Nginx Caching with uwsgi

First sysadmin post!

I'm using Django and nginx with uwsgi for this webste. Right after the update of this site, I used PageSpeed Insights to check for the issues. It reports that my server is responding very slow(2 seconds!).

By googling around, I found that nginx has good caching support. With the use of both client cache and server cache, the rendering time of the cached pages can be reduced. Here is what I do to solve this problem:

#16m being size of cache key, 1m cache key can store 8k cache entities.
#60m being the inactivity invalidation time of cache
uwsgi_cache_path /var/www-newSite/serverCache levels=1:2 keys_zone=foo:16m inactive=60m;
server {
    ...
    # Django media
    location /media  {
        expires 1h;
        alias /var/www-newSite/media;  # your Django project's media files - amend as required
    }
    location /static {
        expires 1h;
        alias /var/www-newSite/static; # your Django project's static files - amend as required
    }
    location / {
        uwsgi_pass unix:///path/to/django_site.sock;
        include /etc/nginx/uwsgi_params;

        #client cache
        expires 5m; #Or whatever value you want

        #server cache
        uwsgi_cache foo;
        uwsgi_cache_key $uri;
        uwsgi_cache_valid any 1h; #Or whatever value you want
    }
}

You may refer to the documentation of the nginx module ngx_http_uwsgi_module for what does the directives do.

Before caching, it takes two seconds to render a page. After caching, it only take ~20 ms.

The downside of this approach is that if the database is updated, the cache isn't invalidated immediately. It probably isn't an issue for this site. In case it's a problem for you, you may want to read a bit about Django’s cache framework.