This is a native Go implementation of the excellent xxhash* algorithm, an extremely fast non-cryptographic Hash algorithm, working at speeds close to RAM limits.
- The C implementation is (Copyright (c) 2012-2014, Yann Collet)
go get github.com/OneOfOne/xxhash
- On Go 1.7+ the pure go version is faster than CGO for all inputs.
- Supports ChecksumString{32,64} xxhash{32,64}.WriteString, which uses no copies when it can, falls back to copy on appengine.
- The native version falls back to a less optimized version on appengine due to the lack of unsafe.
- Almost as fast as the mostly pure assembly version written by the brilliant cespare, while also supporting seeds.
- To manually toggle the appengine version build with
-tags safe.
➤ go test -bench '64' -count 5 -tags cespare | benchstat /dev/stdin
name time/op
# https://github.com/cespare/xxhash
XXSum64Cespare/Func-8 160ns ± 2%
XXSum64Cespare/Struct-8 173ns ± 1%
XXSum64ShortCespare/Func-8 6.78ns ± 1%
XXSum64ShortCespare/Struct-8 19.6ns ± 2%
# this package (default mode, using unsafe)
XXSum64/Func-8 170ns ± 1%
XXSum64/Struct-8 182ns ± 1%
XXSum64Short/Func-8 13.5ns ± 3%
XXSum64Short/Struct-8 20.4ns ± 0%
# this package (appengine, *not* using unsafe)
XXSum64/Func-8 241ns ± 5%
XXSum64/Struct-8 243ns ± 6%
XXSum64Short/Func-8 15.2ns ± 2%
XXSum64Short/Struct-8 23.7ns ± 5%
CRC64ISO-8 1.23µs ± 1%
CRC64ISOString-8 2.71µs ± 4%
CRC64ISOShort-8 22.2ns ± 3%
Fnv64-8 2.34µs ± 1%
Fnv64Short-8 74.7ns ± 8% h := xxhash.New64()
// r, err := os.Open("......")
// defer f.Close()
r := strings.NewReader(F)
io.Copy(h, r)
fmt.Println("xxhash.Backend:", xxhash.Backend)
fmt.Println("File checksum:", h.Sum64())- Rewrite the 32bit version to be more optimized.
- General cleanup as the Go inliner gets smarter.
This project is released under the Apache v2. license. See LICENSE for more details.
