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基本介绍
常用经典哈希函数Go语言实现,提供uint32
及uint64
类型的哈希函数。
使用方式:
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import "github.com/gogf/gf/v2/encoding/ghash" |
接口文档:
...
基准测试
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goos: darwin
goarch: amd64
pkg: github.com/gogf/gf/v2/encoding/ghash
cpu: Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
Benchmark_BKDR
Benchmark_BKDR-12 39315165 26.88 ns/op
Benchmark_BKDR64
Benchmark_BKDR64-12 62891215 22.61 ns/op
Benchmark_SDBM
Benchmark_SDBM-12 49689925 25.40 ns/op
Benchmark_SDBM64
Benchmark_SDBM64-12 48860472 24.38 ns/op
Benchmark_RS
Benchmark_RS-12 39463418 25.52 ns/op
Benchmark_SRS64
Benchmark_SRS64-12 53318370 19.45 ns/op
Benchmark_JS
Benchmark_JS-12 53751033 23.20 ns/op
Benchmark_JS64
Benchmark_JS64-12 62440287 19.25 ns/op
Benchmark_PJW
Benchmark_PJW-12 42439626 27.85 ns/op
Benchmark_PJW64
Benchmark_PJW64-12 37491696 33.28 ns/op
Benchmark_ELF
Benchmark_ELF-12 38034584 31.74 ns/op
Benchmark_ELF64
Benchmark_ELF64-12 44047201 27.58 ns/op
Benchmark_DJB
Benchmark_DJB-12 46994352 22.60 ns/op
Benchmark_DJB64
Benchmark_DJB64-12 61980186 19.19 ns/op
Benchmark_AP
Benchmark_AP-12 29544234 40.58 ns/op
Benchmark_AP64
Benchmark_AP64-12 28123783 42.48 ns/op |
重复性测试
测试结果与测试内容有关联性,我这里通过uint64
数值的范围遍历来进行简单的重复性测试,仅供参考。
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package main
import (
"encoding/binary"
"fmt"
"math"
"github.com/gogf/gf/v2/encoding/ghash"
)
func main() {
var (
m = make(map[uint64]struct{})
b = make([]byte, 8)
ok bool
hash uint64
)
for i := uint64(0); i < math.MaxUint64; i++ {
binary.LittleEndian.PutUint64(b, i)
hash = ghash.PJW64(b)
if _, ok = m[hash]; ok {
fmt.Println("repeated found:", i)
break
}
m[hash] = struct{}{}
}
} |
测试结果如下:
哈希函数 | 重复位置 | 备注 |
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AP64 | 8388640 | |
BKDR64 | ||
DJB64 | ||
ELF64 | ||
JS64 | ||
PJW64 | ||
RS64 | ||
SDBM64 |
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