2018-10-03 09:55:26 -07:00

29 lines
743 B
Go

// Copyright 2016 Michal Witkowski. All Rights Reserved.
// See LICENSE for licensing terms.
/*
Backoff Helper Utilities
Implements common backoff features.
*/
package backoffutils
import (
"math/rand"
"time"
)
// JitterUp adds random jitter to the duration.
//
// This adds or substracts time from the duration within a given jitter fraction.
// For example for 10s and jitter 0.1, it will returna time within [9s, 11s])
func JitterUp(duration time.Duration, jitter float64) time.Duration {
multiplier := jitter * (rand.Float64()*2 - 1)
return time.Duration(float64(duration) * (1 + multiplier))
}
// ExponentBase2 computes 2^(a-1) where a >= 1. If a is 0, the result is 0.
func ExponentBase2(a uint) uint {
return (1 << a) >> 1
}