mimalloc slower than glibc 2.30

Hi!

First of all, legendary work! I've been using mimalloc for https://github.com/PacificBiosciences/ccs to saturate 256 threads on those new AMD 2x7742 or 2x7H12 servers. I'm blown away how much faster it is, compared to glibc 2.32. Especially running with large os pages. There is one edge case, mimalloc is still slower than the arena allocator of the latest glibc, if I use it only a few threads like 16 on a large machine.

On a small dataset, using 16 threads:

On a dataset with 10x more data, using 256 threads:

I'm aware that's ricing, but in production, our run times are ~30 hours, so every percent wall time counts.

I build mimalloc from source

cmake -GNinja -DCMAKE_INSTALL_PREFIX:PATH=${FOO}/software ..
ninja -v
ninja install

and then link it statically

LDFLAGS="${FOO}/software/lib/mimalloc-1.6/libmimalloc.a"

My question, is there any way to tune mimalloc to be as fast as the latest glibc allocator for lower number of threads?

Thank you!
Armin

Riproduci il confronto riportato con 16 thread utilizzando i comandi di build CMake/Ninja e il linking statico di libmimalloc.a mostrati nell’issue. Confronta mimalloc con glibc 2.30 sui workload indicati e determina se è possibile identificare un’opzione di tuning documentata o un problema di performance riproducibile dell’allocator; il lavoro è considerato completato quando viene confermata una causa o un prossimo passo attuabile.