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"Works on contingency? No, money down!"

you can mail hn@ycombinator.com and they can change it for you to whatever.

What's the TLDR on how... hardware performs differently on two software runtimes?

AMD's implementation of `rep movsb` instruction is surprisingly slow when addresses are page aligned. Python's allocator happens to add a 16-byte offset that avoids the hardware quirk/bug.

thank you, upvoted!

One of the very first things in the article is a TLDR section that points you to the conclusion.

> In conclusion, the issue isn't software-related. Python outperforms C/Rust due to an AMD CPU bug.

It is software-related. Just the CPU perform badly on some software instruction.

FSRM is a CPU feature embedded in the microcode (in this instance, amd-ucode) that software such as glibc cannot interact with. I refer to it as hardware because I consider microcode a part of the hardware.