bsc/metrics/timer.go
2019-11-22 16:04:35 +01:00

327 lines
8.6 KiB
Go

package metrics
import (
"sync"
"time"
)
// Timers capture the duration and rate of events.
type Timer interface {
Count() int64
Max() int64
Mean() float64
Min() int64
Percentile(float64) float64
Percentiles([]float64) []float64
Rate1() float64
Rate5() float64
Rate15() float64
RateMean() float64
Snapshot() Timer
StdDev() float64
Stop()
Sum() int64
Time(func())
Update(time.Duration)
UpdateSince(time.Time)
Variance() float64
}
// GetOrRegisterTimer returns an existing Timer or constructs and registers a
// new StandardTimer.
// Be sure to unregister the meter from the registry once it is of no use to
// allow for garbage collection.
func GetOrRegisterTimer(name string, r Registry) Timer {
if nil == r {
r = DefaultRegistry
}
return r.GetOrRegister(name, NewTimer).(Timer)
}
// NewCustomTimer constructs a new StandardTimer from a Histogram and a Meter.
// Be sure to call Stop() once the timer is of no use to allow for garbage collection.
func NewCustomTimer(h Histogram, m Meter) Timer {
if !Enabled {
return NilTimer{}
}
return &StandardTimer{
histogram: h,
meter: m,
}
}
// NewRegisteredTimer constructs and registers a new StandardTimer.
// Be sure to unregister the meter from the registry once it is of no use to
// allow for garbage collection.
func NewRegisteredTimer(name string, r Registry) Timer {
c := NewTimer()
if nil == r {
r = DefaultRegistry
}
r.Register(name, c)
return c
}
// NewTimer constructs a new StandardTimer using an exponentially-decaying
// sample with the same reservoir size and alpha as UNIX load averages.
// Be sure to call Stop() once the timer is of no use to allow for garbage collection.
func NewTimer() Timer {
if !Enabled {
return NilTimer{}
}
return &StandardTimer{
histogram: NewHistogram(NewExpDecaySample(1028, 0.015)),
meter: NewMeter(),
}
}
// NilTimer is a no-op Timer.
type NilTimer struct{}
// Count is a no-op.
func (NilTimer) Count() int64 { return 0 }
// Max is a no-op.
func (NilTimer) Max() int64 { return 0 }
// Mean is a no-op.
func (NilTimer) Mean() float64 { return 0.0 }
// Min is a no-op.
func (NilTimer) Min() int64 { return 0 }
// Percentile is a no-op.
func (NilTimer) Percentile(p float64) float64 { return 0.0 }
// Percentiles is a no-op.
func (NilTimer) Percentiles(ps []float64) []float64 {
return make([]float64, len(ps))
}
// Rate1 is a no-op.
func (NilTimer) Rate1() float64 { return 0.0 }
// Rate5 is a no-op.
func (NilTimer) Rate5() float64 { return 0.0 }
// Rate15 is a no-op.
func (NilTimer) Rate15() float64 { return 0.0 }
// RateMean is a no-op.
func (NilTimer) RateMean() float64 { return 0.0 }
// Snapshot is a no-op.
func (NilTimer) Snapshot() Timer { return NilTimer{} }
// StdDev is a no-op.
func (NilTimer) StdDev() float64 { return 0.0 }
// Stop is a no-op.
func (NilTimer) Stop() {}
// Sum is a no-op.
func (NilTimer) Sum() int64 { return 0 }
// Time is a no-op.
func (NilTimer) Time(func()) {}
// Update is a no-op.
func (NilTimer) Update(time.Duration) {}
// UpdateSince is a no-op.
func (NilTimer) UpdateSince(time.Time) {}
// Variance is a no-op.
func (NilTimer) Variance() float64 { return 0.0 }
// StandardTimer is the standard implementation of a Timer and uses a Histogram
// and Meter.
type StandardTimer struct {
histogram Histogram
meter Meter
mutex sync.Mutex
}
// Count returns the number of events recorded.
func (t *StandardTimer) Count() int64 {
return t.histogram.Count()
}
// Max returns the maximum value in the sample.
func (t *StandardTimer) Max() int64 {
return t.histogram.Max()
}
// Mean returns the mean of the values in the sample.
func (t *StandardTimer) Mean() float64 {
return t.histogram.Mean()
}
// Min returns the minimum value in the sample.
func (t *StandardTimer) Min() int64 {
return t.histogram.Min()
}
// Percentile returns an arbitrary percentile of the values in the sample.
func (t *StandardTimer) Percentile(p float64) float64 {
return t.histogram.Percentile(p)
}
// Percentiles returns a slice of arbitrary percentiles of the values in the
// sample.
func (t *StandardTimer) Percentiles(ps []float64) []float64 {
return t.histogram.Percentiles(ps)
}
// Rate1 returns the one-minute moving average rate of events per second.
func (t *StandardTimer) Rate1() float64 {
return t.meter.Rate1()
}
// Rate5 returns the five-minute moving average rate of events per second.
func (t *StandardTimer) Rate5() float64 {
return t.meter.Rate5()
}
// Rate15 returns the fifteen-minute moving average rate of events per second.
func (t *StandardTimer) Rate15() float64 {
return t.meter.Rate15()
}
// RateMean returns the meter's mean rate of events per second.
func (t *StandardTimer) RateMean() float64 {
return t.meter.RateMean()
}
// Snapshot returns a read-only copy of the timer.
func (t *StandardTimer) Snapshot() Timer {
t.mutex.Lock()
defer t.mutex.Unlock()
return &TimerSnapshot{
histogram: t.histogram.Snapshot().(*HistogramSnapshot),
meter: t.meter.Snapshot().(*MeterSnapshot),
}
}
// StdDev returns the standard deviation of the values in the sample.
func (t *StandardTimer) StdDev() float64 {
return t.histogram.StdDev()
}
// Stop stops the meter.
func (t *StandardTimer) Stop() {
t.meter.Stop()
}
// Sum returns the sum in the sample.
func (t *StandardTimer) Sum() int64 {
return t.histogram.Sum()
}
// Record the duration of the execution of the given function.
func (t *StandardTimer) Time(f func()) {
ts := time.Now()
f()
t.Update(time.Since(ts))
}
// Record the duration of an event.
func (t *StandardTimer) Update(d time.Duration) {
t.mutex.Lock()
defer t.mutex.Unlock()
t.histogram.Update(int64(d))
t.meter.Mark(1)
}
// Record the duration of an event that started at a time and ends now.
func (t *StandardTimer) UpdateSince(ts time.Time) {
t.mutex.Lock()
defer t.mutex.Unlock()
t.histogram.Update(int64(time.Since(ts)))
t.meter.Mark(1)
}
// Variance returns the variance of the values in the sample.
func (t *StandardTimer) Variance() float64 {
return t.histogram.Variance()
}
// TimerSnapshot is a read-only copy of another Timer.
type TimerSnapshot struct {
histogram *HistogramSnapshot
meter *MeterSnapshot
}
// Count returns the number of events recorded at the time the snapshot was
// taken.
func (t *TimerSnapshot) Count() int64 { return t.histogram.Count() }
// Max returns the maximum value at the time the snapshot was taken.
func (t *TimerSnapshot) Max() int64 { return t.histogram.Max() }
// Mean returns the mean value at the time the snapshot was taken.
func (t *TimerSnapshot) Mean() float64 { return t.histogram.Mean() }
// Min returns the minimum value at the time the snapshot was taken.
func (t *TimerSnapshot) Min() int64 { return t.histogram.Min() }
// Percentile returns an arbitrary percentile of sampled values at the time the
// snapshot was taken.
func (t *TimerSnapshot) Percentile(p float64) float64 {
return t.histogram.Percentile(p)
}
// Percentiles returns a slice of arbitrary percentiles of sampled values at
// the time the snapshot was taken.
func (t *TimerSnapshot) Percentiles(ps []float64) []float64 {
return t.histogram.Percentiles(ps)
}
// Rate1 returns the one-minute moving average rate of events per second at the
// time the snapshot was taken.
func (t *TimerSnapshot) Rate1() float64 { return t.meter.Rate1() }
// Rate5 returns the five-minute moving average rate of events per second at
// the time the snapshot was taken.
func (t *TimerSnapshot) Rate5() float64 { return t.meter.Rate5() }
// Rate15 returns the fifteen-minute moving average rate of events per second
// at the time the snapshot was taken.
func (t *TimerSnapshot) Rate15() float64 { return t.meter.Rate15() }
// RateMean returns the meter's mean rate of events per second at the time the
// snapshot was taken.
func (t *TimerSnapshot) RateMean() float64 { return t.meter.RateMean() }
// Snapshot returns the snapshot.
func (t *TimerSnapshot) Snapshot() Timer { return t }
// StdDev returns the standard deviation of the values at the time the snapshot
// was taken.
func (t *TimerSnapshot) StdDev() float64 { return t.histogram.StdDev() }
// Stop is a no-op.
func (t *TimerSnapshot) Stop() {}
// Sum returns the sum at the time the snapshot was taken.
func (t *TimerSnapshot) Sum() int64 { return t.histogram.Sum() }
// Time panics.
func (*TimerSnapshot) Time(func()) {
panic("Time called on a TimerSnapshot")
}
// Update panics.
func (*TimerSnapshot) Update(time.Duration) {
panic("Update called on a TimerSnapshot")
}
// UpdateSince panics.
func (*TimerSnapshot) UpdateSince(time.Time) {
panic("UpdateSince called on a TimerSnapshot")
}
// Variance returns the variance of the values at the time the snapshot was
// taken.
func (t *TimerSnapshot) Variance() float64 { return t.histogram.Variance() }