Guangguan Wang says:
====================
net/smc: send and write inline optimization for smc
Send cdc msgs and write data inline if qp has sufficent inline
space, helps latency reducing.
In my test environment, which are 2 VMs running on the same
physical host and whose NICs(ConnectX-4Lx) are working on
SR-IOV mode, qperf shows 0.4us-1.3us improvement in latency.
Test command:
server: smc_run taskset -c 1 qperf
client: smc_run taskset -c 1 qperf <server ip> -oo \
msg_size:1:2K:*2 -t 30 -vu tcp_lat
The results shown below:
msgsize before after
1B 11.9 us 10.6 us (-1.3 us)
2B 11.7 us 10.7 us (-1.0 us)
4B 11.7 us 10.7 us (-1.0 us)
8B 11.6 us 10.6 us (-1.0 us)
16B 11.7 us 10.7 us (-1.0 us)
32B 11.7 us 10.6 us (-1.1 us)
64B 11.7 us 11.2 us (-0.5 us)
128B 11.6 us 11.2 us (-0.4 us)
256B 11.8 us 11.2 us (-0.6 us)
512B 11.8 us 11.3 us (-0.5 us)
1KB 11.9 us 11.5 us (-0.4 us)
2KB 12.1 us 11.5 us (-0.6 us)
====================
Link: https://lore.kernel.org/r/20220516055137.51873-1-guangguan.wang@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>