add some Benchmarking function

Author: CC11001100

benchmarking.go

@@ -0,0 +1,27 @@
+package varint
+
+import (
+	"github.com/golang-infrastructure/go-gtypes"
+	"unsafe"
+)
+
+// 这个文件中存放的是一些计算压缩率相关的方法
+
+// BenchmarkingValueRatio 计算单个值的压缩率
+func BenchmarkingValueRatio[T gtypes.Unsigned](value T) float64 {
+	rawByteSize := unsafe.Sizeof(value)
+	varintBytes := Encode(value)
+	return float64(len(varintBytes)) * 100 / float64(rawByteSize)
+}
+
+// BenchmarkingValueSliceRatio 计算整个切片的压缩率
+func BenchmarkingValueSliceRatio[T gtypes.Unsigned](valueSlice []T) float64 {
+	rawByteSizeSum := uint64(0)
+	varintBytesSum := uint64(0)
+	for _, v := range valueSlice {
+		bytes := Encode(v)
+		varintBytesSum += uint64(len(bytes))
+		rawByteSizeSum += uint64(unsafe.Sizeof(v))
+	}
+	return float64(varintBytesSum) * 100 / float64(rawByteSizeSum)
+}

benchmarking_test.go

@@ -0,0 +1,29 @@
+package varint
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestBenchmarkingValueRatio(t *testing.T) {
+
+	{
+		value := uint64(1)
+		ratio := BenchmarkingValueRatio(value)
+		assert.Equal(t, 12.5, ratio)
+	}
+
+}
+
+func TestBenchmarkingValueSliceRatio(t *testing.T) {
+
+	{
+		// 12.5% 是上限，如果出现了较大的值压缩率只会比这个低不会比这个高
+		values := []uint64{
+			1, 2, 3, 4, 5, 999999,
+		}
+		ratio := BenchmarkingValueSliceRatio(values)
+		assert.Equal(t, 16.666666666666668, ratio)
+	}
+
+}