This is a test to see if psycogreen is necessary to run sqlalchemy + gevent + psycopg2 concurrently.
ab -n 10 -c 10 127.0.0.1:8080/wait
gunicorn -b 127.0.0.1:8080 -w 2 test:app
Requests per second: 1.99 [#/sec] (mean)
gunicorn -b 127.0.0.1:8080 -w 2 test:app -k gevent
Requests per second: 1.98 [#/sec] (mean)
gunicorn -b 127.0.0.1:8080 -w 2 test:app -k gevent
Requests per second: 9.42 [#/sec] (mean)
Yes, psycogreen is required.