forked from go-kit/kit
-
Notifications
You must be signed in to change notification settings - Fork 0
/
generic.go
247 lines (214 loc) · 5.71 KB
/
generic.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
// Package generic implements generic versions of each of the metric types. They
// can be embedded by other implementations, and converted to specific formats
// as necessary.
package generic
import (
"fmt"
"io"
"math"
"sync"
"sync/atomic"
"github.com/VividCortex/gohistogram"
"github.com/AshleyDumaine/kit/metrics"
"github.com/AshleyDumaine/kit/metrics/internal/lv"
)
// Counter is an in-memory implementation of a Counter.
type Counter struct {
Name string
lvs lv.LabelValues
bits uint64
}
// NewCounter returns a new, usable Counter.
func NewCounter(name string) *Counter {
return &Counter{
Name: name,
}
}
// With implements Counter.
func (c *Counter) With(labelValues ...string) metrics.Counter {
return &Counter{
Name: c.Name,
bits: atomic.LoadUint64(&c.bits),
lvs: c.lvs.With(labelValues...),
}
}
// Add implements Counter.
func (c *Counter) Add(delta float64) {
for {
var (
old = atomic.LoadUint64(&c.bits)
newf = math.Float64frombits(old) + delta
new = math.Float64bits(newf)
)
if atomic.CompareAndSwapUint64(&c.bits, old, new) {
break
}
}
}
// Value returns the current value of the counter.
func (c *Counter) Value() float64 {
return math.Float64frombits(atomic.LoadUint64(&c.bits))
}
// ValueReset returns the current value of the counter, and resets it to zero.
// This is useful for metrics backends whose counter aggregations expect deltas,
// like Graphite.
func (c *Counter) ValueReset() float64 {
for {
var (
old = atomic.LoadUint64(&c.bits)
newf = 0.0
new = math.Float64bits(newf)
)
if atomic.CompareAndSwapUint64(&c.bits, old, new) {
return math.Float64frombits(old)
}
}
}
// LabelValues returns the set of label values attached to the counter.
func (c *Counter) LabelValues() []string {
return c.lvs
}
// Gauge is an in-memory implementation of a Gauge.
type Gauge struct {
Name string
lvs lv.LabelValues
bits uint64
}
// NewGauge returns a new, usable Gauge.
func NewGauge(name string) *Gauge {
return &Gauge{
Name: name,
}
}
// With implements Gauge.
func (g *Gauge) With(labelValues ...string) metrics.Gauge {
return &Gauge{
Name: g.Name,
bits: atomic.LoadUint64(&g.bits),
lvs: g.lvs.With(labelValues...),
}
}
// Set implements Gauge.
func (g *Gauge) Set(value float64) {
atomic.StoreUint64(&g.bits, math.Float64bits(value))
}
// Add implements metrics.Gauge.
func (g *Gauge) Add(delta float64) {
for {
var (
old = atomic.LoadUint64(&g.bits)
newf = math.Float64frombits(old) + delta
new = math.Float64bits(newf)
)
if atomic.CompareAndSwapUint64(&g.bits, old, new) {
break
}
}
}
// Value returns the current value of the gauge.
func (g *Gauge) Value() float64 {
return math.Float64frombits(atomic.LoadUint64(&g.bits))
}
// LabelValues returns the set of label values attached to the gauge.
func (g *Gauge) LabelValues() []string {
return g.lvs
}
// Histogram is an in-memory implementation of a streaming histogram, based on
// VividCortex/gohistogram. It dynamically computes quantiles, so it's not
// suitable for aggregation.
type Histogram struct {
Name string
lvs lv.LabelValues
h *safeHistogram
}
// NewHistogram returns a numeric histogram based on VividCortex/gohistogram. A
// good default value for buckets is 50.
func NewHistogram(name string, buckets int) *Histogram {
return &Histogram{
Name: name,
h: &safeHistogram{Histogram: gohistogram.NewHistogram(buckets)},
}
}
// With implements Histogram.
func (h *Histogram) With(labelValues ...string) metrics.Histogram {
return &Histogram{
Name: h.Name,
lvs: h.lvs.With(labelValues...),
h: h.h,
}
}
// Observe implements Histogram.
func (h *Histogram) Observe(value float64) {
h.h.Lock()
defer h.h.Unlock()
h.h.Add(value)
}
// Quantile returns the value of the quantile q, 0.0 < q < 1.0.
func (h *Histogram) Quantile(q float64) float64 {
h.h.RLock()
defer h.h.RUnlock()
return h.h.Quantile(q)
}
// LabelValues returns the set of label values attached to the histogram.
func (h *Histogram) LabelValues() []string {
return h.lvs
}
// Print writes a string representation of the histogram to the passed writer.
// Useful for printing to a terminal.
func (h *Histogram) Print(w io.Writer) {
h.h.RLock()
defer h.h.RUnlock()
fmt.Fprintf(w, h.h.String())
}
// safeHistogram exists as gohistogram.Histogram is not goroutine-safe.
type safeHistogram struct {
sync.RWMutex
gohistogram.Histogram
}
// Bucket is a range in a histogram which aggregates observations.
type Bucket struct {
From, To, Count int64
}
// Quantile is a pair of a quantile (0..100) and its observed maximum value.
type Quantile struct {
Quantile int // 0..100
Value int64
}
// SimpleHistogram is an in-memory implementation of a Histogram. It only tracks
// an approximate moving average, so is likely too naïve for many use cases.
type SimpleHistogram struct {
mtx sync.RWMutex
lvs lv.LabelValues
avg float64
n uint64
}
// NewSimpleHistogram returns a SimpleHistogram, ready for observations.
func NewSimpleHistogram() *SimpleHistogram {
return &SimpleHistogram{}
}
// With implements Histogram.
func (h *SimpleHistogram) With(labelValues ...string) metrics.Histogram {
return &SimpleHistogram{
lvs: h.lvs.With(labelValues...),
avg: h.avg,
n: h.n,
}
}
// Observe implements Histogram.
func (h *SimpleHistogram) Observe(value float64) {
h.mtx.Lock()
defer h.mtx.Unlock()
h.n++
h.avg -= h.avg / float64(h.n)
h.avg += value / float64(h.n)
}
// ApproximateMovingAverage returns the approximate moving average of observations.
func (h *SimpleHistogram) ApproximateMovingAverage() float64 {
h.mtx.RLock()
defer h.mtx.RUnlock()
return h.avg
}
// LabelValues returns the set of label values attached to the histogram.
func (h *SimpleHistogram) LabelValues() []string {
return h.lvs
}