GoKawiilBenchmarks show musl libc lags glibc by up to 26% even with mimalloc swapped in
A developer investigating containerized Rust performance found that musl's default memory allocator is significantly slower than glibc's, not just under high concurrency but even on modest 4-core EC2 instances. Swapping in mimalloc or jemalloc narrows the gap but doesn't close it—one workload remained 26% slower—because several of musl's core memory routines are themselves inefficient, not just its allocator.