Clone this repo:
  1. aa1a74e Add 16-byte hash benchmarks by Caleb Spare · 5 months ago main
  2. 9ee41ed Switch to WillAbides/setup-go-faster by Caleb Spare · 9 months ago setup-go-faster
  3. 532df6a Format with Go 1.17 gofmt to use //go:build constraints by Caleb Spare · 9 months ago
  4. 08b98dc Make comment more accurate by Caleb Spare · 9 months ago
  5. 0f9df28 Run tests on 386, arm, and arm64 via qemu by Caleb Spare · 9 months ago qemu-arm64


Go Reference Test

xxhash is a Go implementation of the 64-bit xxHash algorithm, XXH64. This is a high-quality hashing algorithm that is much faster than anything in the Go standard library.

This package provides a straightforward API:

func Sum64(b []byte) uint64
func Sum64String(s string) uint64
type Digest struct{ ... }
    func New() *Digest

The Digest type implements hash.Hash64. Its key methods are:

func (*Digest) Write([]byte) (int, error)
func (*Digest) WriteString(string) (int, error)
func (*Digest) Sum64() uint64

The package is written with optimized pure Go and also contains an even faster assembly implementation for amd64. If desired, the purego build tag opts into using the Go code even on amd64.


This package is in a module and the latest code is in version 2 of the module. You need a version of Go with at least “minimal module compatibility” to use

  • 1.9.7+ for Go 1.9
  • 1.10.3+ for Go 1.10
  • Go 1.11 or later

I recommend using the latest release of Go.


Here are some quick benchmarks comparing the pure-Go and assembly implementations of Sum64.

input sizepuregoasm
4 B1052.65 MB/s1278.48 MB/s
100 B6816.82 MB/s7881.09 MB/s
4 KB11924.07 MB/s17323.63 MB/s
10 MB11205.21 MB/s15484.85 MB/s

These numbers were generated on Ubuntu 18.04 with an Intel i7-8700K CPU using the following commands under Go 1.17:

go test -tags purego -benchtime 10s -bench 'Sum64$'
go test -benchtime 10s -bench 'Sum64$'

Projects using this package