Functional and Concurrent Programming: Core Concepts and Features

Chapter 27

Minimizing Thread Blocking

Chapter 26 advocates the functional use of futures in a programming style that minimizes thread blocking. Over the years, much effort has been spent trying to avoid unnecessary thread blocking, often for performance reasons.¹ This chapter provides a quick overview of some popular techniques that strive not to block threads and often abstain from using locks and other synchronizers.

¹This process is still ongoing. On the JVM, in particular, see https://openjdk.org/jeps/425, known as Project Loom.

27.1 Atomic Operations

As a first illustration, consider the case of class java.util.concurrent.AtomicInteger, used in some earlier examples. It is straightforward to implement a thread-safe mutable integer in Java ...