mirror of https://github.com/jech/galene.git
55 lines
880 B
Go
55 lines
880 B
Go
package estimator
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import (
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"sync"
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"sync/atomic"
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"time"
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)
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type Estimator struct {
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interval time.Duration
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count uint32
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mu sync.Mutex
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rate uint32
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time time.Time
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}
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func New(interval time.Duration) *Estimator {
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return &Estimator{
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interval: interval,
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time: time.Now(),
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}
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}
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func (e *Estimator) swap(now time.Time) {
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interval := now.Sub(e.time)
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count := atomic.SwapUint32(&e.count, 0)
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if interval < time.Millisecond {
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e.rate = 0
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} else {
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e.rate = uint32(uint64(count*1000) / uint64(interval/time.Millisecond))
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}
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e.time = now
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}
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func (e *Estimator) Add(count uint32) {
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atomic.AddUint32(&e.count, count)
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}
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func (e *Estimator) estimate(now time.Time) uint32 {
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if now.Sub(e.time) > e.interval {
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e.swap(now)
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}
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return e.rate
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}
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func (e *Estimator) Estimate() uint32 {
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now := time.Now()
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e.mu.Lock()
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defer e.mu.Unlock()
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return e.estimate(now)
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}
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