Dust Li says:
====================
net/smc: some datapath performance optimizations
This series tries to improve the performance of SMC in datapath.
- patch #1, add sysctl interface to support tuning the behaviour of
SMC in container environment.
- patch #2/#3, add autocorking support which is very efficient for small
messages without trade-off for latency.
- patch #4, send directly on setting TCP_NODELAY, without wake up the
TX worker, this make it consistent with clearing TCP_CORK.
- patch #5, this correct the setting of RMB window update limit, so
we don't send CDC messages to update peer's RMB window too frequently
in some cases.
- patch #6, implemented something like NAPI in SMC, decrease the number
of hardirq when busy.
- patch #7, this moves TX work doing in the BH to the user context when
sock_lock is hold by user.
With this patchset applied, we can get a good performance gain:
- qperf tcp_bw test has shown a great improvement. Other benchmarks like
'netperf TCP_STREAM' or 'sockperf throughput' has similar result.
- In my testing environment, running qperf tcp_bw and tcp_lat, SMC behaves
better then TCP in most all message size.
Here are some test results with the following testing command:
client: smc_run taskset -c 1 qperf smc-server -oo msg_size:1:64K:*2 \
-t 30 -vu tcp_{bw|lat}
server: smc_run taskset -c 1 qperf
==== Bandwidth ====
MsgSize Origin SMC TCP SMC with patches
1 0.578 MB/s 2.392 MB/s(313.57%) 2.561 MB/s(342.83%)
2 1.159 MB/s 4.780 MB/s(312.53%) 5.162 MB/s(345.46%)
4 2.283 MB/s 10.266 MB/s(349.77%) 10.122 MB/s(343.46%)
8 4.668 MB/s 19.040 MB/s(307.86%) 20.521 MB/s(339.59%)
16 9.147 MB/s 38.904 MB/s(325.31%) 40.823 MB/s(346.29%)
32 18.369 MB/s 79.587 MB/s(333.25%) 80.535 MB/s(338.42%)
64 36.562 MB/s 148.668 MB/s(306.61%) 158.170 MB/s(332.60%)
128 72.961 MB/s 274.913 MB/s(276.80%) 316.217 MB/s(333.41%)
256 144.705 MB/s 512.059 MB/s(253.86%) 626.019 MB/s(332.62%)
512 288.873 MB/s 884.977 MB/s(206.35%) 1221.596 MB/s(322.88%)
1024 574.180 MB/s 1337.736 MB/s(132.98%) 2203.156 MB/s(283.70%)
2048 1095.192 MB/s 1865.952 MB/s( 70.38%) 3036.448 MB/s(177.25%)
4096 2066.157 MB/s 2380.337 MB/s( 15.21%) 3834.271 MB/s( 85.58%)
8192 3717.198 MB/s 2733.073 MB/s(-26.47%) 4904.910 MB/s( 31.95%)
16384 4742.221 MB/s 2958.693 MB/s(-37.61%) 5220.272 MB/s( 10.08%)
32768 5349.550 MB/s 3061.285 MB/s(-42.77%) 5321.865 MB/s( -0.52%)
65536 5162.919 MB/s 3731.408 MB/s(-27.73%) 5245.021 MB/s( 1.59%)
==== Latency ====
MsgSize Origin SMC TCP SMC with patches
1 10.540 us 11.938 us( 13.26%) 10.356 us( -1.75%)
2 10.996 us 11.992 us( 9.06%) 10.073 us( -8.39%)
4 10.229 us 11.687 us( 14.25%) 9.996 us( -2.28%)
8 10.203 us 11.653 us( 14.21%) 10.063 us( -1.37%)
16 10.530 us 11.313 us( 7.44%) 10.013 us( -4.91%)
32 10.241 us 11.586 us( 13.13%) 10.081 us( -1.56%)
64 10.693 us 11.652 us( 8.97%) 9.986 us( -6.61%)
128 10.597 us 11.579 us( 9.27%) 10.262 us( -3.16%)
256 10.409 us 11.957 us( 14.87%) 10.148 us( -2.51%)
512 11.088 us 12.505 us( 12.78%) 10.206 us( -7.95%)
1024 11.240 us 12.255 us( 9.03%) 10.631 us( -5.42%)
2048 11.485 us 16.970 us( 47.76%) 10.981 us( -4.39%)
4096 12.077 us 13.948 us( 15.49%) 11.847 us( -1.90%)
8192 13.683 us 16.693 us( 22.00%) 13.336 us( -2.54%)
16384 16.470 us 23.615 us( 43.38%) 16.519 us( 0.30%)
32768 22.540 us 40.966 us( 81.75%) 22.452 us( -0.39%)
65536 34.192 us 73.003 us(113.51%) 33.916 us( -0.81%)
------------
Test environment notes:
1. Testing is run on 2 VMs within the same physical host
2. The NIC is ConnectX-4Lx, using SRIOV, and passing through 2 VFs to the
2 VMs respectively.
3. To decrease jitter, VM's vCPU are binded to each physical CPU, and those
physical CPUs are all isolated using boot parameter `isolcpus=xxx`
4. The queue number are set to 1, and interrupt from the queue is binded to
CPU0 in the guest
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
projects / platform / kernel / linux-rpi.git / commitdiff