React 18 + Next.js performs worse than React 17 + Next.js. This is across Next.js 12 and 13. This is not the case with raw React renderToString(), React 18 has better performance in comparison to React 17 when Next.js is omitted - Separate React specific benchmarks here: https://github.com/SuperOleg39/react-ssr-perf-test
Stats summary:
| Stat | Next.js 12 / React 17 | Next.js 12 / React 18 | Next.js 13 / React 18 |
|---|---|---|---|
| Average Requests Per Second (higher is better) | 22.8 | 18.3 (-19.7%) | 17 (-25.4%) |
| Average Latency (lower is better) | 2436.85 ms | 3303.44 ms (-35.5%) | 3171.23 ms (-27.3%) |
The following test results are obtained from a 2.3GHz Quad-Core Intel MacBook Pro running Node.js 16. Similar results have also been reproduced in other environments (eg Azure Linux).
Navigate to the relevant project you want to performance test eg cd nextjs-12-react-17 and run npm install
- Run the Next.js application
npm run build && npm start - Run perf test
npx autocannon -c 50 -d 10 http://localhost:3000/ --renderStatusCodes --excludeErrorStats- you can also run it multiple times if you are concerned about Node not being warm (JIT optimizations).
Running 10s test @ http://localhost:3000/
50 connections
┌─────────┬────────┬─────────┬─────────┬─────────┬────────────┬───────────┬─────────┐
│ Stat │ 2.5% │ 50% │ 97.5% │ 99% │ Avg │ Stdev │ Max │
├─────────┼────────┼─────────┼─────────┼─────────┼────────────┼───────────┼─────────┤
│ Latency │ 228 ms │ 2744 ms │ 3241 ms │ 3305 ms │ 2436.85 ms │ 924.25 ms │ 3355 ms │
└─────────┴────────┴─────────┴─────────┴─────────┴────────────┴───────────┴─────────┘
┌───────────┬────────┬────────┬─────────┬─────────┬─────────┬─────────┬────────┐
│ Stat │ 1% │ 2.5% │ 50% │ 97.5% │ Avg │ Stdev │ Min │
├───────────┼────────┼────────┼─────────┼─────────┼─────────┼─────────┼────────┤
│ Req/Sec │ 1 │ 1 │ 18 │ 64 │ 17.8 │ 17.19 │ 1 │
├───────────┼────────┼────────┼─────────┼─────────┼─────────┼─────────┼────────┤
│ Bytes/Sec │ 263 kB │ 263 kB │ 4.73 MB │ 16.8 MB │ 4.68 MB │ 4.51 MB │ 263 kB │
└───────────┴────────┴────────┴─────────┴─────────┴─────────┴─────────┴────────┘
┌──────┬───────┐
│ Code │ Count │
├──────┼───────┤
│ 200 │ 178 │
└──────┴───────┘
Req/Bytes counts sampled once per second.
# of samples: 10
228 requests in 10.02s, 46.8 MB read
Running 10s test @ http://localhost:3000/
50 connections
┌─────────┬─────────┬─────────┬─────────┬─────────┬────────────┬───────────┬─────────┐
│ Stat │ 2.5% │ 50% │ 97.5% │ 99% │ Avg │ Stdev │ Max │
├─────────┼─────────┼─────────┼─────────┼─────────┼────────────┼───────────┼─────────┤
│ Latency │ 1437 ms │ 3050 ms │ 5219 ms │ 5219 ms │ 3303.44 ms │ 1113.5 ms │ 7284 ms │
└─────────┴─────────┴─────────┴─────────┴─────────┴────────────┴───────────┴─────────┘
┌───────────┬─────┬──────┬────────┬─────────┬────────┬─────────┬────────┐
│ Stat │ 1% │ 2.5% │ 50% │ 97.5% │ Avg │ Stdev │ Min │
├───────────┼─────┼──────┼────────┼─────────┼────────┼─────────┼────────┤
│ Req/Sec │ 0 │ 0 │ 3 │ 39 │ 13.3 │ 13.39 │ 1 │
├───────────┼─────┼──────┼────────┼─────────┼────────┼─────────┼────────┤
│ Bytes/Sec │ 0 B │ 0 B │ 788 kB │ 10.3 MB │ 3.5 MB │ 3.52 MB │ 263 kB │
└───────────┴─────┴──────┴────────┴─────────┴────────┴─────────┴────────┘
┌──────┬───────┐
│ Code │ Count │
├──────┼───────┤
│ 200 │ 133 │
└──────┴───────┘
Req/Bytes counts sampled once per second.
# of samples: 10
183 requests in 10.04s, 35 MB read
Running 10s test @ http://localhost:3000/
50 connections
┌─────────┬─────────┬─────────┬─────────┬─────────┬────────────┬─────────┬─────────┐
│ Stat │ 2.5% │ 50% │ 97.5% │ 99% │ Avg │ Stdev │ Max │
├─────────┼─────────┼─────────┼─────────┼─────────┼────────────┼─────────┼─────────┤
│ Latency │ 1042 ms │ 3348 ms │ 4865 ms │ 5200 ms │ 3171.23 ms │ 1089 ms │ 6489 ms │
└─────────┴─────────┴─────────┴─────────┴─────────┴────────────┴─────────┴─────────┘
┌───────────┬─────┬──────┬─────────┬────────┬─────────┬─────────┬────────┐
│ Stat │ 1% │ 2.5% │ 50% │ 97.5% │ Avg │ Stdev │ Min │
├───────────┼─────┼──────┼─────────┼────────┼─────────┼─────────┼────────┤
│ Req/Sec │ 0 │ 0 │ 9 │ 27 │ 12 │ 10.18 │ 2 │
├───────────┼─────┼──────┼─────────┼────────┼─────────┼─────────┼────────┤
│ Bytes/Sec │ 0 B │ 0 B │ 2.37 MB │ 7.1 MB │ 3.15 MB │ 2.68 MB │ 526 kB │
└───────────┴─────┴──────┴─────────┴────────┴─────────┴─────────┴────────┘
┌──────┬───────┐
│ Code │ Count │
├──────┼───────┤
│ 200 │ 120 │
└──────┴───────┘
Req/Bytes counts sampled once per second.
# of samples: 10
170 requests in 10.03s, 31.5 MB read