perf(wasm): speed up Zstd compression - #251
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LLVM's min-size profile keeps the inlining threshold too low for the Zstd hot path. Raise only that threshold for libdatadog-wasm, enable SIMD, and use Binaryen -O3 on the resulting module. Node 24.20.0 measured 7.2–20.9% faster compression for 1 MiB inputs and 4.9–13.6% for 4 MiB inputs. Brotli size decreases by 0.07%, while gzip size grows by 0.60%.
Overall package sizeSelf size: 31.65 MB Dependency sizes| name | version | self size | total size | |------|---------|-----------|------------|🤖 This report was automatically generated by heaviest-objects-in-the-universe |
BridgeAR
marked this pull request as ready for review
September 3, 2026 20:32
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Summary
simd128forlibdatadog-wasm-C llvm-args=-inline-threshold=45while retaining Rust'sopt-level = "z"-O3, which produced the smallest compressed candidate in the optimization sweepResults
Node 24.20.0 measured 7.2–20.9% faster Zstd compression for 1 MiB inputs and 4.9–13.6% for 4 MiB inputs. The benchmark used seven interleaved trials after warmup in fresh and reversed orders.
Raw WASM grew 2.47%. Brotli size decreased 0.07%, and gzip size grew 0.60%.
Zstd and DDSketch outputs remained byte-identical. Node 18.20.8 loaded and executed the SIMD build.
Verification
npm run lintnpm test