From a5fb792dcf0ccf852493aea88125c4fba15125c6 Mon Sep 17 00:00:00 2001
From: charlie <3140647@qq.com>
Date: Mon, 28 Mar 2022 17:35:58 +0800
Subject: [PATCH] fnv

---
 collections/generics/concurrent_map.go      | 46 +++++++++--
 collections/generics/concurrent_map_test.go | 85 +++++++++++++++++++++
 collections/generics/map_test.go            | 28 +++++++
 collections/generics/rwlock_map.go          | 11 +--
 4 files changed, 158 insertions(+), 12 deletions(-)

diff --git a/collections/generics/concurrent_map.go b/collections/generics/concurrent_map.go
index 3e1982d..a848c6a 100644
--- a/collections/generics/concurrent_map.go
+++ b/collections/generics/concurrent_map.go
@@ -4,8 +4,6 @@ import (
 	"fmt"
 	"runtime"
 	"sync"
-
-	"github.com/charlienet/go-mixed/hash"
 )
 
 var _ Map[string, string] = &ConcurrnetMap[string, string]{}
@@ -91,12 +89,46 @@ func (m *ConcurrnetMap[K, V]) Count() int {
 }
 
 func (m *ConcurrnetMap[K, V]) getBucket(k K) Map[K, V] {
-	bytes := getBytes(k)
-
-	id := hash.XXHashUint64(bytes) % m.numOfBuckets
+	id := getTag(k) % m.numOfBuckets
 	return m.buckets[id]
 }
 
-func getBytes(k any) []byte {
-	return []byte(fmt.Sprintf("%v", k))
+func getTag[T comparable](v T) uint64 {
+	var vv any = v
+
+	switch vv.(type) {
+	case string:
+		return fnv64(vv.(string))
+	case int8:
+		return uint64(vv.(int8))
+	case uint8:
+		return uint64(vv.(uint8))
+	case int:
+		return uint64(vv.(int))
+	case int32:
+		return uint64(vv.(int32))
+	case uint32:
+		return uint64(vv.(uint32))
+	case int64:
+		return uint64(vv.(int64))
+	case uint64:
+		return vv.(uint64)
+	default:
+		return fnv64(fmt.Sprintf("%v", v))
+	}
+}
+
+const (
+	prime32 = uint64(16777619)
+)
+
+func fnv64(k string) uint64 {
+	var hash = uint64(2166136261)
+	l := len(k)
+	for i := 0; i < l; i++ {
+		hash *= prime32
+		hash ^= uint64(k[i])
+	}
+
+	return hash
 }
diff --git a/collections/generics/concurrent_map_test.go b/collections/generics/concurrent_map_test.go
index 3b4aa97..6d46495 100644
--- a/collections/generics/concurrent_map_test.go
+++ b/collections/generics/concurrent_map_test.go
@@ -5,7 +5,9 @@ import (
 	"runtime"
 	"testing"
 
+	"github.com/charlienet/go-mixed/bytesconv"
 	"github.com/charlienet/go-mixed/collections/generics"
+	"github.com/charlienet/go-mixed/hash"
 )
 
 func TestConcurrentMap(t *testing.T) {
@@ -81,3 +83,86 @@ func BenchmarkRWLockMap(b *testing.B) {
 		}
 	})
 }
+
+func BenchmarkGetIndex(b *testing.B) {
+
+	b.Run("字符串-Sprintf", func(b *testing.B) {
+		v := "abc"
+		for i := 0; i < b.N; i++ {
+			bytes := []byte(fmt.Sprintf("%v", v))
+			hash.XXHashUint64(bytes)
+		}
+	})
+
+	b.Run("字符串", func(b *testing.B) {
+		v := "abc"
+		for i := 0; i < b.N; i++ {
+			getTag(v)
+		}
+	})
+
+	b.Run("数字", func(b *testing.B) {
+		v := 124
+		for i := 0; i < b.N; i++ {
+			getTag(v)
+		}
+	})
+}
+
+func getTag[T comparable](v T) uint64 {
+	var vv any = v
+
+	switch vv.(type) {
+	case string:
+		return getStringIndex([]byte(vv.(string)))
+	case int8:
+		return uint64(vv.(int8))
+	case uint8:
+		return uint64(vv.(uint8))
+	case int:
+		return uint64(vv.(int))
+	case int32:
+		return uint64(vv.(int32))
+	case uint32:
+		return uint64(vv.(uint32))
+	case int64:
+		return uint64(vv.(int64))
+	case uint64:
+		return vv.(uint64)
+	default:
+		return getStringIndex([]byte(fmt.Sprintf("%v", v)))
+	}
+}
+
+func getStringIndex(v []byte) uint64 {
+	if len(v) > 4 {
+		v = v[:4]
+	}
+
+	// return hash.XXHashUint64(v)
+	i, _ := bytesconv.BigEndian.BytesToUInt64(v)
+	return i
+}
+
+func TestFnv64(t *testing.T) {
+	t.Log(fnv64("a"))
+	t.Log(fnv64("b"))
+	t.Log(fnv64("c"))
+	t.Log(fnv64("d"))
+	t.Log(fnv64("e"))
+}
+
+const (
+	prime32 = uint64(16777619)
+)
+
+func fnv64(k string) uint64 {
+	var hash = uint64(2166136261)
+	l := len(k)
+	for i := 0; i < l; i++ {
+		hash *= prime32
+		hash ^= uint64(k[i])
+	}
+
+	return hash
+}
diff --git a/collections/generics/map_test.go b/collections/generics/map_test.go
index 371287a..047ef81 100644
--- a/collections/generics/map_test.go
+++ b/collections/generics/map_test.go
@@ -29,3 +29,31 @@ func TestMapCount(t *testing.T) {
 	mm["a"] = "b"
 	assert.Equal(t, 1, len(mm))
 }
+
+func BenchmarkMap(b *testing.B) {
+	b.Run("RWLock", func(b *testing.B) {
+		m := generics.NewRWLockMap[string, string]()
+		doBenchamark(b, m)
+
+	})
+
+	b.Run("ConcurrnetMap", func(b *testing.B) {
+		doBenchamark(b, generics.NewConcurrnetMap[string, string]())
+	})
+}
+
+func doBenchamark(b *testing.B, m generics.Map[string, string]) {
+	var k = "abc"
+	var v = "bcd"
+
+	b.RunParallel(func(p *testing.PB) {
+		for p.Next() {
+			m.Set(k, v)
+			m.Get(k)
+			m.Get(k)
+			m.Get(k)
+			m.Delete(k)
+		}
+	})
+
+}
diff --git a/collections/generics/rwlock_map.go b/collections/generics/rwlock_map.go
index 119157d..cd7aaab 100644
--- a/collections/generics/rwlock_map.go
+++ b/collections/generics/rwlock_map.go
@@ -1,6 +1,10 @@
 package generics
 
-import "sync"
+import (
+	"sync"
+
+	"golang.org/x/exp/maps"
+)
 
 var _ Map[string, string] = &RWLockMap[string, string]{}
 
@@ -41,10 +45,7 @@ func (m *RWLockMap[K, V]) ForEach(f func(K, V)) {
 }
 
 func (m *RWLockMap[K, V]) Clone() Map[K, V] {
-	new := make(map[K]V, m.Count())
-	for k, v := range m.m {
-		new[k] = v
-	}
+	new := maps.Clone(m.m)
 
 	return &RWLockMap[K, V]{
 		m: new,