Quote from the musl mailing list:
> The mallocng allocator was designed to favor very low memory overhead, low worst-case fragmentation cost, and strong hardening over performance. This is because it's much easier and safer to opt in to using a performance-oriented allocator for the few applications that are doing ridiculous things with malloc to make it a performance bottleneck than to opt out of trading safety for performance in every basic system utility that doesn't hammer malloc.