diff options
Diffstat (limited to 'vendor/github.com/cespare/xxhash/v2/README.md')
| -rw-r--r-- | vendor/github.com/cespare/xxhash/v2/README.md | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/vendor/github.com/cespare/xxhash/v2/README.md b/vendor/github.com/cespare/xxhash/v2/README.md new file mode 100644 index 000000000..8bf0e5b78 --- /dev/null +++ b/vendor/github.com/cespare/xxhash/v2/README.md @@ -0,0 +1,72 @@ +# xxhash + +[](https://pkg.go.dev/github.com/cespare/xxhash/v2) +[](https://github.com/cespare/xxhash/actions/workflows/test.yml) + +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 even faster +assembly implementations for amd64 and arm64. If desired, the `purego` build tag +opts into using the Go code even on those architectures. + +[xxHash]: http://cyan4973.github.io/xxHash/ + +## 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 | 1.3 GB/s | 1.2 GB/s | +| 16 B | 2.9 GB/s | 3.5 GB/s | +| 100 B | 6.9 GB/s | 8.1 GB/s | +| 4 KB | 11.7 GB/s | 16.7 GB/s | +| 10 MB | 12.0 GB/s | 17.3 GB/s | + +These numbers were generated on Ubuntu 20.04 with an Intel Xeon Platinum 8252C +CPU using the following commands under Go 1.19.2: + +``` +benchstat <(go test -tags purego -benchtime 500ms -count 15 -bench 'Sum64$') +benchstat <(go test -benchtime 500ms -count 15 -bench 'Sum64$') +``` + +## Projects using this package + +- [InfluxDB](https://github.com/influxdata/influxdb) +- [Prometheus](https://github.com/prometheus/prometheus) +- [VictoriaMetrics](https://github.com/VictoriaMetrics/VictoriaMetrics) +- [FreeCache](https://github.com/coocood/freecache) +- [FastCache](https://github.com/VictoriaMetrics/fastcache) |
