From 51975eae037c63ad0b87a06daa8d413e5d12b32d Mon Sep 17 00:00:00 2001
From: joyyizhang <joyyizhang@tencent.com>
Date: Sat, 21 Dec 2019 21:32:02 +0800
Subject: [PATCH] fast init

---
 .gitignore       |  5 +++++
 go.mod           |  5 +++++
 go.sum           | 13 +++++++++++++
 hashring.go      |  9 +++++++--
 hashring_test.go | 36 ++++++++++++++++++++++++++++++++++--
 5 files changed, 64 insertions(+), 4 deletions(-)
 create mode 100644 .gitignore
 create mode 100644 go.mod
 create mode 100644 go.sum

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..c88aff0
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,5 @@
+.idea
+*.exe
+demo
+etc/*.conf
+etc/*.cfg
\ No newline at end of file
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..76a0b56
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,5 @@
+module github.com/joykk/hashring
+
+go 1.13
+
+require github.com/sirupsen/logrus v1.4.2
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..706fe8d
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,13 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/konsorten/go-windows-terminal-sequences v1.0.1 h1:mweAR1A6xJ3oS2pRaGiHgQ4OO8tzTaLawm8vnODuwDk=
+github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/sirupsen/logrus v1.4.2 h1:SPIRibHv4MatM3XXNO2BJeFLZwZ2LvZgfQ5+UNI2im4=
+github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6MwdIuYE2rE=
+github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
+github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+golang.org/x/sys v0.0.0-20190422165155-953cdadca894 h1:Cz4ceDQGXuKRnVBDTS23GTn/pU5OE2C0WrNTOYK1Uuc=
+golang.org/x/sys v0.0.0-20190422165155-953cdadca894/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
diff --git a/hashring.go b/hashring.go
index 4ac0ffd..d6d22a9 100644
--- a/hashring.go
+++ b/hashring.go
@@ -88,8 +88,12 @@ func (h *HashRing) generate() {
 	}
 
 	totalVirtualSpots := h.virualSpots * len(h.weights)
-	h.nodes = nodesArray{}
 
+	var nodeLen, nodeIndex int64
+	for _, w := range h.weights {
+		nodeLen += int64(math.Floor(float64(w) / float64(totalW) * float64(totalVirtualSpots)))
+	}
+	h.nodes = make(nodesArray, nodeLen)
 	for nodeKey, w := range h.weights {
 		spots := int(math.Floor(float64(w) / float64(totalW) * float64(totalVirtualSpots)))
 		for i := 1; i <= spots; i++ {
@@ -100,7 +104,8 @@ func (h *HashRing) generate() {
 				nodeKey:   nodeKey,
 				spotValue: genValue(hashBytes[6:10]),
 			}
-			h.nodes = append(h.nodes, n)
+			h.nodes[nodeIndex] = n
+			nodeIndex += 1
 			hash.Reset()
 		}
 	}
diff --git a/hashring_test.go b/hashring_test.go
index c92fdfc..5c919a0 100644
--- a/hashring_test.go
+++ b/hashring_test.go
@@ -1,8 +1,12 @@
 package hashring
 
 import (
-	//	"fmt"
+	"fmt"
+	"regexp"
+	"runtime"
+	"strconv"
 	"testing"
+	"time"
 )
 
 const (
@@ -22,7 +26,6 @@ func getNodesCount(nodes nodesArray) (int, int, int) {
 		}
 		if node.nodeKey == node2 {
 			node2Count += 1
-
 		}
 		if node.nodeKey == node3 {
 			node3Count += 1
@@ -82,3 +85,32 @@ func TestHash(t *testing.T) {
 	t.Logf("len of nodes is %v after AddNode node1:%v, node2:%v, node3:%v", len(hash.nodes), c1, c2, c3)
 
 }
+
+func TimeTrack(start time.Time) {
+	elapsed := time.Since(start)
+
+	// Skip this function, and fetch the PC and file for its parent.
+	pc, _, _, _ := runtime.Caller(1)
+
+	// Retrieve a function object this functions parent.
+	funcObj := runtime.FuncForPC(pc)
+
+	// Regex to extract just the function name (and not the module path).
+	runtimeFunc := regexp.MustCompile(`^.*\.(.*)$`)
+	name := runtimeFunc.ReplaceAllString(funcObj.Name(), "$1")
+
+	fmt.Printf("TimeTrack funcName:%s elapsed:%s \n", name, elapsed)
+}
+
+func TestSpeed(t *testing.T) {
+	// node=1000 v=50000 on 16GB/win10/i7 init 35s
+	defer TimeTrack(time.Now())
+	nodeWeight := make(map[string]int)
+	for i := 0; i < 1000; i += 1 {
+		nodeWeight[strconv.Itoa(i)] = 1
+	}
+	vitualSpots := 50000
+	hash := NewHashRing(vitualSpots)
+
+	hash.AddNodes(nodeWeight)
+}