xxhash
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.
Compatibility
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 github.com/cespare/xxhash/v2:
- 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.
Benchmarks
Here are some quick benchmarks comparing the pure-Go and assembly implementations of Sum64.
| input size | purego | asm |
|---|---|---|
| 4 B | 1052.65 MB/s | 1278.48 MB/s |
| 100 B | 6816.82 MB/s | 7881.09 MB/s |
| 4 KB | 11924.07 MB/s | 17323.63 MB/s |
| 10 MB | 11205.21 MB/s | 15484.85 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$'
go test -benchtime 10s -bench 'Sum64$'