Part 20. Performance and Optimization

Performance is one of the main reasons people choose Zig.

10 items

Section	Title
1	What Actually Makes Programs Slow?
2	Why Profiling Matters
3	The Basic Idea
4	Why SIMD Matters
5	Why Allocations Cost Time
6	Small Values Are Fine to Copy
7	Why Branch Prediction Exists
8	Benchmark the Right Thing
9	The Basic Idea
10	Case Study 1: Reusing a Temporary Buffer

Writes › Book › Zig › Part 20. Performance and Optimization ›

What Actually Makes Programs Slow?

Performance is one of the main reasons people choose Zig.

Writes › Book › Zig › Part 20. Performance and Optimization ›

Why Profiling Matters

When a program feels slow, your first job is not optimization.

Writes › Book › Zig › Part 20. Performance and Optimization ›

The Basic Idea

Modern CPUs are fast, but memory is much slower.

Writes › Book › Zig › Part 20. Performance and Optimization ›

Why SIMD Matters

SIMD means Single Instruction, Multiple Data.

Writes › Book › Zig › Part 20. Performance and Optimization ›

Why Allocations Cost Time

Allocations are one of the most common causes of slow programs.

Writes › Book › Zig › Part 20. Performance and Optimization ›

Small Values Are Fine to Copy

Copying data is sometimes necessary, but unnecessary copying is one of the easiest ways to waste time and memory.

Writes › Book › Zig › Part 20. Performance and Optimization ›

Why Branch Prediction Exists

Branch prediction is a CPU optimization.

Writes › Book › Zig › Part 20. Performance and Optimization ›

Benchmark the Right Thing

Benchmarking means measuring how fast code runs.

Writes › Book › Zig › Part 20. Performance and Optimization ›

The Basic Idea

An abstraction is a way to hide detail behind a simpler interface.

Writes › Book › Zig › Part 20. Performance and Optimization ›

Case Study 1: Reusing a Temporary Buffer

Performance ideas become clearer when you see them inside real code.