Hello! I'm Vlad and today I want to explore the topic of concurrency in Go and try to practically examine different goroutine synchronization primitives.

Developing multithreaded programs has always been a challenging task that requires a deep understanding of synchronization mechanisms. As for Go, it provides developers with a powerful set of tools for working with concurrency. Synchronization primitives in Go are key components for creating reliable and efficient concurrent programs.

In this article, we'll look at the main synchronization primitives that Go offers and their practical applications. Understanding these tools is critical for every Gopher as they help avoid typical concurrent programming problems and write more reliable code.

Concurrency in Go

Concurrency and parallelism are two different concepts that are often confused.

Concurrency

Concurrency is the ability of a program to handle multiple tasks simultaneously, regardless of whether they are executed in parallel or not. In Go, this is achieved through goroutines - lightweight execution threads (from 2KB) managed by the Go Scheduler.

To explain it briefly and simply - the Go scheduler very quickly (seemingly almost simultaneously) switches contexts between goroutines, ensuring their concurrent execution.

Main characteristics of concurrency in Go:

• Goroutines can execute independently of each other
• The Go scheduler decides when and how to allocate resources between goroutines

Parallelism

Parallelism is the simultaneous execution of multiple tasks on different processors or cores. It's a subset of concurrency that is only possible on systems with multiple processors.

Key differences:

• Parallelism requires multiple processors or cores
• Parallelism is about simultaneous execution
• Not all concurrent programs are necessarily parallel

As Rob Pike said:

Concurrency is about dealing with lots of things at once.

Parallelism is about doing lots of things at once.