How much performance can you get out of JavaScript?

on YouTube ↗46m

" summary

Shows concrete limits and wins: benchmarks start with Node JS at ~6s versus C++ 1.5s (~4.5×), then fixing array bugs and preallocating brings JS to ~1.3s and C++ to 0.8s, an algorithmic change (stop at sqrt) cuts runtime to ~100ms (≈50×). Explains V8 mechanics — hidden classes, inline caches, ignition and turbofan — and tooling: Node/Chrome profilers and flags. Builds a 2000×2000 cell grid that works in JS but is much faster when memory layout is C++ style or compiled via Emscripten/WebAssembly.

AI-written summary · about

" chapters (12)

1. 0:00Start
2. 2:06A SIMPLE PROBLEM
3. 4:38HOW MUCH FASTER?
4. 5:12WE NEED TO BE PREPARED
5. 7:59HIDDEN CLASSES
6. 10:11FAST NUMBERS
7. 14:36OID THE SPEED TRAP
8. 22:41MORE ENGINES!
9. 30:22THE OPTIMIZING COMPILER
10. 33:38DEOPTIMIZATION
11. 34:30KNOW YOUR TOOLS
12. 35:00ARE YOU PREPARED?

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