multiprocessing_multiple_bars_tqdm.py

"""
The MIT License

Copyright (c) 2020 Mark Douthwaite
"""

import time
import multiprocessing as mp
from tqdm import tqdm


def my_process(pos: int) -> None:
    """Dummy process, where 'pos' is the position of the associated progress bar."""
    
    with tqdm(desc=f"Process {pos}", total=100, position=pos) as progress:
        for _ in range(100):
            time.sleep(0.1)
            progress.update(1)


if __name__ == "__main__":

    n_cpu = mp.cpu_count()

    # `tqdm` needs to get the global lock to avoid the progress bars 'jumping' 
    with mp.Pool(
        processes=n_cpu, initializer=tqdm.set_lock, initargs=(tqdm.get_lock(),)
    ) as pool:
        pool.map(my_process, range(n_cpu))