gevent支持的协程

Gevent 是一个第三方库，可以轻松通过gevent实现并发同步或异步编程，在gevent中用到的主要模式是Greenlet, 它是以C扩展模块形式接入Python的轻量级协程。 Greenlet全部运行在主程序操作系统进程的内部，但它们被协作式地调度。

import gevent

def foo():
    print('Running in foo')
    gevent.sleep(1)
    print('Explicit context switch to foo again')

def bar():
    print('Explicit context to bar')
    gevent.sleep(2)
    print('Implicit context switch to bar again')
gevent.joinall([
    gevent.spawn(foo),
    gevent.spawn(bar),
])

from gevent import monkey;

monkey.patch_all()
from urllib.request import urlopen
import time

def f(url):
    print('GET: %s' % url)
    resp = urlopen(url)
    data = resp.read()
    print('%d bytes received from %s.' % (len(data), url))

#l=['https://www.python.org/','https://www.baidu.com/','https://github.com/']
start=time.time()
# for url in l:
#     f(url)

gevent.joinall([
    gevent.spawn(f, 'https://www.python.org/'),
    gevent.spawn(f, 'https://www.baidu.com/'),
    gevent.spawn(f, 'https://github.com/'),
])

end=time.time()
print(end-start)