diff options
Diffstat (limited to 'Godeps/_workspace/src/github.com/rcrowley/go-metrics/histogram.go')
-rw-r--r-- | Godeps/_workspace/src/github.com/rcrowley/go-metrics/histogram.go | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/Godeps/_workspace/src/github.com/rcrowley/go-metrics/histogram.go b/Godeps/_workspace/src/github.com/rcrowley/go-metrics/histogram.go new file mode 100644 index 000000000..dbc837fe4 --- /dev/null +++ b/Godeps/_workspace/src/github.com/rcrowley/go-metrics/histogram.go @@ -0,0 +1,202 @@ +package metrics + +// Histograms calculate distribution statistics from a series of int64 values. +type Histogram interface { + Clear() + Count() int64 + Max() int64 + Mean() float64 + Min() int64 + Percentile(float64) float64 + Percentiles([]float64) []float64 + Sample() Sample + Snapshot() Histogram + StdDev() float64 + Sum() int64 + Update(int64) + Variance() float64 +} + +// GetOrRegisterHistogram returns an existing Histogram or constructs and +// registers a new StandardHistogram. +func GetOrRegisterHistogram(name string, r Registry, s Sample) Histogram { + if nil == r { + r = DefaultRegistry + } + return r.GetOrRegister(name, func() Histogram { return NewHistogram(s) }).(Histogram) +} + +// NewHistogram constructs a new StandardHistogram from a Sample. +func NewHistogram(s Sample) Histogram { + if UseNilMetrics { + return NilHistogram{} + } + return &StandardHistogram{sample: s} +} + +// NewRegisteredHistogram constructs and registers a new StandardHistogram from +// a Sample. +func NewRegisteredHistogram(name string, r Registry, s Sample) Histogram { + c := NewHistogram(s) + if nil == r { + r = DefaultRegistry + } + r.Register(name, c) + return c +} + +// HistogramSnapshot is a read-only copy of another Histogram. +type HistogramSnapshot struct { + sample *SampleSnapshot +} + +// Clear panics. +func (*HistogramSnapshot) Clear() { + panic("Clear called on a HistogramSnapshot") +} + +// Count returns the number of samples recorded at the time the snapshot was +// taken. +func (h *HistogramSnapshot) Count() int64 { return h.sample.Count() } + +// Max returns the maximum value in the sample at the time the snapshot was +// taken. +func (h *HistogramSnapshot) Max() int64 { return h.sample.Max() } + +// Mean returns the mean of the values in the sample at the time the snapshot +// was taken. +func (h *HistogramSnapshot) Mean() float64 { return h.sample.Mean() } + +// Min returns the minimum value in the sample at the time the snapshot was +// taken. +func (h *HistogramSnapshot) Min() int64 { return h.sample.Min() } + +// Percentile returns an arbitrary percentile of values in the sample at the +// time the snapshot was taken. +func (h *HistogramSnapshot) Percentile(p float64) float64 { + return h.sample.Percentile(p) +} + +// Percentiles returns a slice of arbitrary percentiles of values in the sample +// at the time the snapshot was taken. +func (h *HistogramSnapshot) Percentiles(ps []float64) []float64 { + return h.sample.Percentiles(ps) +} + +// Sample returns the Sample underlying the histogram. +func (h *HistogramSnapshot) Sample() Sample { return h.sample } + +// Snapshot returns the snapshot. +func (h *HistogramSnapshot) Snapshot() Histogram { return h } + +// StdDev returns the standard deviation of the values in the sample at the +// time the snapshot was taken. +func (h *HistogramSnapshot) StdDev() float64 { return h.sample.StdDev() } + +// Sum returns the sum in the sample at the time the snapshot was taken. +func (h *HistogramSnapshot) Sum() int64 { return h.sample.Sum() } + +// Update panics. +func (*HistogramSnapshot) Update(int64) { + panic("Update called on a HistogramSnapshot") +} + +// Variance returns the variance of inputs at the time the snapshot was taken. +func (h *HistogramSnapshot) Variance() float64 { return h.sample.Variance() } + +// NilHistogram is a no-op Histogram. +type NilHistogram struct{} + +// Clear is a no-op. +func (NilHistogram) Clear() {} + +// Count is a no-op. +func (NilHistogram) Count() int64 { return 0 } + +// Max is a no-op. +func (NilHistogram) Max() int64 { return 0 } + +// Mean is a no-op. +func (NilHistogram) Mean() float64 { return 0.0 } + +// Min is a no-op. +func (NilHistogram) Min() int64 { return 0 } + +// Percentile is a no-op. +func (NilHistogram) Percentile(p float64) float64 { return 0.0 } + +// Percentiles is a no-op. +func (NilHistogram) Percentiles(ps []float64) []float64 { + return make([]float64, len(ps)) +} + +// Sample is a no-op. +func (NilHistogram) Sample() Sample { return NilSample{} } + +// Snapshot is a no-op. +func (NilHistogram) Snapshot() Histogram { return NilHistogram{} } + +// StdDev is a no-op. +func (NilHistogram) StdDev() float64 { return 0.0 } + +// Sum is a no-op. +func (NilHistogram) Sum() int64 { return 0 } + +// Update is a no-op. +func (NilHistogram) Update(v int64) {} + +// Variance is a no-op. +func (NilHistogram) Variance() float64 { return 0.0 } + +// StandardHistogram is the standard implementation of a Histogram and uses a +// Sample to bound its memory use. +type StandardHistogram struct { + sample Sample +} + +// Clear clears the histogram and its sample. +func (h *StandardHistogram) Clear() { h.sample.Clear() } + +// Count returns the number of samples recorded since the histogram was last +// cleared. +func (h *StandardHistogram) Count() int64 { return h.sample.Count() } + +// Max returns the maximum value in the sample. +func (h *StandardHistogram) Max() int64 { return h.sample.Max() } + +// Mean returns the mean of the values in the sample. +func (h *StandardHistogram) Mean() float64 { return h.sample.Mean() } + +// Min returns the minimum value in the sample. +func (h *StandardHistogram) Min() int64 { return h.sample.Min() } + +// Percentile returns an arbitrary percentile of the values in the sample. +func (h *StandardHistogram) Percentile(p float64) float64 { + return h.sample.Percentile(p) +} + +// Percentiles returns a slice of arbitrary percentiles of the values in the +// sample. +func (h *StandardHistogram) Percentiles(ps []float64) []float64 { + return h.sample.Percentiles(ps) +} + +// Sample returns the Sample underlying the histogram. +func (h *StandardHistogram) Sample() Sample { return h.sample } + +// Snapshot returns a read-only copy of the histogram. +func (h *StandardHistogram) Snapshot() Histogram { + return &HistogramSnapshot{sample: h.sample.Snapshot().(*SampleSnapshot)} +} + +// StdDev returns the standard deviation of the values in the sample. +func (h *StandardHistogram) StdDev() float64 { return h.sample.StdDev() } + +// Sum returns the sum in the sample. +func (h *StandardHistogram) Sum() int64 { return h.sample.Sum() } + +// Update samples a new value. +func (h *StandardHistogram) Update(v int64) { h.sample.Update(v) } + +// Variance returns the variance of the values in the sample. +func (h *StandardHistogram) Variance() float64 { return h.sample.Variance() } |