Tokio

I recently talked at the Denver Rust Meetup about my side project to implement WebRTC data channels in Rust. I'll probably blog about this project in more detail in the future, but in the meantime here are the slides and a short demo video.

• Presentation slides (PDF, 1.7MB)
• A quick video of the demo (MP4, 5.3MB)

I also made the following informal "studio" video of the talk. The live version was probably better, but hopefully this is good enough to get the points across.

Tokio is a Rust framework for developing applications which perform asynchronous I/O — an event-driven approach that can often achieve better scalability, performance, and resource usage than conventional synchronous I/O. Unfortunately, Tokio is notoriously difficult to learn due to its sophisticated abstractions. Even after reading the tutorials, I didn't feel that I had internalized the abstractions sufficiently to be able to reason about what was actually happening.

My prior experience with asynchronous I/O programming may have even hindered my Tokio education. I'm accustomed to using the operating system's selection facility (e.g. Linux epoll) as a starting point, and then moving on to dispatch, state machines, and so forth. Starting with the Tokio abstractions with no clear insight into where and how the underlying epoll_wait() happens, I found it difficult to connect all the dots. Tokio and its future-driven approach felt like something of a black box.