blob: 5c52894f9eb0203f56fb9cd0e733afcf5ed4a120 (
plain)
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
|
// Copyright (c) Tailscale Inc & contributors
// SPDX-License-Identifier: BSD-3-Clause
package prober
import (
"slices"
"sync"
)
// histogram serves as an adapter to the Prometheus histogram datatype.
// The prober framework passes labels at custom metric collection time that
// it expects to be coupled with the returned metrics. See ProbeClass.Metrics
// and its call sites. Native prometheus histograms cannot be collected while
// injecting more labels. Instead we use this type and pass observations +
// collection labels to prometheus.MustNewConstHistogram() at prometheus
// metric collection time.
type histogram struct {
count uint64
sum float64
buckets []float64
bucketedCounts map[float64]uint64
mx sync.Mutex
}
// newHistogram constructs a histogram that buckets data based on the given
// slice of upper bounds.
func newHistogram(buckets []float64) *histogram {
slices.Sort(buckets)
return &histogram{
buckets: buckets,
bucketedCounts: make(map[float64]uint64, len(buckets)),
}
}
func (h *histogram) add(v float64) {
h.mx.Lock()
defer h.mx.Unlock()
h.count++
h.sum += v
for _, b := range h.buckets {
if v > b {
continue
}
h.bucketedCounts[b] += 1
}
}
|
