Gunicorn 'Green Unicorn' is a Python WSGI HTTP Server for UNIX
UWSGI is a fast, self-healing and developer/sysadmin-friendly application container server coded in pure C.
"I ve been using uwsgi in production on heroku for over a year and it seems to handle everything a lot better than gunicorn"
from question "How to optimize uWSGI for Heroku routers' proxy/buffering situation?"
"According to many benchmarks uwsgi seems to provides better performance than gunicorn and if the performance doesn t change significantly you ll be able to focus your investigation on nginx or ec2 configurations"
from question "Django + Gunicorn + nginx yields very poor performance. Can't get even 8 qps"