peridot/vendor/github.com/grpc-ecosystem/go-grpc-middleware/util/backoffutils/backoff.go

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2022-07-07 20:11:50 +00:00
// 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 subtracts time from the duration within a given jitter fraction.
// For example for 10s and jitter 0.1, it will return a 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
}