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Author ezwelty
Recipients ezwelty, ned.deily, ronaldoussoren, terry.reedy
Date 2018-03-27.04:16:29
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <>
Terry Reedy: I just tried your suggestion of a main clause (code below) and it made no difference.

import _tkinter
import numpy as np
# multiprocessing.set_start_method("spawn")
import multiprocessing

def parallel_matmul(x):
    R = np.random.randn(3, 3)
    return np.matmul(R, x)

if __name__ == '__main__':
    pool = multiprocessing.Pool(4)
    results =, [np.random.randn(3, 5000) for i in range(2)])

Ronald Oussoren: Good to know that perhaps upgrading to the latest OSX would resolve this issue. I tried 'spawn' and 'forkserver' with multiprocessing.set_start_method() (see above) but both result in an endless stream of errors (with or without importing a graphics backend), although that may be my not knowing how to properly use them.
Date User Action Args
2018-03-27 04:16:30ezweltysetrecipients: + ezwelty, terry.reedy, ronaldoussoren, ned.deily
2018-03-27 04:16:30ezweltysetmessageid: <>
2018-03-27 04:16:30ezweltylinkissue33111 messages
2018-03-27 04:16:29ezweltycreate