Three new books, Go Optimizations 101, Go Details & Tips 101 and Go Generics 101 are published now. It is most cost-effective to buy all of them through this book bundle in the Leanpub book store.

About Go Optimizations 101

This book offers practical tricks, tips, and suggestions to optimize Go code performance. Its insights are grounded in the official Go compiler and runtime implementation.

Life is full of trade-offs, and so is the programming world. In programming, we constantly balance trade-offs between code readability, maintainability, development efficiency, and performance, and even within each of these areas. For example, optimizing for performance often involves trade-offs between memory savings, execution speed, and implementation complexity.

In real-world projects, most code sections don't demand peak performance. Prioritizing maintainability and readability generally outweighs shaving every byte or microsecond. This book focuses on optimizing critical sections where performance truly matters. Be aware that some suggestions might lead to more verbose code or only exhibit significant gains in specific scenarios.

The contents in this book include:

how to consume less CPU resources.
how to consume less memory.
how to make less memory allocations.
how to control memory allocation places.
how to reduce garbage collection pressure.

This book neither explains how to use performance analysis tools, such as pprof, nor tries to study deeply on compiler and runtime implementation details. The books also doesn't introduce how to use profile-guided optimization. None of the contents provided in this book make use of unsafe pointers and cgo. And the book doesn't talk about algorithms. In other words, this book tries to provide some optimization suggestions in a way which is clear and easy to understand, for daily general Go programming.

Without particularly indicated, the code examples provided in this book are tested and run on a notebook with the following environment setup:

go version go1.24rc1 linux/amd64
goos: linux
goarch: amd64
cpu: Intel(R) Core(TM) i5-4210U CPU @ 1.70GHz

Some benchmark times information is removed from benchmark results, to keep benchmark lines short.

Please note that:

some of the talked suggestions in this book work on any platform and for any CPU models, but some others might only work on specified platforms and for specified CPU models. So please benchmark them on the same environments as your production environments before adopting any of them.
some implementation details of the official standard Go compiler and runtime might change from version to version, which means some of the talked suggestions might not work for future Go toolchain versions.
the book will be open sourced eventually, in a chapter by chapter way.

About the author

Tapir is the author of this book. He also wrote the Go 101 book. He is planning to write some other Go 101 series books. Please look forward to.

Tapir was ever (maybe will be again) an indie game developer. You can find his games here: tapirgames.com.

About GoTV

During writing this book, the tool GoTV is used to manage installations of multiple Go toolchain versions and check the behavior differences between Go toolchain versions.

Feedback

Welcome to improve this book by submitting corrections to Go 101 issue list (https://github.com/go101/go101) for all kinds of mistakes, such as typos, grammar errors, wording inaccuracies, wrong explanations, description flaws, code bugs, etc.

It is also welcome to send your feedback to the Go 101 twitter account: @zigo_101 (https://twitter.com/zigo_101).

(more articles ↡)

The Go 101 project is hosted on Github. Welcome to improve Go 101 articles by submitting corrections for all kinds of mistakes, such as typos, grammar errors, wording inaccuracies, description flaws, code bugs and broken links.

If you would like to learn some Go details and facts every serveral days, please follow Go 101's official Twitter account @zigo_101.

The digital versions of this book are available at the following places:

Leanpub store, $7.99+ (Or buy this book from this or this book bundle).
Apple Books store, $7.99.
Amazon Kindle store, $7.99.

Tapir, the author of Go 101, has been on writing the Go 101 series books and maintaining the go101.org website since 2016 July. New contents will be continually added to the book and the website from time to time. Tapir is also an indie game developer. You can also support Go 101 by playing Tapir's games (made for both Android and iPhone/iPad):

Color Infection (★★★★★), a physics based original casual puzzle game. 140+ levels.
Rectangle Pushers (★★★★★), an original casual puzzle game. Two modes, 104+ levels.
Let's Play With Particles, a casual action original game. Three mini games are included.

Individual donations via PayPal are also welcome.

Articles in this book:

Acknowledgments
About Go Optimizations 101
Value Parts and Value Sizes ^{(available in the paid ebooks)}

value/type sizes
memory alignments
struct padding
avoid larger copy costs

Memory Allocations
Stack and Escape Analysis ^{(available in the paid ebooks)}

escape analysis
how to control value allocation places
stacks growth and shrinkage
how to reduce stack grow times

Garbage Collection ^{(available in the paid ebooks)}

GC pacer
how to reduce GC pressure
control GC frequency

Pointers
Structs ^{(available in the paid ebooks)}

3 facts/suggestions

Arrays and Slices ^{(available in the paid ebooks)}

10+ facts/suggestions

String and Byte Slices ^{(available in the paid ebooks)}

10+ facts/suggestions

BCE (Bound Check Elimination)

the cases BCE works for
the cases BCE doesn't work for
the cases BCE works for when given hints

Maps
Channels ^{(available in the paid ebooks)}

3 facts/suggestions

Functions ^{(available in the paid ebooks)}

how to make a function inline-able
how to make a function not inline-able
pointer parameters/results vs. non-pointer ones
named results vs. anonymous ones
10+ facts/suggestions

Interfaces ^{(available in the paid ebooks)}

value boxing costs
3+ facts/suggestions