Link: https://pranitha.dev/posts/rust-and-memory-allocators/

While load testing one of our Rust services at work, we ran into something that took us way longer to figure out than we'd like to admit: memory that shoots up under load and just stays there.

Though glibc is the default allocator and works well for the majority of applications, it can retain significant allocator-owned memory for bursty workloads due to arena reuse, fragmentation, and cached free chunks.

Allocator switch, and this article was mentioned in Lemmy Release v0.19.20 - Reduced Memory Usage

This release significantly reduces memory usage for the Lemmy backend. Metrics on production instances show a reduction up to 10 times. Here you can see the statistics from a few different instances. Read on for a technical explanation below. Note that the change only affects x86, there is no difference on ARM (e.g. Raspberry Pi), see here for details.

Great write up. thanks for posting it was an interesting read.

I've never thought about what swapping out allocators would do in an async environment like that. Very readable and interesting!