Job Ready Go

Lesson 18Concurrency

In this lesson, we'll look at the concept of concurrency and show you how to apply it to your Go applications. We'll spend extra time explaining concurrency concepts and parallelism before writing Go code.

LEARNING OBJECTIVES

By the end of this lesson, you will be able to:

• Understand concurrency and some of its challenges.
• Understand parallelism and some of its challenges.
• Use goroutines.
• Work with channels.
• Iterate through channels.

USING CONCURRENCY

Before we go into details about how Go handles concurrency, let's look at the concept of concurrency itself. In the early days of computing, a computer system had one processor that was responsible for executing all instructions. Because of this architecture, computer programs were written to run in a serial fashion, where the program was sequentially executed instruction by instruction in a predefined order. Figure 18.1 illustrates this use of serial programming by a computer program.

Figure 18.1: Serial programming

As computer programs became increasingly complex, the use of serial programming introduced some limitations because a program could only execute one instruction at a time. The more instructions a computer program had, the longer it would take to execute. This resulted in the need for faster and more efficient ways to execute computer programs.

The Role of the Operating System