使用Bottlepy-Geven生成多个greenlets

Question

{py是一个新的异步编程教程。在

我运行了页面上给出的程序：

from gevent import monkey; monkey.patch_all()

from time import sleep
from bottle import route, run

@route('/stream')
def stream():
    yield 'START'
    sleep(3)
    yield 'MIDDLE'
    sleep(5)
    yield 'END'

run(host='0.0.0.0', port=8080, server='gevent')

当我访问URL http://localhost:8080/stream，打印START，然后是MIDDLE和{}时，它的工作与预期一样。在

根据文件

monkey patching enables gevent to prevent Python’s blocking APIs (and functions like time.sleep()) from blocking the current thread, and passes the CPU to the next greenlet instead.

但是，当我修改上面的代码以打印当前的greenlet信息时，我得到了用于所有三个yield语句的相同greenlet实例。在

^{pr2}$

控制台输出：

<Greenlet at 0x7f9fd733a9c8: _handle_and_close_when_done(<bound method WSGIServer.handle of <WSGIServer at , <bound method StreamServer.do_close of <WSGIServer, (<gevent._socket3.socket object, fd=7, family=2, t)>
<Greenlet at 0x7f9fd733a9c8: _handle_and_close_when_done(<bound method WSGIServer.handle of <WSGIServer at , <bound method StreamServer.do_close of <WSGIServer, (<gevent._socket3.socket object, fd=7, family=2, t)>
<Greenlet at 0x7f9fd733a9c8: _handle_and_close_when_done(<bound method WSGIServer.handle of <WSGIServer at , <bound method StreamServer.do_close of <WSGIServer, (<gevent._socket3.socket object, fd=7, family=2, t)>

根据bottlepy文档，每次时间。睡觉（）已执行？

此外，当我运行类似的程序而不使用gevent和monkey patching时，如下所示：

from time import sleep
from bottle import route, run

@route('/stream')
def stream():
    yield 'START \n'
    sleep(3)
    yield 'MIDDLE \n'
    sleep(5)
    yield 'END'

run(host='0.0.0.0', port=8080)

我得到了和以前一样的回答（开始后是中间，结束时间是3秒和5秒），与瓶装医生的评论相反，下面是黑体字：

If you run this script and point your browser to http://localhost:8080/stream, you should see START, MIDDLE, and END show up one by one (rather than waiting 8 seconds to see them all at once).

我是不是少了点什么？在

Answer 1

Per the bottlepy docs, shouldn't a new greenlet instance be spawned each time the time.sleep() is executed?

不，恐怕那里的药检有点混乱。在

为每个传入的HTTP请求生成一个新的greenlet。然后生成的greenlet从头到尾处理整个请求。如果这个greenlet产生（显式或隐式），那么另一个greenlet可以自由地做一些工作（大概是处理其他一些HTTP请求）。在

当您调用monkeypatchedtime.sleep时，正在处理HTTP请求的greenlet被挂起，从而产生任何其他活动的greenlet（如果有）。当time.sleep返回时（在指定的秒数之后），将唤醒先前为您的请求提供服务的greenlet，并从sleep调用之后恢复运行。在

希望有帮助！在

Answer 2

2个答案：

• 在同一个请求中，你将看到同一个请求。尝试同时发送几个请求，以查看更多的greelet的打印输出。在
• 您的例子适用于我的Mac和chrome瓶子文档说明您可能需要在某些浏览器上生成更多字节：

  Note: Some browsers buffer a certain amount of data before they start rendering a page. You might need to yield more than a few bytes to see an effect in these browsers. Additionally, many browsers have a limit of one concurrent connection per URL. If this is the case, you can use a second browser or a benchmark tool (e.g. ab or httperf) to measure performance.