[Python知识库]python协程中for循环避免阻塞

直接上代码

#协程版
import asyncio
import time


async def func(a):
    t = await asyncio.sleep(1)
    return a+10

async def run():
    time_start = time.time()
    a_list = [1, 2, 3, 4]
    ans_list = await asyncio.gather(*[func(a=a) for a in a_list])
    for a, ans in zip(a_list, ans_list):
        print(a, ans)
    time_end = time.time()
    time_spend = time_end - time_start
    print('\n{0} cost time {1} s\n'.format(func.__name__, time_spend))

if __name__ == '__main__':
    loop = asyncio.get_event_loop()
    loop.run_until_complete(run())

结果：

#阻塞版
import asyncio
import time


def func(a):
    time.sleep(1)
    return a+10

async def run():
    time_start = time.time()
    a_list = [1, 2, 3, 4]
    ans_list = [func(a=a) for a in a_list]
    for a, ans in zip(a_list, ans_list):
        print(a, ans)
    time_end = time.time()
    time_spend = time_end - time_start
    print('\n{0} cost time {1} s\n'.format(func.__name__, time_spend))

if __name__ == '__main__':
    loop = asyncio.get_event_loop()
    loop.run_until_complete(run())

结果：

在协程中要尽量避免使用阻塞的写法。