The fork-join pattern is a structured way to parallelize work: you fork a large task into smaller independent subtasks, run them concurrently, and then join their results to produce the final answer. It is one of the most effective patterns for CPU-bound workloads because it maps naturally to multi-core execution and supports divide-and-conquer algorithms.

In this chapter, we'll explore how fork-join works, understand work stealing in depth, and implement recursive parallel algorithms correctly.

What is Fork-Join?