Research-Stack/4-Infrastructure/servo-fetch/benchmarks

Benchmarks

Resource usage comparison of tools that execute JavaScript and render web pages.

Results

Single page (https://example.com)

Tool	Peak RSS	Time
curl (no JS)	3 MB	0.17s
servo-fetch	64 MB	0.47s
Playwright	224 MB	0.82s
Puppeteer	590 MB	1.60s

4 pages parallel

Tool	Peak RSS	Time
servo-fetch	114 MB	1.50s
Playwright	502 MB	3.26s
Puppeteer	1065 MB	4.27s

Key takeaways

• vs Playwright: 3.5× less memory, 1.7–2.2× faster
• vs Puppeteer: 9× less memory, 2.8–3.4× faster
• Per additional page: servo-fetch ~17 MB, Playwright ~93 MB, Puppeteer ~158 MB

Methodology

Task

All tools perform the same operation: navigate to a URL, wait for the load event (JavaScript executed), and extract document.body.innerText. For the parallel test, all URLs are fetched concurrently.

Memory measurement

Peak RSS (Resident Set Size) of the entire process tree — the target process plus all its descendants. Chromium spawns separate renderer processes per page; all are included.

We sample every 50ms using a recursive pgrep -P walk. See run_benchmark.sh for the implementation.

On Linux, smem (PSS) would be more precise for shared memory. macOS does not expose PSS, so we use RSS. This slightly overcounts shared libraries in Chromium's multi-process architecture, but reflects actual system memory pressure (what the OOM killer sees).

Procedure

1. Warmup: 1 run discarded (DNS cache, disk cache, JIT warmup)
2. Measurement: 3 runs, median reported
3. Sampling: process tree RSS polled every 50ms; peak value recorded
4. Timing: wall-clock via time.time() delta

Test machine

• Hardware: Apple M3 Pro, 18 GB RAM
• OS: macOS (arm64)

Versions

Run ./run_benchmark.sh to see exact versions. The script auto-detects and prints all tool versions at the top of its output.

Reproduction

# 1. Build servo-fetch
cargo build --release

# 2. Install comparison tools
cd benchmarks/playwright && npm install && npx playwright install chromium && cd ..
cd puppeteer && npm install && cd ..

# 3. Run
./run_benchmark.sh