python使用ProcessPoolExecutor问题总结

python版本：3.7.10

• 进程池启动需要从主进入__name__=="__mian__'
• 进程池的future任务函数不能用装饰器

使用示例：

def consume(a=1):
    def wrapper(func):
        def _inner(*args, **kwargs):
            import time
            s = time.time()
            func(*args, **kwargs)
            e = time.time()
            print(f'{a}耗时:', e - s)

        return _inner

    return wrapper


@consume
def te(times):
    time.sleep(times)
    import os #获取pid必须在局部导入os
    pid = os.getpid()
    print(f'pid:{pid}被装饰函数{times}')
def tes(b):
    te(b)

if __name__ == '__main__':#进程池要求这样做
    from concurrent.futures import ThreadPoolExecutor, wait, ALL_COMPLETED
    from concurrent.futures import ProcessPoolExecutor, Executor
    import multiprocessing

    cup_num = multiprocessing.cpu_count()
    print(cup_num)
    # exec = ThreadPoolExecutor(max_workers=2, thread_name_prefix='pythonThreadPool')
    # exec = ProcessPoolExecutor(max_workers=cup_num)
    # with ThreadPoolExecutor(max_workers=cup_num) as exec:
    with ProcessPoolExecutor(max_workers=cup_num) as exec:
        exec.map(te, range(10))
        # tasks = [exec.submit(te, i) for i in range(10)]
    # wait(tasks, return_when=ALL_COMPLETED)
    # exec.shutdown()