"Performance Matters" by Emery Berger

What people said

j-pb · 2023-06 · Strong recommendation

Nobody should do benchmarking like this anymore. Memory layout of your code has such a big impact on performance on modern computers that measuring performance without removing that variable leads to wild goose chases, where you think you improved something, but in reality you incidentally got the compiler to move the code around a bit. Emery Berger has an excelent talk on this [1], and a causal profiler that they developed called Coz[2]. Branch miss-predicts might be somewhat invariant to that, but still, one of the main points of the talk is that people do too much eyeball statistics, mistaking the variance of the underlying stochastic process with actual signal. Coz is pretty trivial to set up with Zig too. 1. [VIDEO] 2. [LINK]

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acidbaseextract · 2020-12 · Strong recommendation

I would highly recommend Emery Berger's talks [1] for anyone interested in benchmarking software. The alignment and code layout in memory that huayra mentions has shockingly large performance implications. [1] [VIDEO]

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robocat · 2020-05 · Strong recommendation

Aside: this is the most amazing optimisation information I have seen: [VIDEO] Unfortunate that it is a video... Summary: Modern CPUs have so many hidden causes of performance variation, that you require special tools to actually measure small performance gains. He finds an amazing but unobvious speed up in SQLite using the causal analysis tool they developed. And a surprising difference between -O2 and -O3 implying overfitting.

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