37 lines
911 B
Go
37 lines
911 B
Go
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// These functions are coming from consul/lib/cluster.go
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package helper
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import (
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"math/rand"
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"time"
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)
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const (
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// minRate is the minimum rate at which we allow an action to be performed
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// across the whole cluster. The value is once a day: 1 / (1 * time.Day)
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minRate = 1.0 / 86400
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)
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// RandomStagger returns an interval between 0 and the duration
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func RandomStagger(intv time.Duration) time.Duration {
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if intv == 0 {
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return 0
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}
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return time.Duration(uint64(rand.Int63()) % uint64(intv))
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}
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// RateScaledInterval is used to choose an interval to perform an action in
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// order to target an aggregate number of actions per second across the whole
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// cluster.
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func RateScaledInterval(rate float64, min time.Duration, n int) time.Duration {
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if rate <= minRate {
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return min
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}
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interval := time.Duration(float64(time.Second) * float64(n) / rate)
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if interval < min {
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return min
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}
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return interval
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}
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