Book Image

Hands-On Concurrency with Rust

By : Brian L. Troutwine
Book Image

Hands-On Concurrency with Rust

By: Brian L. Troutwine

Overview of this book

Most programming languages can really complicate things, especially with regard to unsafe memory access. The burden on you, the programmer, lies across two domains: understanding the modern machine and your language's pain-points. This book will teach you to how to manage program performance on modern machines and build fast, memory-safe, and concurrent software in Rust. It starts with the fundamentals of Rust and discusses machine architecture concepts. You will be taken through ways to measure and improve the performance of Rust code systematically and how to write collections with confidence. You will learn about the Sync and Send traits applied to threads, and coordinate thread execution with locks, atomic primitives, data-parallelism, and more. The book will show you how to efficiently embed Rust in C++ code and explore the functionalities of various crates for multithreaded applications. It explores implementations in depth. You will know how a mutex works and build several yourself. You will master radically different approaches that exist in the ecosystem for structuring and managing high-scale systems. By the end of the book, you will feel comfortable with designing safe, consistent, parallel, and high-performance applications in Rust.
Table of Contents (18 chapters)
Title Page
Copyright and Credits
Packt Upsell

Chapter 7. Atomics – Safely Reclaiming Memory

In the previous chapter, we discussed the atomic primitives available to the Rust programmer, implementing higher-level synchronization primitives and some data structures built entirely of atomics. A key challenge with atomic-only programming, compared to using higher-level synchronization primitives, is memory reclamation. It is only safe to free memory once. When we build concurrent algorithms only from atomic primitives, it's very challenging to do something only once and keep performance up. That is, safely reclaiming memory requires some form of synchronization. But, as the total number of concurrent actors rise, the cost of synchronization dwarfs the latency or throughput benefits of atomic programming.

In this chapter, we will discuss three techniques to resolve the memory reclamation issue of atomic programming—reference counting, hazard pointers, and epoch-based reclamation. These methods will be familiar to you from previous chapters...