prometheus/tsdb/tsdbutil/histogram.go
Filip Petkovski be7a4c9b83
Ignore stale histograms for counter reset detection
The histogram stats decoder keeps track of the last seen histogram sample
in order to properly detect counter resets. We are seeing an issue where
a histogram with UnknownResetHint gets treated as a counter reset when it follows
a stale histogram sample.

I believe that this is incorrect since stale samples should be completely ignored
in PromQL. As a result, they should not be stored in the histogram stats iterator
and the counter reset detection needs to be done against the last non-stale sample.

Signed-off-by: Filip Petkovski <filip.petkovsky@gmail.com>
2024-07-26 10:08:31 +02:00

167 lines
4.7 KiB
Go

// Copyright 2023 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package tsdbutil
import (
"math"
"github.com/prometheus/prometheus/model/histogram"
)
func GenerateTestHistograms(n int) (r []*histogram.Histogram) {
for i := 0; i < n; i++ {
h := GenerateTestHistogram(i)
if i > 0 {
h.CounterResetHint = histogram.NotCounterReset
}
r = append(r, h)
}
return r
}
func GenerateTestHistogramWithHint(n int, hint histogram.CounterResetHint) *histogram.Histogram {
h := GenerateTestHistogram(n)
h.CounterResetHint = hint
return h
}
// GenerateTestHistogram but it is up to the user to set any known counter reset hint.
func GenerateTestHistogram(i int) *histogram.Histogram {
return &histogram.Histogram{
Count: 12 + uint64(i*9),
ZeroCount: 2 + uint64(i),
ZeroThreshold: 0.001,
Sum: 18.4 * float64(i+1),
Schema: 1,
PositiveSpans: []histogram.Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{int64(i + 1), 1, -1, 0},
NegativeSpans: []histogram.Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
NegativeBuckets: []int64{int64(i + 1), 1, -1, 0},
}
}
func GenerateTestCustomBucketsHistogram(i int) *histogram.Histogram {
return &histogram.Histogram{
Count: 5 + uint64(i*4),
Sum: 18.4 * float64(i+1),
Schema: histogram.CustomBucketsSchema,
PositiveSpans: []histogram.Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{int64(i + 1), 1, -1, 0},
CustomValues: []float64{0, 1, 2, 3, 4},
}
}
func GenerateTestGaugeHistograms(n int) (r []*histogram.Histogram) {
for x := 0; x < n; x++ {
i := int(math.Sin(float64(x))*100) + 100
r = append(r, GenerateTestGaugeHistogram(i))
}
return r
}
func GenerateTestGaugeHistogram(i int) *histogram.Histogram {
h := GenerateTestHistogram(i)
h.CounterResetHint = histogram.GaugeType
return h
}
func GenerateTestFloatHistograms(n int) (r []*histogram.FloatHistogram) {
for i := 0; i < n; i++ {
h := GenerateTestFloatHistogram(i)
if i > 0 {
h.CounterResetHint = histogram.NotCounterReset
}
r = append(r, h)
}
return r
}
// GenerateTestFloatHistogram but it is up to the user to set any known counter reset hint.
func GenerateTestFloatHistogram(i int) *histogram.FloatHistogram {
return &histogram.FloatHistogram{
Count: 12 + float64(i*9),
ZeroCount: 2 + float64(i),
ZeroThreshold: 0.001,
Sum: 18.4 * float64(i+1),
Schema: 1,
PositiveSpans: []histogram.Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []float64{float64(i + 1), float64(i + 2), float64(i + 1), float64(i + 1)},
NegativeSpans: []histogram.Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
NegativeBuckets: []float64{float64(i + 1), float64(i + 2), float64(i + 1), float64(i + 1)},
}
}
func GenerateTestCustomBucketsFloatHistogram(i int) *histogram.FloatHistogram {
return &histogram.FloatHistogram{
Count: 5 + float64(i*4),
Sum: 18.4 * float64(i+1),
Schema: histogram.CustomBucketsSchema,
PositiveSpans: []histogram.Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []float64{float64(i + 1), float64(i + 2), float64(i + 1), float64(i + 1)},
CustomValues: []float64{0, 1, 2, 3, 4},
}
}
func GenerateTestGaugeFloatHistograms(n int) (r []*histogram.FloatHistogram) {
for x := 0; x < n; x++ {
i := int(math.Sin(float64(x))*100) + 100
r = append(r, GenerateTestGaugeFloatHistogram(i))
}
return r
}
func GenerateTestGaugeFloatHistogram(i int) *histogram.FloatHistogram {
h := GenerateTestFloatHistogram(i)
h.CounterResetHint = histogram.GaugeType
return h
}
func SetHistogramNotCounterReset(h *histogram.Histogram) *histogram.Histogram {
h.CounterResetHint = histogram.NotCounterReset
return h
}
func SetHistogramCounterReset(h *histogram.Histogram) *histogram.Histogram {
h.CounterResetHint = histogram.CounterReset
return h
}
func SetFloatHistogramNotCounterReset(h *histogram.FloatHistogram) *histogram.FloatHistogram {
h.CounterResetHint = histogram.NotCounterReset
return h
}
func SetFloatHistogramCounterReset(h *histogram.FloatHistogram) *histogram.FloatHistogram {
h.CounterResetHint = histogram.CounterReset
return h
}