AM, Pavel Begunkov wrote: > Early proof of concept for zerocopy send via io_uring. This is just > an RFC, there are details yet to be figured out, but hope to gather > some feedback. > > Benchmarking udp (65435 bytes) with a dummy net device (mtu=0xffff): > The best case io_uring=116079 MB/s vs msg_zerocopy=47421 MB/s, > or 2.44 times faster. > > № | test: | BW (MB/s) | speedup > 1 | msg_zerocopy (non-zc) | 18281 | 0.38 > 2 | msg_zerocopy -z (baseline) | 47421 | 1 > 3 | io_uring (@flush=false, nr_reqs=1) | 96534 | 2.03 > 4 | io_uring (@flush=true, nr_reqs=1) | 89310 | 1.88 > 5 | io_uring (@flush=false, nr_reqs=8) | 116079 | 2.44 > 6 | io_uring (@flush=true, nr_reqs=8) | 109722 | 2.31 > > Based on selftests/.../msg_zerocopy but more limited. You can use > msg_zerocopy -r as usual for receive side. > ... Can you state the exact command lines you are running for all of the commands? I tried this set (and commands referenced below) and my mileage varies quite a bit. Also, have you run this proposed change (and with TCP) across nodes (ie., not just local process to local process via dummy interface)? > Benchmark: > https://github.com/isilence/liburing.git zc_v1 > > or this file in particular: > https://github.com/isilence/liburing/blob/zc_v1/test/send-zc.c > > To run the benchmark: > ``` > cd <liburing_dir> && make && cd test > # ./send-zc -4 [-p <port>] [-s <payload_size>] -D <destination> udp > ./send-zc -4 -D 127.0.0.1 udp > ``` > > msg_zerocopy can be used for the server side, e.g. > ``` > cd <linux-kernel>/tools/testing/selftests/net && make > ./msg_zerocopy -4 -r [-p <port>] [-t <sec>] udp > ``` >
