// NewHistogram creates a new windowed HDRHistogram with the given parameters.
// Data is kept in the active window for approximately the given duration.
// See the the documentation for hdrhistogram.WindowedHistogram for details.
func NewHistogram(duration time.Duration, maxVal int64, sigFigs int) *Histogram {
h := &Histogram{}
h.maxVal = int64(maxVal)
h.interval = duration / histWrapNum
h.nextT = now()
h.windowed = hdrhistogram.NewWindowed(histWrapNum, 0, h.maxVal, sigFigs)
return h
}
func newWindowedHistogram(name string, minValue, maxValue int64, sigfigs int, quantiles map[int]metrics.Gauge, logger log.Logger) *windowedHistogram {
h := &windowedHistogram{
hist: hdrhistogram.NewWindowed(5, minValue, maxValue, sigfigs),
name: name,
gauges: quantiles,
logger: logger,
}
go h.rotateLoop(1 * time.Minute)
return h
}
// newSlidingHistogram creates a new windowed HDRHistogram with the given
// parameters. Data is kept in the active window for approximately the given
// duration. See the documentation for hdrhistogram.WindowedHistogram for
// details.
func newSlidingHistogram(duration time.Duration, maxVal int64, sigFigs int) *slidingHistogram {
if duration <= 0 {
panic("cannot create a sliding histogram with nonpositive duration")
}
return &slidingHistogram{
nextT: now(),
duration: duration,
windowed: hdrhistogram.NewWindowed(histWrapNum, 0, maxVal, sigFigs),
}
}
// NewHistogram creates a new windowed HDRHistogram with the given parameters.
// Data is kept in the active window for approximately the given duration.
// See the documentation for hdrhistogram.WindowedHistogram for details.
func NewHistogram(metadata Metadata, duration time.Duration,
maxVal int64, sigFigs int) *Histogram {
return &Histogram{
Metadata: metadata,
maxVal: maxVal,
nextT: now(),
duration: duration,
windowed: hdrhistogram.NewWindowed(histWrapNum, 0, maxVal, sigFigs),
}
}
func BenchmarkWindowedHistogramRecordAndRotate(b *testing.B) {
w := hdrhistogram.NewWindowed(3, 1, 10000000, 3)
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i++ {
if err := w.Current.RecordValue(100); err != nil {
b.Fatal(err)
}
if i%100000 == 1 {
w.Rotate()
}
}
}
// NewHistogram is taken from http://github.com/codahale/metrics. It returns a
// windowed HDR histogram which drops data older than five minutes.
//
// The histogram exposes metrics for each passed quantile as gauges. Quantiles
// should be integers in the range 1..99. The gauge names are assigned by
// using the passed name as a prefix and appending "_pNN" e.g. "_p50".
func NewHistogram(name string, minValue, maxValue int64, sigfigs int, quantiles ...int) metrics.Histogram {
gauges := map[int]metrics.Gauge{}
for _, quantile := range quantiles {
if quantile <= 0 || quantile >= 100 {
panic(fmt.Sprintf("invalid quantile %d", quantile))
}
gauges[quantile] = NewGauge(fmt.Sprintf("%s_p%02d", name, quantile))
}
h := &histogram{
hist: hdrhistogram.NewWindowed(5, minValue, maxValue, sigfigs),
name: name,
gauges: gauges,
}
go h.rotateLoop(1 * time.Minute)
return h
}
// NewHistogramTick is the same as NewHistoGram, but allows to pass a custom reportTicker.
func NewHistogramTick(client stdinflux.Client, bp stdinflux.BatchPoints, key string, tags []metrics.Field,
reportTicker <-chan time.Time, minValue, maxValue int64, sigfigs int, quantiles ...int) metrics.Histogram {
gauges := map[int]metrics.Gauge{}
for _, quantile := range quantiles {
if quantile <= 0 || quantile >= 100 {
panic(fmt.Sprintf("invalid quantile %d", quantile))
}
gauges[quantile] = NewGaugeTick(client, bp, fmt.Sprintf("%s_p%02d", key, quantile), tags, reportTicker)
}
h := &histogram{
hist: hdrhistogram.NewWindowed(5, minValue, maxValue, sigfigs),
key: key,
gauges: gauges,
}
go h.rotateLoop(1 * time.Minute)
return h
}
func TestWindowedHistogram(t *testing.T) {
w := hdrhistogram.NewWindowed(2, 1, 1000, 3)
for i := 0; i < 100; i++ {
w.Current.RecordValue(int64(i))
}
w.Rotate()
for i := 100; i < 200; i++ {
w.Current.RecordValue(int64(i))
}
w.Rotate()
for i := 200; i < 300; i++ {
w.Current.RecordValue(int64(i))
}
if v, want := w.Merge().ValueAtQuantile(50), int64(199); v != want {
t.Errorf("Median was %v, but expected %v", v, want)
}
}
// NewHistogram returns a windowed HDR histogram which drops data older than
// five minutes. The returned histogram is safe to use from multiple goroutines.
//
// Use a histogram to track the distribution of a stream of values (e.g., the
// latency associated with HTTP requests).
func NewHistogram(name string, minValue, maxValue int64, sigfigs int) *Histogram {
hm.Lock()
defer hm.Unlock()
if _, ok := histograms[name]; ok {
panic(name + " already exists")
}
hist := &Histogram{
name: name,
hist: hdrhistogram.NewWindowed(5, minValue, maxValue, sigfigs),
}
histograms[name] = hist
Gauge(name+".P50").SetBatchFunc(hname(name), hist.merge, hist.valueAt(50))
Gauge(name+".P75").SetBatchFunc(hname(name), hist.merge, hist.valueAt(75))
Gauge(name+".P90").SetBatchFunc(hname(name), hist.merge, hist.valueAt(90))
Gauge(name+".P95").SetBatchFunc(hname(name), hist.merge, hist.valueAt(95))
Gauge(name+".P99").SetBatchFunc(hname(name), hist.merge, hist.valueAt(99))
Gauge(name+".P999").SetBatchFunc(hname(name), hist.merge, hist.valueAt(99.9))
return hist
}
