Benchmark murmur3(32) and xxHash64

hash_test.go

package main_test

import (
	"strconv"
	"testing"

	"github.com/cespare/xxhash"
	"github.com/spaolacci/murmur3"
)

func BenchmarkMurmur3(b *testing.B) {
	buf := make([]byte, 8192)
	for length := 1; length <= cap(buf); length *= 2 {
		b.Run(strconv.Itoa(length), func(b *testing.B) {
			buf = buf[:length]
			b.SetBytes(int64(length))
			b.ReportAllocs()
			b.ResetTimer()
			for i := 0; i < b.N; i++ {
				murmur3.Sum32(buf)
			}
		})
	}
}

func BenchmarkXXHash64(b *testing.B) {
	buf := make([]byte, 8192)
	d := xxhash.New()
	for length := 1; length <= cap(buf); length *= 2 {
		b.Run(strconv.Itoa(length), func(b *testing.B) {
			buf = buf[:length]
			b.SetBytes(int64(length))
			b.ReportAllocs()
			b.ResetTimer()
			for i := 0; i < b.N; i++ {
				d.Write(buf)
				d.Sum64()
			}
		})
	}
}

//results
```
Running tool: /usr/local/go/bin/go test -benchmem -run=^$ -bench ^(BenchmarkMurmur3)$

goos: darwin
goarch: amd64
BenchmarkMurmur3/1-8 	261194529	         4.65 ns/op	 215.26 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/2-8 	231687916	         5.16 ns/op	 387.90 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/4-8 	244568409	         5.10 ns/op	 784.66 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/8-8 	202498562	         6.18 ns/op	1294.40 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/16-8         	155917936	         7.89 ns/op	2027.11 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/32-8         	100000000	        12.1 ns/op	2637.71 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/64-8         	61134163	        19.9 ns/op	3220.25 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/128-8        	35080591	        35.0 ns/op	3657.05 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/256-8        	16728124	        69.4 ns/op	3691.12 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/512-8        	 8880228	       141 ns/op	3639.67 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/1024-8       	 4368697	       301 ns/op	3400.01 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/2048-8       	 2092203	       543 ns/op	3771.25 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/4096-8       	 1090856	      1060 ns/op	3865.08 MB/s	       0 B/op	       0 allocs/op
BenchmarkMurmur3/8192-8       	  574178	      2254 ns/op	3634.05 MB/s	       0 B/op	       0 allocs/op
PASS

Running tool: /usr/local/go/bin/go test -benchmem -run=^$ -bench ^(BenchmarkXXHash64)$

goos: darwin
goarch: amd64
BenchmarkXXHash64/1-8 	76161969	        14.2 ns/op	  70.43 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/2-8 	81727155	        14.4 ns/op	 139.15 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/4-8 	70088184	        17.1 ns/op	 233.93 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/8-8 	63670485	        17.5 ns/op	 458.18 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/16-8         	55560175	        20.2 ns/op	 790.71 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/32-8         	47499522	        24.8 ns/op	1288.36 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/64-8         	38354180	        29.7 ns/op	2151.46 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/128-8        	35680100	        32.6 ns/op	3923.77 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/256-8        	28122490	        42.5 ns/op	6028.58 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/512-8        	22367116	        55.1 ns/op	9289.50 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/1024-8       	13504466	        86.0 ns/op	11909.89 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/2048-8       	 8672275	       143 ns/op	14356.78 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/4096-8       	 4205932	       263 ns/op	15554.23 MB/s	       0 B/op	       0 allocs/op
BenchmarkXXHash64/8192-8       	 2297762	       502 ns/op	16325.62 MB/s	       0 B/op	       0 allocs/op
PASS
```