How to use multiprocessing at all?

[rubslopes]

Is there a tutorial? I searched a lot but I couldn't find one. But running the optimizer gives the message For multiprocessing support in Backtest.optimize() set multiprocessing start method to 'fork'.

I am a Mac user.

Thank you!

[kernc]

See Contexts and Start Methods in Python multiprocessing docs.

[rubslopes]

Thanks!

For anyone wondering, simply include this in your code:

import multiprocessing as mp
mp.set_start_method('fork')

This only works on Unix systems.

[stnatter]

tried this. getting: RuntimeError: context has already been set

[rubslopes]

You should run mp.set_start_method('fork') only once when importing. Don't run it again.

[curiouscod3]

import multiprocessing as mp

try:
    # mp.set_start_method("spawn", force=True)
    # print("spawned")
    mp.set_start_method("fork", force=True)
    print("forked")
except RuntimeError:
    pass

[lILogit]

It works also on iOS (MacBook Pro)