exponential_backoff

Documentation

Index

• Constants
• Variables
• func CalculateDelay(initialDelay time.Duration, retryCount int) time.Duration
• func CalculateDelayWithMax(initialDelay time.Duration, maxDelay time.Duration, retryCount int) time.Duration

Constants

const ExponentialDelayFactor float64 = 2.0 // Each delta delay is twice bigger.

const ExponentialDelayRandomMs = 1000 // Each delay has random additional milliseconds.

const MaxExponentialBackoffDelay = time.Duration(32 * time.Second)

Variables

var ExponentialCalculationsCount = int(math.Log(MaxExponentialBackoffDelay.Seconds()) / math.Log(ExponentialDelayFactor))

Count of exponential calculations before return max delay to prevent overflow with big numbers.

Functions

func CalculateDelay

func CalculateDelay(initialDelay time.Duration, retryCount int) time.Duration

CalculateDelay returns delay distributed from initialDelay to default maxDelay (32s)

Example:

Retry 0: 5s
Retry 1: 6s
Retry 2: 7.8s
Retry 3: 9.8s
Retry 4: 13s
Retry 5: 21s
Retry 6: 32s
Retry 7: 32s

func CalculateDelayWithMax

func CalculateDelayWithMax(initialDelay time.Duration, maxDelay time.Duration, retryCount int) time.Duration

CalculateDelayWithMax returns delay distributed from initialDelay to maxDelay based on retryCount number.

Delay for retry number 0 is an initialDelay.

Calculation of exponential delays starts from retry number 1.

After ExponentialCalculationsCount rounds of calculations, maxDelay is returned.