alt Hacker NewsThe 26% number at the top of the article is from using mimalloc (which is a high performance allocator, at least as fast as the glibc allocator) + musl for some task, and the slowdown is coming from (probably) slow musl implementations of memcpy/memset. The musl allocator is even worse.
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Joker_vD • today at 5:24 PM
> the slowdown is coming from (probably) slow musl implementations of memcpy/memset.
It's wild that such a fundamental piece of code (you can't really implement operation on structs without those) is library-supplied. I wish compilers would just have something like __builtin_memcpy and __builtin_memset, and provided some highly optimized, specialist-crafted assembly in those, instead of having to inline the library code and hopefully be able to optimize it.
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Yeah, doing compute-heavy work a couple of jobs ago, we tried small images with musl, and the default allocator was a catastrophe: 75%+ slowdowns for our real life tasks. Even with a better allocator, we were way better off with the larger image.