High-performance general load balancing algorithm library, non-goroutine-safe.
Smooth weighted load balancing algorithm: NGINX and LVS, Doublejump provides a revamped Google's jump consistent hash.
If you want a goroutine-safe load balancer, please refer to another library, which supports more APIs: fufuok/balancer
- WeightedRoundRobin
- SmoothWeightedRoundRobin
- WeightedRand
- ConsistentHash
- RoundRobin
- Random
go get -u github.com/fufuok/load-balancerpackage main
import (
"fmt"
balancer "github.com/fufuok/load-balancer"
)
func main() {
choices := []*balancer.Choice{
{Item: "🍒", Weight: 5},
{Item: "🍋", Weight: 3},
{Item: "🍉", Weight: 1},
{Item: "🥑", Weight: 0},
}
balancer.Update(choices)
// result of smooth selection is similar to: 🍒 🍒 🍒 🍋 🍒 🍋 🍒 🍋 🍉
for i := 0; i < 9; i++ {
fmt.Print(balancer.Select(), " ")
}
fmt.Println()
}please see: examples
Sample data:
var choices []*balancer.Choice
// for WeightedRoundRobin/SmoothWeightedRoundRobin/WeightedRand
// To be selected : Weighted
wNodes := map[string]int{
"A": 5,
"B": 3,
"C": 1,
"D": 0,
}
choices = balancer.NewChoicesMap(wNodes)
// or
choices = []*balancer.Choice{
{Item: "A", Weight: 5},
{Item: "B", Weight: 3},
{Item: "C", Weight: 1},
{Item: "D", Weight: 0},
}
// for RoundRobin/Random/ConsistentHash
nodes := []string{"A", "B", "C"}
choices = balancer.NewChoicesSlice(nodes)
// or
choices = []*balancer.Choice{
{Item: "A"},
{Item: "B"},
{Item: "C"},
}-
use default balancer (WRR)
WeightedRoundRobin is the default balancer algorithm.
balancer.Update(choices)
-
use WeightedRoundRobin (WRR)
var lb balancer.Balancer lb = balancer.New(balancer.WeightedRoundRobin, choices) // or lb = balancer.New(balancer.WeightedRoundRobin, nil) lb.Update(choices) // or lb = balancer.NewWeightedRoundRobin(choices...) // or lb = balancer.NewWeightedRoundRobin() lb.Update(choices)
-
use SmoothWeightedRoundRobin (SWRR)
var lb balancer.Balancer lb = balancer.New(balancer.SmoothWeightedRoundRobin, choices) // or lb = balancer.New(balancer.SmoothWeightedRoundRobin, nil) lb.Update(choices) // or lb = balancer.NewSmoothWeightedRoundRobin(choices...) // or lb = balancer.NewSmoothWeightedRoundRobin() lb.Update(choices)
-
use WeightedRand (WR)
var lb balancer.Balancer lb = balancer.New(balancer.WeightedRand, choices) // or lb = balancer.New(balancer.WeightedRand, nil) lb.Update(choices) // or lb = balancer.NewWeightedRand(choices...) // or lb = balancer.NewWeightedRand() lb.Update(choices)
-
use ConsistentHash
var lb balancer.Balancer lb = balancer.New(balancer.ConsistentHash, choices) // or lb = balancer.New(balancer.ConsistentHash, nil) lb.Update(choices) // or lb = balancer.NewConsistentHash(choices...) // or lb = balancer.NewConsistentHash() lb.Update(choices)
-
use RoundRobin (RR)
var lb balancer.Balancer lb = balancer.New(balancer.RoundRobin, choices) // or lb = balancer.New(balancer.RoundRobin, nil) lb.Update(choices) // or lb = balancer.NewRoundRobin(choices...) // or lb = balancer.NewRoundRobin() lb.Update(choices)
-
use Random
var lb balancer.Balancer lb = balancer.New(balancer.Random, choices) // or lb = balancer.New(balancer.Random, nil) lb.Update(choices) // or lb = balancer.NewRandom(choices...) // or lb = balancer.NewRandom() lb.Update(choices)
node := lb.Select()ip consistent hash:
node := lb.Select("192.168.1.100")
node := lb.Select("192.168.1.100", "Test", "...")type Balancer interface {
// Select gets next selected item.
// key is only used for ConsistentHash
Select(key ...string) interface{}
// Name load balancer name.
Name() string
// Update reinitialize the balancer items.
Update(choices []*Choice) bool
}
// Choice to be selected for the load balancer
type Choice struct {
// e.g. server addr / node / *url.URL
Item interface{}
// For WeightedRoundRobin / SmoothWeightedRoundRobin / WeightedRand
Weight int
// For SmoothWeightedRoundRobin, optional
CurrentWeight int
}go test -run=^$ -benchmem -benchtime=1s -count=1 -bench=.
goos: linux
goarch: amd64
pkg: github.com/fufuok/load-balancer
cpu: Intel(R) Xeon(R) Gold 6151 CPU @ 3.00GHz
BenchmarkBalancer/WRR-10-4 46217316 25.75 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/SWRR-10-4 77468209 15.27 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/WR-10-4 52319631 22.49 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/Hash-10-4 39925784 30.21 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/RoundRobin-10-4 66584161 18.14 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/Random-10-4 242458752 4.904 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/WRR-100-4 40734304 30.44 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/SWRR-100-4 7942176 152.7 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/WR-100-4 31176547 38.46 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/Hash-100-4 31901799 38.02 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/RoundRobin-100-4 66206282 18.05 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/Random-100-4 244788913 4.885 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/WRR-1000-4 34538292 34.18 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/SWRR-1000-4 843820 1320 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/WR-1000-4 20156709 59.92 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/Hash-1000-4 23270704 51.25 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/RoundRobin-1000-4 66487467 18.08 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/Random-1000-4 221386104 5.098 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/WRR-10000-4 34621371 34.29 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/SWRR-10000-4 88591 14274 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/WR-10000-4 14898531 81.10 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/Hash-10000-4 19238934 62.80 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/RoundRobin-10000-4 66228592 18.31 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/Random-10000-4 191338644 6.872 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/WRR-100000-4 30867440 34.63 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/SWRR-100000-4 6897 173933 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/WR-100000-4 10732960 111.6 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/Hash-100000-4 19251387 62.78 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/RoundRobin-100000-4 65002867 18.33 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/Random-100000-4 88514517 13.07 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/WRR-1000000-4 28559396 36.27 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/SWRR-1000000-4 363 3264391 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/WR-1000000-4 4875242 238.9 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/Hash-1000000-4 19132564 62.31 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/RoundRobin-1000000-4 64232452 18.44 ns/op 0 B/op 0 allocs/op
BenchmarkBalancer/Random-1000000-4 25495011 45.96 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/WRR-10-4 18472707 67.69 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/SWRR-10-4 4228370 283.4 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/WR-10-4 208656978 6.016 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/Hash-10-4 144690333 8.001 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/RoundRobin-10-4 19509270 61.33 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/Random-10-4 919527031 1.331 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/WRR-100-4 19207489 66.60 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/SWRR-100-4 1311392 899.7 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/WR-100-4 100000000 10.26 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/Hash-100-4 120191985 9.945 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/RoundRobin-100-4 18468038 62.90 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/Random-100-4 921913453 1.324 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/WRR-1000-4 17837187 68.50 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/SWRR-1000-4 534634 2184 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/WR-1000-4 78022376 15.89 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/Hash-1000-4 87318837 13.83 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/RoundRobin-1000-4 18960835 61.85 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/Random-1000-4 214012765 5.450 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/WRR-10000-4 17449467 65.24 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/SWRR-10000-4 164738 7878 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/WR-10000-4 56703684 20.90 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/Hash-10000-4 71464341 17.37 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/RoundRobin-10000-4 19946966 59.33 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/Random-10000-4 179242167 6.321 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/WRR-100000-4 17843058 63.60 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/SWRR-100000-4 17827 66743 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/WR-100000-4 41696436 29.32 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/Hash-100000-4 71783467 16.66 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/RoundRobin-100000-4 18777990 59.97 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/Random-100000-4 130029762 9.360 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/WRR-1000000-4 12799609 78.48 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/SWRR-1000000-4 1447 853293 ns/op 1 B/op 0 allocs/op
BenchmarkBalancerParallel/WR-1000000-4 19860668 58.98 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/Hash-1000000-4 72376710 16.90 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/RoundRobin-1000000-4 19127218 62.03 ns/op 0 B/op 0 allocs/op
BenchmarkBalancerParallel/Random-1000000-4 75088678 14.43 ns/op 0 B/op 0 allocs/opThird-party library licenses:
- [doublejump](doublejump/LICENSE at master · edwingeng/doublejump (github.com))
- [go-jump](go-jump/LICENSE at master · dgryski/go-jump (github.com))
ff