Jimmy Lai
663c9151cf
## Summary Benchmark infrastructure for measuring render pipeline performance. - **render-pipeline benchmark** (`bench/render-pipeline/`): `benchmark.ts` for profiling render paths, `analyze-profiles.ts` for CPU profile analysis - **Stress routes** (`bench/basic-app/app/streaming/`): light, medium, heavy, bulk, wide, chunkstorm variants for different streaming load profiles - **Basic app harness**: `benchmark.sh` runner script, `next.config.js` - **Minimal server**: `bench/next-minimal-server/bin/minimal-server.js` - **Docs**: `bench/BENCHMARKING.md` guide - **Config**: eslint exclusion for bench paths, package.json bench scripts ## Test plan - [ ] No runtime behavior changes - [ ] Benchmark scripts are standalone tooling --------- Co-authored-by: Tim Neutkens <tim@timneutkens.nl>
Render Pipeline Benchmark
This benchmark targets the full App Router render path (renderToHTMLOrFlight) via real HTTP requests through bench/next-minimal-server.
It supports:
webvsnodestreams mode comparison- route-based stress suites for streaming SSR
- CPU/heap profiling for the server process
- Node trace events and Next internal trace artifact capture
Quick start
Run end-to-end benchmark (default stress routes):
pnpm bench:render-pipeline --scenario=full --stream-mode=both
For scenario=full and scenario=all, CPU profiles are captured by default.
Disable with --capture-cpu=false if you want lower-overhead runs.
Skip rebuild for faster iteration (after you already built once):
pnpm bench:render-pipeline --scenario=full --stream-mode=node --build-full=false
When --stream-mode=both, the runner forces --build-full=true so web/node
comparisons do not accidentally reuse stale build output.
Output JSON report:
pnpm bench:render-pipeline --scenario=full --stream-mode=both --json-out=/tmp/render-pipeline.json
Profiling and traces
Capture CPU profiles + Node trace events + Next trace logs:
pnpm bench:render-pipeline \
--scenario=full \
--stream-mode=both \
--capture-trace=true \
--capture-next-trace=true
Artifacts are written to:
bench/render-pipeline/artifacts/<timestamp>/
Per mode (web and node) this includes:
<mode>.cpuprofile(if--capture-cpu=true)<mode>.heapprofile(if--capture-heap=true)<mode>-trace-*.json(if--capture-trace=true)next-trace-build.logandnext-runtime-trace.log(if--capture-next-trace=true)
Open .cpuprofile files in Chrome DevTools Performance panel.
Analyze results and CPU hotspots from artifacts:
pnpm bench:render-pipeline:analyze --artifact-dir=bench/render-pipeline/artifacts/<timestamp>
Omit --artifact-dir to analyze the latest run automatically.
Stress routes
Default routes:
//streaming/light/streaming/medium/streaming/heavy/streaming/chunkstorm/streaming/wide/streaming/bulk
The streaming/* pages now include a client boundary per Suspense chunk, so benchmark runs also stress Server-to-Client payload serialization in Flight data.
Override with:
pnpm bench:render-pipeline --scenario=full --routes=/,/streaming/heavy
Common tuning flags
--warmup-requests=30--serial-requests=120--load-requests=1200--load-concurrency=80--timeout-ms=30000--port=3199
Optional micro benchmarks
The runner also supports helper-only micro benchmarks:
pnpm bench:render-pipeline --scenario=micro