phusion
Document the request processing cycle
Questions like http://stackoverflow.com/questions/30842187/django-file-upload-took-forever-with-phusion-passenger makes me realize that it's useful to document the Passenger request processing cycle. People have a hard time understanding how Passenger works and what responsibilities it has, making it difficult to isolate problems to a specific component. I can tell people to increase the log level, but that doesn't help if they don't know how the request processing cycle looks like.
We should document the fact that Passenger first receives the request via Nginx, then via the Passenger core, which then forwards the request to the app, then waits for a response and forwards everything all the way back to Nginx and the client.
When you come around to document this (please do), maybe also include a section about file-uploads.
