https://gist.github.com/1258543 re-implemented with http://eventlet.net/

block-eventlet.py

import eventlet
from eventlet import wsgi
from eventlet import sleep


def switch(it):
    for item in it:
        yield item
        sleep(0.0)


def _fib(n):
    a, b = 0, 1
    for i in xrange(n):
        yield a
        a, b = b, a + b



def fibonacci(n):
    return list(switch(_fib(n)))


def simple_app(environ, start_response):
    print("START RESPONSE")
    start_response('200 OK', [('Content-Type', 'text/plain')])
    r = repr(fibonacci(40))
    print("FIB(40): %r" % (r, ))
    return [r]

print "Serving on port 8000..."
wsgi.server(eventlet.listen(('', 8000)), simple_app)


---

$ ab -n 10 -c 5 http://127.0.0.1:8000/
...
Requests per second:    0.03 [#/sec] (mean)
...