Increasing timeouts (linear or exponential) with optional jitter

backoff_time.go

package main

// Heavely based on: https://github.com/sethgrid/pester

import (
        "fmt"
        "math"
        "math/rand"
        "time"
)

func main() {
        rand.Seed(time.Now().Unix())

        for i := 0; i < 10; i++ {
                //d := linearBackoff(i)
                d := exponentialBackoff(i)
                j := jitter(d)
                fmt.Printf("%d\t %s\t %s\n", i, d, j)
        }
}

func jitter(d time.Duration) time.Duration {
        ms := int(d.Nanoseconds() / 1000000)
        maxJitter := ms / 3
        jitter := rand.Intn(maxJitter + 1)
        if rand.Intn(2) == 1 {
                ms += jitter
        } else {
                ms -= jitter
        }
        return time.Duration(ms) * time.Millisecond
}

func linearBackoff(i int) time.Duration {
        return time.Duration(i) * time.Second
}

func exponentialBackoff(i int) time.Duration {
        d := math.Pow(2, float64(i))
        return time.Duration(d) * time.Second
}

//func linearBackoffJitter(i int) time.Duration {
//return jitter(linear(i))
//}

//func exponentialBackoffJitter(i int) time.Duration {
//return jitter(exp(i))
//}