Is cryptsetup benchmark for single or multiple queues

Question

Let say that cryptsetup benchmarks gives 2 GiB/s performance. Is it per queue so on 4 core processor I could read from disk at 8 GiB/s (assuming I wasn't limited by SATA etc. and it would scale perfectly) or does it already take it into account?

Answer 1

cryptsetup benchmark only uses a single core. You can see this in top while it's running, it never goes beyond 100% of one core only.

I'm not quite sure how cryptsetup benchmark performance relates to actual performance on physical storage media; a tmpfs based loop device gives 2GiB/s according to pv, while the benchmark says 2666.5 MiB/s.

So expect slightly lower speeds than the benchmark claims.

As for scaling to multiple cores, not sure if that's a thing nowadays. I guess no since if it was I'd expect the cryptsetup benchmark to scale accordingly, too. But that's just a guess. Used to be you had to use multiple LUKS containers (and multiple readers on those containers) to get multiple cores working on encryption.