How to run in parallel using all CPUs from a laptop?

[iuryt]

While discussing with a student at IIT Madras (Chennai, India), she asked me how simple would be to run her simulation in parallel using the cores from her laptop. I just realized that I never tried that and we couldn't find an example on the docs while using the search engine.

I know this should be straightforward, maybe julia -p nproc simulation.jl?
Can we specify the number of the cores used within the code?

[glwagner]

The easiest way is to use the environment variable JULIA_NUM_THREADS. This can be specified in a config file like .zshrc or .bashrc, or when launching julia:

$ JULIA_NUM_THREADS=8 julia

See https://docs.julialang.org/en/v1/manual/multi-threading/