须要的!
为什么呢,以 python 的第三方协程实现 eventlet 为例子
看上面的代码:
from loguru import logger import eventlet # from eventlet.lock import Lock # eventlet.monkey_patch() var = 0 def foo(i): global var if var < 10: eventlet.sleep(1) var += 1 pool = eventlet.GreenPool() for body in pool.imap(foo, [i for i in range(100)]): pass logger.debug(f'最初的 {var}')
输入后果:
<code class="shell">╰─➤ time python -u "/Users/ponponon/Desktop/code/me/ideaboom/test_evenetlet/need_lock_with_sleep.py" 2022-06-29 23:33:03.015 | DEBUG | __main__:<module>:23 - 最初的 100 python -u 0.24s user 0.06s system 20% cpu 1.439 total
应用了锁之后,就失常了
from loguru import logger import eventlet from eventlet.lock import Lock # eventlet.monkey_patch() var = 0 lock=Lock() def foo(i): global var with lock: if var < 10: eventlet.sleep(1) var += 1 pool = eventlet.GreenPool() for body in pool.imap(foo, [i for i in range(100)]): pass logger.debug(f'最初的 {var}')
输入后果:
<code class="shell">╰─➤ time python -u "/Users/ponponon/Desktop/code/me/ideaboom/test_evenetlet/need_lock_with_sleep.py" 2022-06-29 23:31:35.865 | DEBUG | __main__:<module>:25 - 最初的 10 python -u 0.27s user 0.04s system 2% cpu 10.351 total