I'm having trouble getting this example working. In serial this function works just fine, but when I attempt to run it in a multiprocessing.Pool it locks up and will not return a simple random integer. I'm specifically using the spawn context because I'm developing in a Windows environment. import multiprocessing from tqdm import tqdm def test_parallel(min_rng: int): import random return random.randint(min_rng, 100) def bootstrap_test_parallel(n_tasks: int = 10_000, min_rng: int = 3, pool_size: int = max(1, multiprocessing.cpu_count() - 1)): results = [None for _ in range(n_tasks)] def log_result(value, ix): results[ix] = value if pool_size == 1: for ix in tqdm(range(n_tasks)): log_result(test_parallel(min_rng), ix) else: with multiprocessing.get_context("spawn").Pool(pool_size) as pool: for ix in tqdm(range(n_tasks)): log_result(pool.apply_async(test_parallel, args=(min_rng,)), ix=ix) for ix in tqdm(range(n_tasks)): results[ix] = results[ix].get() return results output_one = bootstrap_test_parallel(n_tasks=10, pool_size=1) # runs fine print(output_one) output_two = bootstrap_test_parallel(n_tasks=10, pool_size=2) # hangs indefinitely print(output_two) Continue reading...
