Comment by masklinn
4 years ago
Client space scheduler and processes. The isolation is a property of the VM and langage primitives (you just don’t get any way to share stuff, kinda).
Also Erlang is known for cheap and plentiful processes, not for being fast. It’s fast enough but it’s no speed demon.
My reference to “fast” was in the context of creating a new process due to the OP post talking about how long fork/etc can take. Not in reference to executing code itself.
In that sense it’s fast in the same way e.g. coroutines(/goroutines) are fast: it’s just the erlang scheduler performing some allocation (possibly from a freelist) and initialisation. Avoiding the kernel having to set things up and the related context switches makes for much better performances.