In Tornado's chat demo, it has a method like this:
@tornado.web.asynchronous
def post(self):
cursor = self.get_argument("cursor", None)
global_message_buffer.wait_for_messages(self.on_new_messages,
cursor=cursor)
I'm fairly new to this long polling thing, and I don't really understand exactly how the threading stuff works, though it states:
By using non-blocking network I/O, Tornado can scale to tens of thousands of open connections...
My theory was that by making a simple app:
import tornado.ioloop
import tornado.web
import time
class MainHandler(tornado.web.RequestHandler):
@tornado.web.asynchronous
def get(self):
print("Start request")
time.sleep(4)
print("Okay done now")
self.write("Howdy howdy howdy")
self.finish()
application = tornado.web.Application([
(r'/', MainHandler),
])
That if I made two requests in a row (i.e. I opened two browser windows and quickly refreshed both) I would see this:
Start request
Start request
Okay done now
Okay done now
Instead, I see
Start request
Okay done now
Start request
Okay done now
Which leads me to believe that it is, in fact, blocking in this case. Why is it that my code is blocking, and how do I get some code to do what I expect? I get the same output on Windows 7 with a core i7, and a linux Mint 13 box with I think two cores.
Edit:
I found one method - if someone can provide a method that works cross-platform (I'm not too worried about performance, only that it's non-blocking), I'll accept that answer.
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