Mega List of Tips for Writing Performant Go Code

Stack vs Heap Allocations

For variable with short lived scope, use non-pointer return value. For variable with long lived scope, use pointer return value. Heap allocation is expensive.

Benchmark: https://github.com/Bhupesh-V/pocs/tree/main/go/heap-escape

Buffer Pools

Use sync.Pool for frequently allocated and released objects. Buffer pool is a good example.

Benchmark: https://github.com/Bhupesh-V/pocs/tree/main/go/buffer-pool

Working with strings

Use strings.Builder in favor of bytes.Buffer for string operations.

Capping slice length

Pre-allcate memory for slices, maps if possible (when using make()).

Field Alignment in Structs

• https://go.dev/play/p/dNWspo2Dxv
• https://go.dev/play/p/0qsgpuAHHp
• https://itnext.io/structure-size-optimization-in-golang-alignment-padding-more-effective-memory-layout-linters-fffdcba27c61
• https://go101.org/article/memory-layout.html