The Erlang VM is plenty fast for starting stuff up that is long running, but I wouldn't use if for things that you need to launch 100's of times per second. But that's also not how it is intended to be used. As for the other kind of fast: number crunching performance is not what Erlang is for. It's for long running complex applications with a lot of moving parts, redundancy and extreme reliability.

Numerical Elixir (NX)[1] is improving the number crunching situation!

[1]: https://github.com/elixir-nx/nx/tree/main/nx#readme

I know about Podman, I just wanted to focus on systemd without additional tooling.

Erlang VM startup is ok, but it is not ultra fast, and it can be easily slowed down with many modules in releases or slow applications. Additionally as it was said - Erlang works best in case of long-running instances where the VM is handling spawning and managing of short lived internal processes.

First draft of this article also included the socket activation and FD passing section, but these were making the article way to long, so I moved them to the Part 2 where I will have more space for them. With socket activation Erlang VM startup time is negligible problem.

Yes it does start fairly quick, nothing like the JVM. It's not nearly as fast while it's running, though. It only recently got a JIT, and currently doesn't do any optimization of the generated code.

It's pretty quick on startup in my experience.