Function ExponentialBackoff

rivershared/util/serviceutil/service_util.go:66–73

ExponentialBackoff returns a duration for a reasonable exponential backoff interval for a service based on the given attempt number, which can then be fed into CancellableSleep to perform the sleep. Uses a 2**N second algorithm, +/- 10% random jitter. Sleep is cancelled if the given context is cance

(attempt, maxAttemptsBeforeReset int)

// - 32s
// - 64s.
func ExponentialBackoff(attempt, maxAttemptsBeforeReset int) time.Duration {
	retrySeconds := exponentialBackoffSecondsWithoutJitter(attempt, maxAttemptsBeforeReset)

	// Jitter number of seconds +/- 10%.
	retrySeconds += retrySeconds * (rand.Float64()*0.2 - 0.1)

	return timeutil.SecondsAsDuration(retrySeconds)
}

func exponentialBackoffSecondsWithoutJitter(attempt, maxAttemptsBeforeReset int) float64 {
	// It's easier for callers and more intuitive if attempt starts at one, but