【Python】同步与异步

# 提交任务的两种方式
# 1.同步调用:调用任务后, 原地等待任务执行完毕,
#   导致程序串行执行
import time, random
from concurrent.futures import ThreadPoolExecutor


def la(name):
    print('%s is pooping' % name)
    time.sleep(random.randint(3, 5))
    res = random.randint(7, 13) * '#'
    return {'name': name, 'res': res}



def weight(crap):   #crap 是一个 Futures 对象
    crap = crap.result()
    name = crap['name']
    size = len(crap['res'])
    print('%s pooped [%s] kg' % (name, size))


# if __name__ == '__main__':
#     pool = ThreadPoolExecutor(12)
#     start = time.time()
#     for i in range(133):
#         crap = pool.submit(la, 'member-%s' % i).result()
#         weight(crap)
#     stop = time.time()
#     print(stop - start)  # 500s


# 2.异步调用:调用任务后, 不等待,任务执行随意,
#   程序并行执行

if __name__ == '__main__':
    pool = ThreadPoolExecutor(12)
    start = time.time()
    for i in range(133):
        p = pool.submit(la, 'member-%s' % i)
        p.add_done_callback(weight)
    pool.shutdown()
    stop = time.time()
    print(stop - start)   # 46s