Maglev: A Google Maglev Hashing Algorithm implement in Golang

What is Maglev

Maglev is Google’s network load balancer. It is a large distributed software system that runs on commodity Linux servers. Unlike traditional hardware network load balancers, it does not require a specialized physical rack deployment, and its capacity can be easily adjusted by adding or removing servers. (cite from paper)

Here is a Chinese reading note about Maglev: [論文中文導讀] Maglev : A Fast and Reliable Software Network Load Balancer (using Consistent Hashing)

Installation and Usage

Install

go get github.com/kkdai/maglev

Usage

func main() {
	sizeN := 5
	lookupSizeM := 13 //(must be prime number)

	var names []string
	for i := 0; i < sizeN; i++ {
		names = append(names, fmt.Sprintf("backend-%d", i))
	}
	//backend-0 ~ backend-4

	mm, err := NewMaglev(names, lookupSizeM)
	if err != nil {
		log.Fatal("NewMaglev failed:", err)
	}
	v, err := mm.Get("IP1")
	fmt.Println("node1:", v)
	//node1: backend-2
	v, _ = mm.Get("IP2")
	log.Println("node2:", v)
	//node2: backend-1
	v, _ = mm.Get("IPasdasdwni2")
	log.Println("node3:", v)
	//node3: backend-0

	if err := mm.Remove("backend-0"); err != nil {
		log.Fatal("Remove failed", err)
	}
	v, _ = mm.Get("IPasdasdwni2")
	log.Println("node3-D:", v)
	//node3-D: Change from "backend-0" to "backend-1"
}

Inspired By

• Wiki Consistent_hashing
• Go implementation of maglev hashing
• 每天进步一点点——五分钟理解一致性哈希算法(consistent hashing)
• Distributed Systems Part-1: A peek into consistent hashing!

Project52

It is one of my project 52.

License

This is under the Apache 2.0 license. See the LICENSE file for details.