Erlang does automatically parallelize over multiple cores. By default it will start one Erlang VM thread per core which work together to run the Erlang system.

Erlang does automatically parallelize over multiple cores. By default it will start one Erlang VM thread per core which work together to run the Erlang system. The Erlang VM also does automatic load balancing over the threads and even tries to shut down threads/cores if it detects they are not needed. It is possible to control how many Erlang VM threads you want at start-up and to lock them to cores as well, though the latter is not recommended. But as I said there is no need to do this.