django - gunicorn + nginx: Server via socket or proxy?

Question

I've seen two strategies for hosting a django application with gunicorn and nginx.

One strategy is to run gunicorn on a network port. For example (from http://goodcode.io/blog/django-nginx-gunicorn/):

location / {
    proxy_pass_header Server;
    proxy_set_header Host $http_host;
    proxy_redirect off;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Scheme $scheme;
    proxy_connect_timeout 10;
    proxy_read_timeout 10;
    proxy_pass http://localhost:8000/;
}

Another strategy is to bind gunicorn to a UNIX socket on startup (e.g. http://michal.karzynski.pl/blog/2013/06/09/django-nginx-gunicorn-virtualenv-supervisor/)

upstream hello_app_server {
    server unix:/tmp/gunicorn.sock fail_timeout=0;
}

...

location / {
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header Host $http_host;
    proxy_redirect off;
    if (!-f $request_filename) {
        proxy_pass http://hello_app_server;
        break;
    }
}

Thoughts on which strategy is superior? Any any comments on the proper way to do each? I am leaning towards the socket approach because of the overhead I imagine is introduced by TCP. I am most concerned about the differences about headers, connect timeouts and such between implementation examples I have seen.

question from:https://stackoverflow.com/questions/19916016/gunicorn-nginx-server-via-socket-or-proxy

Answer 1

Besides the small TCP/IP overhead, there's not much of a difference. Each listen() socket gets a connection queue, and accept() just pops a connection from that queue. In gunicorn each worker just pops a new connection from that queue as its able so that won't change. The difference is performance (sockets being a bit faster) and portability (port:IP is more flexible). Unix domain sockets will give you a bit better performance, while a socket connected to localhost gives you a bit better portability if you move the server app to a different OS, you can do so by just changing the IP address from localhost to a different hostname.