Book Image

Asynchronous Programming in Rust

By : Carl Fredrik Samson
5 (2)
Book Image

Asynchronous Programming in Rust

5 (2)
By: Carl Fredrik Samson

Overview of this book

Step into the world of asynchronous programming with confidence by conquering the challenges of unclear concepts with this hands-on guide. Using functional examples, this book simplifies the trickiest concepts, exploring goroutines, fibers, futures, and callbacks to help you navigate the vast Rust async ecosystem with ease. You’ll start by building a solid foundation in asynchronous programming and explore diverse strategies for modeling program flow. The book then guides you through concepts like epoll, coroutines, green threads, and callbacks using practical examples. The final section focuses on Rust, examining futures, generators, and the reactor-executor pattern. You’ll apply your knowledge to create your own runtime, solidifying expertise in this dynamic domain. Throughout the book, you’ll not only gain proficiency in Rust's async features but also see how Rust models asynchronous program flow. By the end of the book, you'll possess the knowledge and practical skills needed to actively contribute to the Rust async ecosystem.
Table of Contents (16 chapters)
Free Chapter
1
Part 1:Asynchronous Programming Fundamentals
5
Part 2:Event Queues and Green Threads
8
Part 3:Futures and async/await in Rust

Final thoughts

Before we round off this chapter, I want to point out that it should now be clear to us why coroutines aren’t really pre-emptable. If you remember back in Chapter 2, we said that a stackful coroutine (such as our fibers/green threads example) could be pre-empted and its execution could be paused at any point. That’s because they have a stack, and pausing a task is as simple as storing the current execution state to the stack and jumping to another task.

That’s not possible here. The only places we can stop and resume execution are at the pre-defined suspension points that we manually tagged with wait.

In theory, if you have a tightly integrated system where you control the compiler, the coroutine definition, the scheduler, and the I/O primitives, you could add additional states to the state machine and create additional points where the task could be suspended/resumed. These suspension points could be opaque to the user and treated differently...