futures-rs is the library which will hopefully become a shared foundation for everything async in Rust. However it's already become renowned for having a steep learning curve, even for experienced Rustaceans.

I think one of the best ways to get comfortable with using a library is to look at how it works internally: often API design can seem bizarre or impenetrable and it's only when you put yourself in the shoes of the library author that you can really understand why it was designed that way.

In this post I'll try to put down on "paper" my understanding of how futures work and I'll aim to do it in a visual way. I'm going to assume you're already somewhat familiar with Rust and why futures are a useful tool to have at one's disposal.

For most of this post I'll be talking about how things work today (as of September 2017). At the end I'll touch on what's being proposed next and also make a case for some of the changes I'd like to see.

If you're interested in learning more ab

This guide uses the domain your-domain.tld and its www. prefixed version. It starts the rocket application on 127.0.0.1:1337 and as the user www-data. The proxy listens on port 80 and 443 though.
If you need other values, update them accordingly in your nginx and systemd configs.

You need to have nginx, certbot and rust installed.

Some notes about:

• Explaining why current day Linux memory swap thrashing still happens (as of 2016).
• Mitigating "stop the world" type thrashing issues on a Linux workstation when it's under high memory pressure and where responsiveness is more important than process completion.
• Prioritizing and limiting memory use.
• Older ulimit versus newer CGroup options.

These notes assume some basic background knowledge about memory management, ulimits and cgroups.