Large file download from self hosted website
thank you very much for your feedback, it was very helpful for me to be able to ask around the right questions and find an answer.
It turns out, our nginx server was simply forwarding the requests from the public address to the local address in our server; the app was then actually using a Tornado web server. So the solution was simply to use nginx directly to serve the static files, and only forwarding to the tornado server for the non-static part. This solved the memory problem.
Thank you again for the help and for putting up with my beginner questions :)