I am trying to be able to respond incoming web requests simultaneously, while processing of a request includes quite long IO call. I'm going to use gevent, as it's supposed to be "non-blocking"
The problem I found is that requests are processed sequentially even though I have a lot of gevent threads. For some reason requests get served by single green thread.
I have nginx (with default config which isn't relevant here I think), also I have uwsgi and simple wsgi app that emulates IO-blocking call as gevent.sleep(). Here they are:
uwsgi.ini
[uwsgi]
chdir = /srv/website
home = /srv/website/env
module = wsgi:app
socket = /tmp/uwsgi_mead.sock
#daemonize = /data/work/zx900/mob-effect.mead/logs/uwsgi.log
processes = 1
gevent = 100
gevent-monkey-patch
wsgi.py
import gevent
import time
from flask import Flask
app = Flask(__name__)
@app.route("/")
def hello():
t0 = time.time()
gevent.sleep(10.0)
t1 = time.time()
return "{1} - {0} = {2}".format(t0, t1, t1 - t0)
then I simultaneously (almost) open two tabs in my browser, and here is what I get as result:
1392297388.98 - 1392297378.98 = 10.0021491051
# first tab, processing finished at 1392297378.98
1392297398.99 - 1392297388.99 = 10.0081849098
# second tab, processing started at 1392297398.99
As you can see, first call blocked execution of the view. What did I wrong?
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