:observer reports only 1 CPU (MacOS)

I’m on an 8-core i9 MacBook Pro :muscle: and tasks like compiling use all the cores, which is great. And System.schedulers_online reports 16, which is what I expect. But when I run :observer.start in iex, it reports just 1 CPU. Does this mean that my actual Elixir code is only getting 1 CPU? And if so, is there a config to tell it to use all available CPUs?

That’s odd maybe you should report that as a bug? Because from what I know there should 8 schedulers running on your machine. There are instructions how to do a bug report for Erlang/OTP at https://github.com/erlang/otp

can you upgrade to latest otp22 to rule out already fixed bugs/issues - also how do you start the beam? eg do you use docker or anything… how is erlang/elixir installed? (asdf?)


I see the same problem on erlang 23.0.2 and elixir 1.10.3-otp-23. Are there any solutions to this?

I think that’s just a display issue in Observer. Notice how many things are truncated? The ERTS version is cut off, the “used )” is missing under system limits, “true” is displayed as “tru”, etc. So it’s just that the “16” schedulers is being truncated as well, the “6” is missing.

It would be good if one of you could get a bug report going.