[Python] I/O Bound(2) - Asyncio basic

비동기 기초 샘플 코드

 

동시 프로그래밍 패러다임 변화
싱글코어 -> 처리향상 미미, 저하 -> 비동기 프로그래밍 
-> CPU연산, DB연동, API호출 대기 시간 늘어남 => 논블로킹으로 변환

파이썬에서 비동기 프로그래밍은 개념을 잘 잡아야 함.
파이썬 3.4에서 비동기(asyncio) 표준라이브러리 등장

 

import time
import asyncio

async def exe_calculate_async(name, n):
    for i in range(1, n + 1):
        print(f'{name} -> {i} of {n} is calculating..')
        # time.sleep(1) # 동기 처리, 시간비교하기 좋음
        await asyncio.sleep(1) # 비동기 처리, 시간비교하기 좋음
    print(f'>{name} - {n} working done!')
    print()
    
async def process_async():
    start = time.time()
    await asyncio.wait([
        exe_calculate_async('One', 3),
        exe_calculate_async('Two', 2),
        exe_calculate_async('Three', 1),
    ])
    end = time.time()
    print(f'>>> total seconds : {end - start}')


def exe_calculate_sync(name, n):
    for i in range(1, n + 1):
        print(f'{name} -> {i} of {n} is calculating..')
        time.sleep(1)
    print(f'>{name} - {n} working done!')
    print()


def process_sync():
    start = time.time()
    
    exe_calculate_sync('One', 3)
    exe_calculate_sync('Two', 2)
    exe_calculate_sync('Three', 1)
    
    end = time.time()
    print(f'>>> total seconds : {end - start}')

if __name__ == '__main__':
    # Sync 실행
    # process_sync()
    
    
    # Async 실행
    asyncio.run(process_async()) # 3.7 이상, 3.8에서 버그 있음.
    # asyncio.get_event_loop().run_until_complete(process_async()) # 3.7 미만
    
----------------------------------------[result]    
# time.sleep(1) 동기처리로 실행한 경우
Two -> 1 of 2 is calculating..
Two -> 2 of 2 is calculating..
>Two - 2 working done!

One -> 1 of 3 is calculating..
One -> 2 of 3 is calculating..
One -> 3 of 3 is calculating..
>One - 3 working done!

Three -> 1 of 1 is calculating..
>Three - 1 working done!

>>> total seconds : 6.049928188323975

# await asyncio.sleep(1) 비동기처리로 실행한 경우
Two -> 1 of 2 is calculating..
One -> 1 of 3 is calculating..
Three -> 1 of 1 is calculating..
Two -> 2 of 2 is calculating..
One -> 2 of 3 is calculating..
>Three - 1 working done!

>Two - 2 working done!

One -> 3 of 3 is calculating..
>One - 3 working done!

>>> total seconds : 3.021606206893921