diff options
Diffstat (limited to 'metrics/timer.go')
| -rw-r--r-- | metrics/timer.go | 329 |
1 files changed, 329 insertions, 0 deletions
diff --git a/metrics/timer.go b/metrics/timer.go new file mode 100644 index 000000000..89e22208f --- /dev/null +++ b/metrics/timer.go @@ -0,0 +1,329 @@ +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 { + h Histogram + m Meter +} + +// 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() } |