// Copyright 2021 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 histogram
import (
"math"
"strconv"
"testing"
"github.com/stretchr/testify/require"
"github.com/prometheus/prometheus/model/value"
)
func TestHistogramString(t *testing.T) {
cases := []struct {
histogram Histogram
expectedString string
}{
{
histogram: Histogram{
Schema: 0,
},
expectedString: "{count:0, sum:0}",
},
{
histogram: Histogram{
Schema: 0,
Count: 9,
Sum: -3.1415,
ZeroCount: 12,
ZeroThreshold: 0.001,
NegativeSpans: []Span{
{Offset: 0, Length: 5},
{Offset: 1, Length: 1},
},
NegativeBuckets: []int64{1, 2, -2, 1, -1, 0},
},
expectedString: "{count:9, sum:-3.1415, [-64,-32):1, [-16,-8):1, [-8,-4):2, [-4,-2):1, [-2,-1):3, [-1,-0.5):1, [-0.001,0.001]:12}",
},
{
histogram: Histogram{
Schema: 0,
Count: 19,
Sum: 2.7,
PositiveSpans: []Span{
{Offset: 0, Length: 4},
{Offset: 0, Length: 0},
{Offset: 0, Length: 3},
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 0},
NegativeSpans: []Span{
{Offset: 0, Length: 5},
{Offset: 1, Length: 0},
{Offset: 0, Length: 1},
},
NegativeBuckets: []int64{1, 2, -2, 1, -1, 0},
},
expectedString: "{count:19, sum:2.7, [-64,-32):1, [-16,-8):1, [-8,-4):2, [-4,-2):1, [-2,-1):3, [-1,-0.5):1, (0.5,1]:1, (1,2]:3, (2,4]:1, (4,8]:2, (8,16]:1, (16,32]:1, (32,64]:1}",
},
{
histogram: Histogram{
Schema: CustomBucketsSchema,
Count: 19,
Sum: 2.7,
PositiveSpans: []Span{
{Offset: 0, Length: 4},
{Offset: 0, Length: 0},
{Offset: 0, Length: 3},
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 0},
CustomValues: []float64{1, 2, 5, 10, 15, 20, 25, 50},
},
expectedString: "{count:19, sum:2.7, [-Inf,1]:1, (1,2]:3, (2,5]:1, (5,10]:2, (10,15]:1, (15,20]:1, (20,25]:1}",
},
}
for i, c := range cases {
t.Run(strconv.Itoa(i), func(t *testing.T) {
actualString := c.histogram.String()
require.Equal(t, c.expectedString, actualString)
})
}
}
func TestCumulativeBucketIterator(t *testing.T) {
cases := []struct {
histogram Histogram
expectedBuckets []Bucket[uint64]
}{
{
histogram: Histogram{
Schema: 0,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
},
expectedBuckets: []Bucket[uint64]{
{Lower: math.Inf(-1), Upper: 1, Count: 1, LowerInclusive: true, UpperInclusive: true, Index: 0},
{Lower: math.Inf(-1), Upper: 2, Count: 3, LowerInclusive: true, UpperInclusive: true, Index: 1},
{Lower: math.Inf(-1), Upper: 4, Count: 3, LowerInclusive: true, UpperInclusive: true, Index: 2},
{Lower: math.Inf(-1), Upper: 8, Count: 4, LowerInclusive: true, UpperInclusive: true, Index: 3},
{Lower: math.Inf(-1), Upper: 16, Count: 5, LowerInclusive: true, UpperInclusive: true, Index: 4},
},
},
{
histogram: Histogram{
Schema: 0,
PositiveSpans: []Span{
{Offset: 0, Length: 5},
{Offset: 1, Length: 1},
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0},
},
expectedBuckets: []Bucket[uint64]{
{Lower: math.Inf(-1), Upper: 1, Count: 1, LowerInclusive: true, UpperInclusive: true, Index: 0},
{Lower: math.Inf(-1), Upper: 2, Count: 4, LowerInclusive: true, UpperInclusive: true, Index: 1},
{Lower: math.Inf(-1), Upper: 4, Count: 5, LowerInclusive: true, UpperInclusive: true, Index: 2},
{Lower: math.Inf(-1), Upper: 8, Count: 7, LowerInclusive: true, UpperInclusive: true, Index: 3},
{Lower: math.Inf(-1), Upper: 16, Count: 8, LowerInclusive: true, UpperInclusive: true, Index: 4},
{Lower: math.Inf(-1), Upper: 32, Count: 8, LowerInclusive: true, UpperInclusive: true, Index: 5},
{Lower: math.Inf(-1), Upper: 64, Count: 9, LowerInclusive: true, UpperInclusive: true, Index: 6},
},
},
{
histogram: Histogram{
Schema: 0,
PositiveSpans: []Span{
{Offset: 0, Length: 7},
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 0},
},
expectedBuckets: []Bucket[uint64]{
{Lower: math.Inf(-1), Upper: 1, Count: 1, LowerInclusive: true, UpperInclusive: true, Index: 0},
{Lower: math.Inf(-1), Upper: 2, Count: 4, LowerInclusive: true, UpperInclusive: true, Index: 1},
{Lower: math.Inf(-1), Upper: 4, Count: 5, LowerInclusive: true, UpperInclusive: true, Index: 2},
{Lower: math.Inf(-1), Upper: 8, Count: 7, LowerInclusive: true, UpperInclusive: true, Index: 3},
{Lower: math.Inf(-1), Upper: 16, Count: 8, LowerInclusive: true, UpperInclusive: true, Index: 4},
{Lower: math.Inf(-1), Upper: 32, Count: 9, LowerInclusive: true, UpperInclusive: true, Index: 5},
{Lower: math.Inf(-1), Upper: 64, Count: 10, LowerInclusive: true, UpperInclusive: true, Index: 6},
},
},
{
histogram: Histogram{
Schema: 3,
PositiveSpans: []Span{
{Offset: -5, Length: 2}, // -5 -4
{Offset: 2, Length: 3}, // -1 0 1
{Offset: 2, Length: 2}, // 4 5
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 3},
},
expectedBuckets: []Bucket[uint64]{
{Lower: math.Inf(-1), Upper: 0.6484197773255048, Count: 1, LowerInclusive: true, UpperInclusive: true, Index: -5},
{Lower: math.Inf(-1), Upper: 0.7071067811865475, Count: 4, LowerInclusive: true, UpperInclusive: true, Index: -4},
{Lower: math.Inf(-1), Upper: 0.7711054127039704, Count: 4, LowerInclusive: true, UpperInclusive: true, Index: -3},
{Lower: math.Inf(-1), Upper: 0.8408964152537144, Count: 4, LowerInclusive: true, UpperInclusive: true, Index: -2},
{Lower: math.Inf(-1), Upper: 0.9170040432046711, Count: 5, LowerInclusive: true, UpperInclusive: true, Index: -1},
{Lower: math.Inf(-1), Upper: 1, Count: 7, LowerInclusive: true, UpperInclusive: true, Index: 0},
{Lower: math.Inf(-1), Upper: 1.0905077326652577, Count: 8, LowerInclusive: true, UpperInclusive: true, Index: 1},
{Lower: math.Inf(-1), Upper: 1.189207115002721, Count: 8, LowerInclusive: true, UpperInclusive: true, Index: 2},
{Lower: math.Inf(-1), Upper: 1.2968395546510096, Count: 8, LowerInclusive: true, UpperInclusive: true, Index: 3},
{Lower: math.Inf(-1), Upper: 1.414213562373095, Count: 9, LowerInclusive: true, UpperInclusive: true, Index: 4},
{Lower: math.Inf(-1), Upper: 1.5422108254079407, Count: 13, LowerInclusive: true, UpperInclusive: true, Index: 5},
},
},
{
histogram: Histogram{
Schema: -2,
PositiveSpans: []Span{
{Offset: -2, Length: 4}, // -2 -1 0 1
{Offset: 2, Length: 2}, // 4 5
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0},
},
expectedBuckets: []Bucket[uint64]{
{Lower: math.Inf(-1), Upper: 0.00390625, Count: 1, LowerInclusive: true, UpperInclusive: true, Index: -2},
{Lower: math.Inf(-1), Upper: 0.0625, Count: 4, LowerInclusive: true, UpperInclusive: true, Index: -1},
{Lower: math.Inf(-1), Upper: 1, Count: 5, LowerInclusive: true, UpperInclusive: true, Index: 0},
{Lower: math.Inf(-1), Upper: 16, Count: 7, LowerInclusive: true, UpperInclusive: true, Index: 1},
{Lower: math.Inf(-1), Upper: 256, Count: 7, LowerInclusive: true, UpperInclusive: true, Index: 2},
{Lower: math.Inf(-1), Upper: 4096, Count: 7, LowerInclusive: true, UpperInclusive: true, Index: 3},
{Lower: math.Inf(-1), Upper: 65536, Count: 8, LowerInclusive: true, UpperInclusive: true, Index: 4},
{Lower: math.Inf(-1), Upper: 1048576, Count: 9, LowerInclusive: true, UpperInclusive: true, Index: 5},
},
},
{
histogram: Histogram{
Schema: -1,
PositiveSpans: []Span{
{Offset: -2, Length: 5}, // -2 -1 0 1 2
},
PositiveBuckets: []int64{1, 2, -2, 1, -1},
},
expectedBuckets: []Bucket[uint64]{
{Lower: math.Inf(-1), Upper: 0.0625, Count: 1, LowerInclusive: true, UpperInclusive: true, Index: -2},
{Lower: math.Inf(-1), Upper: 0.25, Count: 4, LowerInclusive: true, UpperInclusive: true, Index: -1},
{Lower: math.Inf(-1), Upper: 1, Count: 5, LowerInclusive: true, UpperInclusive: true, Index: 0},
{Lower: math.Inf(-1), Upper: 4, Count: 7, LowerInclusive: true, UpperInclusive: true, Index: 1},
{Lower: math.Inf(-1), Upper: 16, Count: 8, LowerInclusive: true, UpperInclusive: true, Index: 2},
},
},
{
histogram: Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
CustomValues: []float64{5, 10, 20, 50},
},
expectedBuckets: []Bucket[uint64]{
{Lower: math.Inf(-1), Upper: 5, Count: 1, LowerInclusive: true, UpperInclusive: true, Index: 0},
{Lower: math.Inf(-1), Upper: 10, Count: 3, LowerInclusive: true, UpperInclusive: true, Index: 1},
{Lower: math.Inf(-1), Upper: 20, Count: 3, LowerInclusive: true, UpperInclusive: true, Index: 2},
{Lower: math.Inf(-1), Upper: 50, Count: 4, LowerInclusive: true, UpperInclusive: true, Index: 3},
{Lower: math.Inf(-1), Upper: math.Inf(1), Count: 5, LowerInclusive: true, UpperInclusive: true, Index: 4},
},
},
}
for i, c := range cases {
t.Run(strconv.Itoa(i), func(t *testing.T) {
it := c.histogram.CumulativeBucketIterator()
actualBuckets := make([]Bucket[uint64], 0, len(c.expectedBuckets))
for it.Next() {
actualBuckets = append(actualBuckets, it.At())
}
require.Equal(t, c.expectedBuckets, actualBuckets)
})
}
}
func TestRegularBucketIterator(t *testing.T) {
cases := []struct {
histogram Histogram
expectedPositiveBuckets []Bucket[uint64]
expectedNegativeBuckets []Bucket[uint64]
}{
{
histogram: Histogram{
Schema: 0,
},
expectedPositiveBuckets: []Bucket[uint64]{},
expectedNegativeBuckets: []Bucket[uint64]{},
},
{
histogram: Histogram{
Schema: 0,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
},
expectedPositiveBuckets: []Bucket[uint64]{
{Lower: 0.5, Upper: 1, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 0},
{Lower: 1, Upper: 2, Count: 2, LowerInclusive: false, UpperInclusive: true, Index: 1},
{Lower: 4, Upper: 8, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 3},
{Lower: 8, Upper: 16, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 4},
},
expectedNegativeBuckets: []Bucket[uint64]{},
},
{
histogram: Histogram{
Schema: 0,
NegativeSpans: []Span{
{Offset: 0, Length: 5},
{Offset: 1, Length: 1},
},
NegativeBuckets: []int64{1, 2, -2, 1, -1, 0},
},
expectedPositiveBuckets: []Bucket[uint64]{},
expectedNegativeBuckets: []Bucket[uint64]{
{Lower: -1, Upper: -0.5, Count: 1, LowerInclusive: true, UpperInclusive: false, Index: 0},
{Lower: -2, Upper: -1, Count: 3, LowerInclusive: true, UpperInclusive: false, Index: 1},
{Lower: -4, Upper: -2, Count: 1, LowerInclusive: true, UpperInclusive: false, Index: 2},
{Lower: -8, Upper: -4, Count: 2, LowerInclusive: true, UpperInclusive: false, Index: 3},
{Lower: -16, Upper: -8, Count: 1, LowerInclusive: true, UpperInclusive: false, Index: 4},
{Lower: -64, Upper: -32, Count: 1, LowerInclusive: true, UpperInclusive: false, Index: 6},
},
},
{
histogram: Histogram{
Schema: 0,
PositiveSpans: []Span{
{Offset: 0, Length: 4},
{Offset: 0, Length: 0},
{Offset: 0, Length: 3},
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 0},
NegativeSpans: []Span{
{Offset: 0, Length: 5},
{Offset: 1, Length: 0},
{Offset: 0, Length: 1},
},
NegativeBuckets: []int64{1, 2, -2, 1, -1, 0},
},
expectedPositiveBuckets: []Bucket[uint64]{
{Lower: 0.5, Upper: 1, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 0},
{Lower: 1, Upper: 2, Count: 3, LowerInclusive: false, UpperInclusive: true, Index: 1},
{Lower: 2, Upper: 4, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 2},
{Lower: 4, Upper: 8, Count: 2, LowerInclusive: false, UpperInclusive: true, Index: 3},
{Lower: 8, Upper: 16, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 4},
{Lower: 16, Upper: 32, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 5},
{Lower: 32, Upper: 64, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 6},
},
expectedNegativeBuckets: []Bucket[uint64]{
{Lower: -1, Upper: -0.5, Count: 1, LowerInclusive: true, UpperInclusive: false, Index: 0},
{Lower: -2, Upper: -1, Count: 3, LowerInclusive: true, UpperInclusive: false, Index: 1},
{Lower: -4, Upper: -2, Count: 1, LowerInclusive: true, UpperInclusive: false, Index: 2},
{Lower: -8, Upper: -4, Count: 2, LowerInclusive: true, UpperInclusive: false, Index: 3},
{Lower: -16, Upper: -8, Count: 1, LowerInclusive: true, UpperInclusive: false, Index: 4},
{Lower: -64, Upper: -32, Count: 1, LowerInclusive: true, UpperInclusive: false, Index: 6},
},
},
{
histogram: Histogram{
Schema: 3,
PositiveSpans: []Span{
{Offset: -5, Length: 2}, // -5 -4
{Offset: 2, Length: 3}, // -1 0 1
{Offset: 2, Length: 2}, // 4 5
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 3},
},
expectedPositiveBuckets: []Bucket[uint64]{
{Lower: 0.5946035575013605, Upper: 0.6484197773255048, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: -5},
{Lower: 0.6484197773255048, Upper: 0.7071067811865475, Count: 3, LowerInclusive: false, UpperInclusive: true, Index: -4},
{Lower: 0.8408964152537144, Upper: 0.9170040432046711, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: -1},
{Lower: 0.9170040432046711, Upper: 1, Count: 2, LowerInclusive: false, UpperInclusive: true, Index: 0},
{Lower: 1, Upper: 1.0905077326652577, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 1},
{Lower: 1.2968395546510096, Upper: 1.414213562373095, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 4},
{Lower: 1.414213562373095, Upper: 1.5422108254079407, Count: 4, LowerInclusive: false, UpperInclusive: true, Index: 5},
},
expectedNegativeBuckets: []Bucket[uint64]{},
},
{
histogram: Histogram{
Schema: -2,
PositiveSpans: []Span{
{Offset: -2, Length: 4}, // -2 -1 0 1
{Offset: 2, Length: 2}, // 4 5
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0},
},
expectedPositiveBuckets: []Bucket[uint64]{
{Lower: 0.000244140625, Upper: 0.00390625, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: -2},
{Lower: 0.00390625, Upper: 0.0625, Count: 3, LowerInclusive: false, UpperInclusive: true, Index: -1},
{Lower: 0.0625, Upper: 1, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 0},
{Lower: 1, Upper: 16, Count: 2, LowerInclusive: false, UpperInclusive: true, Index: 1},
{Lower: 4096, Upper: 65536, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 4},
{Lower: 65536, Upper: 1048576, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 5},
},
expectedNegativeBuckets: []Bucket[uint64]{},
},
{
histogram: Histogram{
Schema: -1,
PositiveSpans: []Span{
{Offset: -2, Length: 5}, // -2 -1 0 1 2
},
PositiveBuckets: []int64{1, 2, -2, 1, -1},
},
expectedPositiveBuckets: []Bucket[uint64]{
{Lower: 0.015625, Upper: 0.0625, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: -2},
{Lower: 0.0625, Upper: 0.25, Count: 3, LowerInclusive: false, UpperInclusive: true, Index: -1},
{Lower: 0.25, Upper: 1, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 0},
{Lower: 1, Upper: 4, Count: 2, LowerInclusive: false, UpperInclusive: true, Index: 1},
{Lower: 4, Upper: 16, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 2},
},
expectedNegativeBuckets: []Bucket[uint64]{},
},
{
histogram: Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
CustomValues: []float64{5, 10, 20, 50},
},
expectedPositiveBuckets: []Bucket[uint64]{
{Lower: math.Inf(-1), Upper: 5, Count: 1, LowerInclusive: true, UpperInclusive: true, Index: 0},
{Lower: 5, Upper: 10, Count: 2, LowerInclusive: false, UpperInclusive: true, Index: 1},
{Lower: 20, Upper: 50, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 3},
{Lower: 50, Upper: math.Inf(1), Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 4},
},
expectedNegativeBuckets: []Bucket[uint64]{},
},
{
histogram: Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
CustomValues: []float64{0, 10, 20, 50},
},
expectedPositiveBuckets: []Bucket[uint64]{
{Lower: math.Inf(-1), Upper: 0, Count: 1, LowerInclusive: true, UpperInclusive: true, Index: 0},
{Lower: 0, Upper: 10, Count: 2, LowerInclusive: false, UpperInclusive: true, Index: 1},
{Lower: 20, Upper: 50, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 3},
{Lower: 50, Upper: math.Inf(1), Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 4},
},
expectedNegativeBuckets: []Bucket[uint64]{},
},
{
histogram: Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{
{Offset: 0, Length: 5},
},
PositiveBuckets: []int64{1, 1, 0, -1, 0},
CustomValues: []float64{-5, 0, 20, 50},
},
expectedPositiveBuckets: []Bucket[uint64]{
{Lower: math.Inf(-1), Upper: -5, Count: 1, LowerInclusive: true, UpperInclusive: true, Index: 0},
{Lower: -5, Upper: 0, Count: 2, LowerInclusive: false, UpperInclusive: true, Index: 1},
{Lower: 0, Upper: 20, Count: 2, LowerInclusive: false, UpperInclusive: true, Index: 2},
{Lower: 20, Upper: 50, Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 3},
{Lower: 50, Upper: math.Inf(1), Count: 1, LowerInclusive: false, UpperInclusive: true, Index: 4},
},
expectedNegativeBuckets: []Bucket[uint64]{},
},
}
for i, c := range cases {
t.Run(strconv.Itoa(i), func(t *testing.T) {
it := c.histogram.PositiveBucketIterator()
actualPositiveBuckets := make([]Bucket[uint64], 0, len(c.expectedPositiveBuckets))
for it.Next() {
actualPositiveBuckets = append(actualPositiveBuckets, it.At())
}
require.Equal(t, c.expectedPositiveBuckets, actualPositiveBuckets)
it = c.histogram.NegativeBucketIterator()
actualNegativeBuckets := make([]Bucket[uint64], 0, len(c.expectedNegativeBuckets))
for it.Next() {
actualNegativeBuckets = append(actualNegativeBuckets, it.At())
}
require.Equal(t, c.expectedNegativeBuckets, actualNegativeBuckets)
})
}
}
func TestHistogramToFloat(t *testing.T) {
h := Histogram{
Schema: 3,
Count: 61,
Sum: 2.7,
ZeroThreshold: 0.1,
ZeroCount: 42,
PositiveSpans: []Span{
{Offset: 0, Length: 4},
{Offset: 0, Length: 0},
{Offset: 0, Length: 3},
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 0},
NegativeSpans: []Span{
{Offset: 0, Length: 5},
{Offset: 1, Length: 0},
{Offset: 0, Length: 1},
},
NegativeBuckets: []int64{1, 2, -2, 1, -1, 0},
}
cases := []struct {
name string
fh *FloatHistogram
}{
{name: "without prior float histogram"},
{name: "prior float histogram with more buckets", fh: &FloatHistogram{
Schema: 2,
Count: 3,
Sum: 5,
ZeroThreshold: 4,
ZeroCount: 1,
PositiveSpans: []Span{
{Offset: 1, Length: 2},
{Offset: 1, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []float64{1, 2, 3, 4, 5, 6, 7, 8, 9},
NegativeSpans: []Span{
{Offset: 20, Length: 6},
{Offset: 12, Length: 7},
{Offset: 33, Length: 10},
},
NegativeBuckets: []float64{1, 2, 3, 4, 5, 6, 7, 8, 9},
}},
{name: "prior float histogram with fewer buckets", fh: &FloatHistogram{
Schema: 2,
Count: 3,
Sum: 5,
ZeroThreshold: 4,
ZeroCount: 1,
PositiveSpans: []Span{
{Offset: 1, Length: 2},
{Offset: 1, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []float64{1, 2},
NegativeSpans: []Span{
{Offset: 20, Length: 6},
{Offset: 12, Length: 7},
{Offset: 33, Length: 10},
},
NegativeBuckets: []float64{1, 2},
}},
}
for _, c := range cases {
t.Run(c.name, func(t *testing.T) {
fh := h.ToFloat(c.fh)
require.Equal(t, h.String(), fh.String())
})
}
}
func TestCustomBucketsHistogramToFloat(t *testing.T) {
h := Histogram{
Schema: CustomBucketsSchema,
Count: 10,
Sum: 2.7,
PositiveSpans: []Span{
{Offset: 0, Length: 4},
{Offset: 0, Length: 0},
{Offset: 0, Length: 3},
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 0},
CustomValues: []float64{5, 10, 20, 50, 100, 500},
}
cases := []struct {
name string
fh *FloatHistogram
}{
{name: "without prior float histogram"},
{name: "prior float histogram with more buckets", fh: &FloatHistogram{
Schema: 2,
Count: 3,
Sum: 5,
ZeroThreshold: 4,
ZeroCount: 1,
PositiveSpans: []Span{
{Offset: 1, Length: 2},
{Offset: 1, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []float64{1, 2, 3, 4, 5, 6, 7, 8, 9},
NegativeSpans: []Span{
{Offset: 20, Length: 6},
{Offset: 12, Length: 7},
{Offset: 33, Length: 10},
},
NegativeBuckets: []float64{1, 2, 3, 4, 5, 6, 7, 8, 9},
}},
{name: "prior float histogram with fewer buckets", fh: &FloatHistogram{
Schema: 2,
Count: 3,
Sum: 5,
ZeroThreshold: 4,
ZeroCount: 1,
PositiveSpans: []Span{
{Offset: 1, Length: 2},
{Offset: 1, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []float64{1, 2},
NegativeSpans: []Span{
{Offset: 20, Length: 6},
{Offset: 12, Length: 7},
{Offset: 33, Length: 10},
},
NegativeBuckets: []float64{1, 2},
}},
}
require.NoError(t, h.Validate())
for _, c := range cases {
t.Run(c.name, func(t *testing.T) {
hStr := h.String()
fh := h.ToFloat(c.fh)
require.NoError(t, fh.Validate())
require.Equal(t, hStr, h.String())
require.Equal(t, hStr, fh.String())
})
}
}
// TestHistogramEquals tests both Histogram and FloatHistogram.
func TestHistogramEquals(t *testing.T) {
h1 := Histogram{
Schema: 3,
Count: 62,
Sum: 2.7,
ZeroThreshold: 0.1,
ZeroCount: 42,
PositiveSpans: []Span{
{Offset: 0, Length: 4},
{Offset: 10, Length: 3},
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 0},
NegativeSpans: []Span{
{Offset: 0, Length: 4},
{Offset: 10, Length: 3},
},
NegativeBuckets: []int64{1, 2, -2, 1, -1, 0, 0},
}
equals := func(h1, h2 Histogram) {
require.True(t, h1.Equals(&h2))
require.True(t, h2.Equals(&h1))
h1f, h2f := h1.ToFloat(nil), h2.ToFloat(nil)
require.True(t, h1f.Equals(h2f))
require.True(t, h2f.Equals(h1f))
}
notEquals := func(h1, h2 Histogram) {
require.False(t, h1.Equals(&h2))
require.False(t, h2.Equals(&h1))
h1f, h2f := h1.ToFloat(nil), h2.ToFloat(nil)
require.False(t, h1f.Equals(h2f))
require.False(t, h2f.Equals(h1f))
}
notEqualsUntilFloatConv := func(h1, h2 Histogram) {
require.False(t, h1.Equals(&h2))
require.False(t, h2.Equals(&h1))
h1f, h2f := h1.ToFloat(nil), h2.ToFloat(nil)
require.True(t, h1f.Equals(h2f))
require.True(t, h2f.Equals(h1f))
}
require.NoError(t, h1.Validate())
h2 := h1.Copy()
equals(h1, *h2)
// Changed spans but same layout.
h2.PositiveSpans = append(h2.PositiveSpans, Span{Offset: 5})
h2.NegativeSpans = append(h2.NegativeSpans, Span{Offset: 2})
equals(h1, *h2)
// Adding empty spans in between.
h2.PositiveSpans[1].Offset = 6
h2.PositiveSpans = []Span{
h2.PositiveSpans[0],
{Offset: 1},
{Offset: 3},
h2.PositiveSpans[1],
h2.PositiveSpans[2],
}
h2.NegativeSpans[1].Offset = 5
h2.NegativeSpans = []Span{
h2.NegativeSpans[0],
{Offset: 2},
{Offset: 3},
h2.NegativeSpans[1],
h2.NegativeSpans[2],
}
equals(h1, *h2)
// All mismatches.
notEquals(h1, Histogram{})
h2.Schema = 1
notEquals(h1, *h2)
h2 = h1.Copy()
h2.Count++
notEquals(h1, *h2)
h2 = h1.Copy()
h2.Sum++
notEquals(h1, *h2)
h2 = h1.Copy()
h2.ZeroThreshold++
notEquals(h1, *h2)
h2 = h1.Copy()
h2.ZeroCount++
notEquals(h1, *h2)
// Changing value of buckets.
h2 = h1.Copy()
h2.PositiveBuckets[len(h2.PositiveBuckets)-1]++
notEquals(h1, *h2)
h2 = h1.Copy()
h2.NegativeBuckets[len(h2.NegativeBuckets)-1]++
notEquals(h1, *h2)
// Changing bucket layout.
h2 = h1.Copy()
h2.PositiveSpans[1].Offset++
notEquals(h1, *h2)
h2 = h1.Copy()
h2.NegativeSpans[1].Offset++
notEquals(h1, *h2)
// Adding an empty bucket.
h2 = h1.Copy()
h2.PositiveSpans[0].Offset--
h2.PositiveSpans[0].Length++
h2.PositiveBuckets = append([]int64{0}, h2.PositiveBuckets...)
notEquals(h1, *h2)
h2 = h1.Copy()
h2.NegativeSpans[0].Offset--
h2.NegativeSpans[0].Length++
h2.NegativeBuckets = append([]int64{0}, h2.NegativeBuckets...)
notEquals(h1, *h2)
// Adding new bucket.
h2 = h1.Copy()
h2.PositiveSpans = append(h2.PositiveSpans, Span{
Offset: 1,
Length: 1,
})
h2.PositiveBuckets = append(h2.PositiveBuckets, 1)
notEquals(h1, *h2)
h2 = h1.Copy()
h2.NegativeSpans = append(h2.NegativeSpans, Span{
Offset: 1,
Length: 1,
})
h2.NegativeBuckets = append(h2.NegativeBuckets, 1)
notEquals(h1, *h2)
// Sum is StaleNaN.
hStale := h1.Copy()
hStale.Sum = math.Float64frombits(value.StaleNaN)
notEquals(h1, *hStale)
equals(*hStale, *hStale)
// Sum is NaN (but not a StaleNaN).
hNaN := h1.Copy()
hNaN.Sum = math.NaN()
notEquals(h1, *hNaN)
equals(*hNaN, *hNaN)
// Sum StaleNaN vs regular NaN.
notEquals(*hStale, *hNaN)
// Has non-empty custom bounds for exponential schema.
hCustom := h1.Copy()
hCustom.CustomValues = []float64{1, 2, 3}
equals(h1, *hCustom)
cbh1 := Histogram{
Schema: CustomBucketsSchema,
Count: 10,
Sum: 2.7,
PositiveSpans: []Span{
{Offset: 0, Length: 4},
{Offset: 10, Length: 3},
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 0},
CustomValues: []float64{0.1, 0.2, 0.5, 1, 2, 5, 10, 15, 20, 25, 50, 75, 100, 200, 250, 500, 1000},
}
require.NoError(t, cbh1.Validate())
cbh2 := cbh1.Copy()
equals(cbh1, *cbh2)
// Has different custom bounds for custom buckets schema.
cbh2 = cbh1.Copy()
cbh2.CustomValues = []float64{0.1, 0.2, 0.5}
notEquals(cbh1, *cbh2)
// Has non-empty negative spans and buckets for custom buckets schema.
cbh2 = cbh1.Copy()
cbh2.NegativeSpans = []Span{{Offset: 0, Length: 1}}
cbh2.NegativeBuckets = []int64{1}
notEqualsUntilFloatConv(cbh1, *cbh2)
// Has non-zero zero count and threshold for custom buckets schema.
cbh2 = cbh1.Copy()
cbh2.ZeroThreshold = 0.1
cbh2.ZeroCount = 10
notEqualsUntilFloatConv(cbh1, *cbh2)
}
func TestHistogramCopy(t *testing.T) {
cases := []struct {
name string
orig *Histogram
expected *Histogram
}{
{
name: "without buckets",
orig: &Histogram{},
expected: &Histogram{},
},
{
name: "with buckets",
orig: &Histogram{
PositiveSpans: []Span{{-2, 1}},
PositiveBuckets: []int64{1, 3, -3, 42},
NegativeSpans: []Span{{3, 2}},
NegativeBuckets: []int64{5, 3, 1.234e5, 1000},
},
expected: &Histogram{
PositiveSpans: []Span{{-2, 1}},
PositiveBuckets: []int64{1, 3, -3, 42},
NegativeSpans: []Span{{3, 2}},
NegativeBuckets: []int64{5, 3, 1.234e5, 1000},
},
},
{
name: "with empty buckets and non empty capacity",
orig: &Histogram{
PositiveSpans: make([]Span, 0, 1),
PositiveBuckets: make([]int64, 0, 1),
NegativeSpans: make([]Span, 0, 1),
NegativeBuckets: make([]int64, 0, 1),
},
expected: &Histogram{},
},
{
name: "with custom buckets",
orig: &Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 1}},
PositiveBuckets: []int64{1, 3, -3, 42},
CustomValues: []float64{5, 10, 15},
},
expected: &Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 1}},
PositiveBuckets: []int64{1, 3, -3, 42},
CustomValues: []float64{5, 10, 15},
},
},
}
for _, tcase := range cases {
t.Run(tcase.name, func(t *testing.T) {
hCopy := tcase.orig.Copy()
// Modify a primitive value in the original histogram.
tcase.orig.Sum++
require.Equal(t, tcase.expected, hCopy)
assertDeepCopyHSpans(t, tcase.orig, hCopy, tcase.expected)
})
}
}
func TestHistogramCopyTo(t *testing.T) {
cases := []struct {
name string
orig *Histogram
expected *Histogram
}{
{
name: "without buckets",
orig: &Histogram{},
expected: &Histogram{},
},
{
name: "with buckets",
orig: &Histogram{
PositiveSpans: []Span{{-2, 1}},
PositiveBuckets: []int64{1, 3, -3, 42},
NegativeSpans: []Span{{3, 2}},
NegativeBuckets: []int64{5, 3, 1.234e5, 1000},
},
expected: &Histogram{
PositiveSpans: []Span{{-2, 1}},
PositiveBuckets: []int64{1, 3, -3, 42},
NegativeSpans: []Span{{3, 2}},
NegativeBuckets: []int64{5, 3, 1.234e5, 1000},
},
},
{
name: "with empty buckets and non empty capacity",
orig: &Histogram{
PositiveSpans: make([]Span, 0, 1),
PositiveBuckets: make([]int64, 0, 1),
NegativeSpans: make([]Span, 0, 1),
NegativeBuckets: make([]int64, 0, 1),
},
expected: &Histogram{},
},
{
name: "with custom buckets",
orig: &Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 1}},
PositiveBuckets: []int64{1, 3, -3, 42},
CustomValues: []float64{5, 10, 15},
},
expected: &Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 1}},
PositiveBuckets: []int64{1, 3, -3, 42},
CustomValues: []float64{5, 10, 15},
},
},
}
for _, tcase := range cases {
t.Run(tcase.name, func(t *testing.T) {
hCopy := &Histogram{}
tcase.orig.CopyTo(hCopy)
// Modify a primitive value in the original histogram.
tcase.orig.Sum++
require.Equal(t, tcase.expected, hCopy)
assertDeepCopyHSpans(t, tcase.orig, hCopy, tcase.expected)
})
}
}
func assertDeepCopyHSpans(t *testing.T, orig, hCopy, expected *Histogram) {
// Do an in-place expansion of an original spans slice.
orig.PositiveSpans = expandSpans(orig.PositiveSpans)
orig.PositiveSpans[len(orig.PositiveSpans)-1] = Span{1, 2}
hCopy.PositiveSpans = expandSpans(hCopy.PositiveSpans)
expected.PositiveSpans = expandSpans(expected.PositiveSpans)
// Expand the copy spans and assert that modifying the original has not affected the copy.
require.Equal(t, expected, hCopy)
}
func expandSpans(spans []Span) []Span {
n := len(spans)
if cap(spans) > n {
spans = spans[:n+1]
} else {
spans = append(spans, Span{})
}
return spans
}
func TestHistogramCompact(t *testing.T) {
cases := []struct {
name string
in *Histogram
maxEmptyBuckets int
expected *Histogram
}{
{
"empty histogram",
&Histogram{},
0,
&Histogram{},
},
{
"nothing should happen",
&Histogram{
PositiveSpans: []Span{{-2, 1}, {2, 3}},
PositiveBuckets: []int64{1, 3, -3, 42},
NegativeSpans: []Span{{3, 2}, {3, 2}},
NegativeBuckets: []int64{5, 3, 1.234e5, 1000},
},
0,
&Histogram{
PositiveSpans: []Span{{-2, 1}, {2, 3}},
PositiveBuckets: []int64{1, 3, -3, 42},
NegativeSpans: []Span{{3, 2}, {3, 2}},
NegativeBuckets: []int64{5, 3, 1.234e5, 1000},
},
},
{
"eliminate zero offsets",
&Histogram{
PositiveSpans: []Span{{-2, 1}, {0, 3}, {0, 1}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
NegativeSpans: []Span{{0, 2}, {0, 2}, {2, 1}, {0, 1}},
NegativeBuckets: []int64{5, 3, 1.234e5, 1000, 3, 4},
},
0,
&Histogram{
PositiveSpans: []Span{{-2, 5}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
NegativeSpans: []Span{{0, 4}, {2, 2}},
NegativeBuckets: []int64{5, 3, 1.234e5, 1000, 3, 4},
},
},
{
"eliminate zero length",
&Histogram{
PositiveSpans: []Span{{-2, 2}, {2, 0}, {3, 3}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
NegativeSpans: []Span{{0, 2}, {0, 0}, {2, 0}, {1, 4}},
NegativeBuckets: []int64{5, 3, 1.234e5, 1000, 3, 4},
},
0,
&Histogram{
PositiveSpans: []Span{{-2, 2}, {5, 3}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 4}},
NegativeBuckets: []int64{5, 3, 1.234e5, 1000, 3, 4},
},
},
{
"eliminate multiple zero length spans",
&Histogram{
PositiveSpans: []Span{{-2, 2}, {2, 0}, {2, 0}, {2, 0}, {3, 3}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
},
0,
&Histogram{
PositiveSpans: []Span{{-2, 2}, {9, 3}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
},
},
{
"cut empty buckets at start or end",
&Histogram{
PositiveSpans: []Span{{-4, 4}, {5, 3}},
PositiveBuckets: []int64{0, 0, 1, 3, -3, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 5}},
NegativeBuckets: []int64{5, 3, -4, -2, 3, 4, -9},
},
0,
&Histogram{
PositiveSpans: []Span{{-2, 2}, {5, 3}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 4}},
NegativeBuckets: []int64{5, 3, -4, -2, 3, 4},
},
},
{
"cut empty buckets at start and end",
&Histogram{
PositiveSpans: []Span{{-4, 4}, {5, 6}},
PositiveBuckets: []int64{0, 0, 1, 3, -3, 42, 3, -46, 0, 0},
NegativeSpans: []Span{{-2, 4}, {3, 5}},
NegativeBuckets: []int64{0, 0, 5, 3, -4, -2, 3, 4, -9},
},
0,
&Histogram{
PositiveSpans: []Span{{-2, 2}, {5, 3}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 4}},
NegativeBuckets: []int64{5, 3, -4, -2, 3, 4},
},
},
{
"cut empty buckets at start or end of spans, even in the middle",
&Histogram{
PositiveSpans: []Span{{-4, 6}, {3, 6}},
PositiveBuckets: []int64{0, 0, 1, 3, -4, 0, 1, 42, 3, -46, 0, 0},
NegativeSpans: []Span{{0, 2}, {2, 6}},
NegativeBuckets: []int64{5, 3, -8, 4, -2, 3, 4, -9},
},
0,
&Histogram{
PositiveSpans: []Span{{-2, 2}, {5, 3}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 4}},
NegativeBuckets: []int64{5, 3, -4, -2, 3, 4},
},
},
{
"cut empty buckets at start or end but merge spans due to maxEmptyBuckets",
&Histogram{
PositiveSpans: []Span{{-4, 4}, {5, 3}},
PositiveBuckets: []int64{0, 0, 1, 3, -3, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 5}},
NegativeBuckets: []int64{5, 3, -4, -2, 3, 4, -9},
},
10,
&Histogram{
PositiveSpans: []Span{{-2, 10}},
PositiveBuckets: []int64{1, 3, -4, 0, 0, 0, 0, 1, 42, 3},
NegativeSpans: []Span{{0, 9}},
NegativeBuckets: []int64{5, 3, -8, 0, 0, 4, -2, 3, 4},
},
},
{
"cut empty buckets from the middle of a span",
&Histogram{
PositiveSpans: []Span{{-4, 6}, {3, 3}},
PositiveBuckets: []int64{0, 0, 1, -1, 0, 3, -2, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 5}},
NegativeBuckets: []int64{5, 3, -4, -2, -2, 3, 4},
},
0,
&Histogram{
PositiveSpans: []Span{{-2, 1}, {2, 1}, {3, 3}},
PositiveBuckets: []int64{1, 2, -2, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 2}, {1, 2}},
NegativeBuckets: []int64{5, 3, -4, -2, 1, 4},
},
},
{
"cut out a span containing only empty buckets",
&Histogram{
PositiveSpans: []Span{{-4, 3}, {2, 2}, {3, 4}},
PositiveBuckets: []int64{0, 0, 1, -1, 0, 3, -2, 42, 3},
},
0,
&Histogram{
PositiveSpans: []Span{{-2, 1}, {7, 4}},
PositiveBuckets: []int64{1, 2, -2, 42, 3},
},
},
{
"cut empty buckets from the middle of a span, avoiding some due to maxEmptyBuckets",
&Histogram{
PositiveSpans: []Span{{-4, 6}, {3, 3}},
PositiveBuckets: []int64{0, 0, 1, -1, 0, 3, -2, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 5}},
NegativeBuckets: []int64{5, 3, -4, -2, -2, 3, 4},
},
1,
&Histogram{
PositiveSpans: []Span{{-2, 1}, {2, 1}, {3, 3}},
PositiveBuckets: []int64{1, 2, -2, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 5}},
NegativeBuckets: []int64{5, 3, -4, -2, -2, 3, 4},
},
},
{
"avoiding all cutting of empty buckets from the middle of a chunk due to maxEmptyBuckets",
&Histogram{
PositiveSpans: []Span{{-4, 6}, {3, 3}},
PositiveBuckets: []int64{0, 0, 1, -1, 0, 3, -2, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 5}},
NegativeBuckets: []int64{5, 3, -4, -2, -2, 3, 4},
},
2,
&Histogram{
PositiveSpans: []Span{{-2, 4}, {3, 3}},
PositiveBuckets: []int64{1, -1, 0, 3, -2, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 5}},
NegativeBuckets: []int64{5, 3, -4, -2, -2, 3, 4},
},
},
{
"everything merged into one span due to maxEmptyBuckets",
&Histogram{
PositiveSpans: []Span{{-4, 6}, {3, 3}},
PositiveBuckets: []int64{0, 0, 1, -1, 0, 3, -2, 42, 3},
NegativeSpans: []Span{{0, 2}, {3, 5}},
NegativeBuckets: []int64{5, 3, -4, -2, -2, 3, 4},
},
3,
&Histogram{
PositiveSpans: []Span{{-2, 10}},
PositiveBuckets: []int64{1, -1, 0, 3, -3, 0, 0, 1, 42, 3},
NegativeSpans: []Span{{0, 10}},
NegativeBuckets: []int64{5, 3, -8, 0, 0, 4, -2, -2, 3, 4},
},
},
{
"only empty buckets and maxEmptyBuckets greater zero",
&Histogram{
PositiveSpans: []Span{{-4, 6}, {3, 3}},
PositiveBuckets: []int64{0, 0, 0, 0, 0, 0, 0, 0, 0},
NegativeSpans: []Span{{0, 7}},
NegativeBuckets: []int64{0, 0, 0, 0, 0, 0, 0},
},
3,
&Histogram{
PositiveSpans: []Span{},
PositiveBuckets: []int64{},
NegativeSpans: []Span{},
NegativeBuckets: []int64{},
},
},
{
"multiple spans of only empty buckets",
&Histogram{
PositiveSpans: []Span{{-10, 2}, {2, 1}, {3, 3}},
PositiveBuckets: []int64{0, 0, 0, 0, 2, 3},
NegativeSpans: []Span{{-10, 2}, {2, 1}, {3, 3}},
NegativeBuckets: []int64{2, 3, -5, 0, 0, 0},
},
0,
&Histogram{
PositiveSpans: []Span{{-1, 2}},
PositiveBuckets: []int64{2, 3},
NegativeSpans: []Span{{-10, 2}},
NegativeBuckets: []int64{2, 3},
},
},
{
"nothing should happen with custom buckets",
&Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 1}, {2, 3}},
PositiveBuckets: []int64{1, 3, -3, 42},
CustomValues: []float64{5, 10, 15},
},
0,
&Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 1}, {2, 3}},
PositiveBuckets: []int64{1, 3, -3, 42},
CustomValues: []float64{5, 10, 15},
},
},
{
"eliminate zero offsets with custom buckets",
&Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 1}, {0, 3}, {0, 1}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
CustomValues: []float64{5, 10, 15, 20},
},
0,
&Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 5}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
CustomValues: []float64{5, 10, 15, 20},
},
},
{
"eliminate zero length with custom buckets",
&Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 2}, {2, 0}, {3, 3}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
CustomValues: []float64{5, 10, 15, 20},
},
0,
&Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 2}, {5, 3}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
CustomValues: []float64{5, 10, 15, 20},
},
},
{
"eliminate multiple zero length spans with custom buckets",
&Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 2}, {2, 0}, {2, 0}, {2, 0}, {3, 3}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
CustomValues: []float64{5, 10, 15, 20},
},
0,
&Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 2}, {9, 3}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
CustomValues: []float64{5, 10, 15, 20},
},
},
{
"cut empty buckets at start or end of spans, even in the middle, with custom buckets",
&Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-4, 6}, {3, 6}},
PositiveBuckets: []int64{0, 0, 1, 3, -4, 0, 1, 42, 3, -46, 0, 0},
CustomValues: []float64{5, 10, 15, 20},
},
0,
&Histogram{
Schema: CustomBucketsSchema,
PositiveSpans: []Span{{-2, 2}, {5, 3}},
PositiveBuckets: []int64{1, 3, -3, 42, 3},
CustomValues: []float64{5, 10, 15, 20},
},
},
}
for _, c := range cases {
t.Run(c.name, func(t *testing.T) {
require.Equal(t, c.expected, c.in.Compact(c.maxEmptyBuckets))
// Compact has happened in-place, too.
require.Equal(t, c.expected, c.in)
})
}
}
func TestHistogramValidation(t *testing.T) {
tests := map[string]struct {
h *Histogram
errMsg string
skipFloat bool
}{
"valid histogram": {
h: &Histogram{
Count: 12,
ZeroCount: 2,
ZeroThreshold: 0.001,
Sum: 19.4,
Schema: 1,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
NegativeSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
NegativeBuckets: []int64{1, 1, -1, 0},
},
},
"valid histogram with NaN observations that has its Count (4) higher than the actual total of buckets (2 + 1)": {
// This case is possible if NaN values (which do not fall into any bucket) are observed.
h: &Histogram{
ZeroCount: 2,
Count: 4,
Sum: math.NaN(),
PositiveSpans: []Span{{Offset: 0, Length: 1}},
PositiveBuckets: []int64{1},
},
},
"rejects histogram without NaN observations that has its Count (4) higher than the actual total of buckets (2 + 1)": {
h: &Histogram{
ZeroCount: 2,
Count: 4,
Sum: 333,
PositiveSpans: []Span{{Offset: 0, Length: 1}},
PositiveBuckets: []int64{1},
},
errMsg: `3 observations found in buckets, but the Count field is 4: histogram's observation count should equal the number of observations found in the buckets (in absence of NaN)`,
skipFloat: true,
},
"rejects histogram that has too few negative buckets": {
h: &Histogram{
NegativeSpans: []Span{{Offset: 0, Length: 1}},
NegativeBuckets: []int64{},
},
errMsg: `negative side: spans need 1 buckets, have 0 buckets: histogram spans specify different number of buckets than provided`,
},
"rejects histogram that has too few positive buckets": {
h: &Histogram{
PositiveSpans: []Span{{Offset: 0, Length: 1}},
PositiveBuckets: []int64{},
},
errMsg: `positive side: spans need 1 buckets, have 0 buckets: histogram spans specify different number of buckets than provided`,
},
"rejects histogram that has too many negative buckets": {
h: &Histogram{
NegativeSpans: []Span{{Offset: 0, Length: 1}},
NegativeBuckets: []int64{1, 2},
},
errMsg: `negative side: spans need 1 buckets, have 2 buckets: histogram spans specify different number of buckets than provided`,
},
"rejects histogram that has too many positive buckets": {
h: &Histogram{
PositiveSpans: []Span{{Offset: 0, Length: 1}},
PositiveBuckets: []int64{1, 2},
},
errMsg: `positive side: spans need 1 buckets, have 2 buckets: histogram spans specify different number of buckets than provided`,
},
"rejects a histogram that has a negative span with a negative offset": {
h: &Histogram{
NegativeSpans: []Span{{Offset: -1, Length: 1}, {Offset: -1, Length: 1}},
NegativeBuckets: []int64{1, 2},
},
errMsg: `negative side: span number 2 with offset -1: histogram has a span whose offset is negative`,
},
"rejects a histogram which has a positive span with a negative offset": {
h: &Histogram{
PositiveSpans: []Span{{Offset: -1, Length: 1}, {Offset: -1, Length: 1}},
PositiveBuckets: []int64{1, 2},
},
errMsg: `positive side: span number 2 with offset -1: histogram has a span whose offset is negative`,
},
"rejects a histogram that has a negative bucket with a negative count": {
h: &Histogram{
NegativeSpans: []Span{{Offset: -1, Length: 1}},
NegativeBuckets: []int64{-1},
},
errMsg: `negative side: bucket number 1 has observation count of -1: histogram has a bucket whose observation count is negative`,
},
"rejects a histogram that has a positive bucket with a negative count": {
h: &Histogram{
PositiveSpans: []Span{{Offset: -1, Length: 1}},
PositiveBuckets: []int64{-1},
},
errMsg: `positive side: bucket number 1 has observation count of -1: histogram has a bucket whose observation count is negative`,
},
"rejects a histogram that has a lower count than count in buckets": {
h: &Histogram{
Count: 0,
NegativeSpans: []Span{{Offset: -1, Length: 1}},
PositiveSpans: []Span{{Offset: -1, Length: 1}},
NegativeBuckets: []int64{1},
PositiveBuckets: []int64{1},
},
errMsg: `2 observations found in buckets, but the Count field is 0: histogram's observation count should equal the number of observations found in the buckets (in absence of NaN)`,
skipFloat: true,
},
"rejects a histogram that doesn't count the zero bucket in its count": {
h: &Histogram{
Count: 2,
ZeroCount: 1,
NegativeSpans: []Span{{Offset: -1, Length: 1}},
PositiveSpans: []Span{{Offset: -1, Length: 1}},
NegativeBuckets: []int64{1},
PositiveBuckets: []int64{1},
},
errMsg: `3 observations found in buckets, but the Count field is 2: histogram's observation count should equal the number of observations found in the buckets (in absence of NaN)`,
skipFloat: true,
},
"rejects an exponential histogram with custom buckets schema": {
h: &Histogram{
Count: 12,
ZeroCount: 2,
ZeroThreshold: 0.001,
Sum: 19.4,
Schema: CustomBucketsSchema,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
NegativeSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
NegativeBuckets: []int64{1, 1, -1, 0},
},
errMsg: `custom buckets: only 0 custom bounds defined which is insufficient to cover total span length of 5: histogram custom bounds are too few`,
},
"rejects a custom buckets histogram with exponential schema": {
h: &Histogram{
Count: 5,
Sum: 19.4,
Schema: 0,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
CustomValues: []float64{1, 2, 3, 4},
},
errMsg: `histogram with exponential schema must not have custom bounds`,
skipFloat: true, // Converting to float will remove the wrong fields so only the float version will pass validation
},
"rejects a custom buckets histogram with zero/negative buckets": {
h: &Histogram{
Count: 12,
ZeroCount: 2,
ZeroThreshold: 0.001,
Sum: 19.4,
Schema: CustomBucketsSchema,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
NegativeSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
NegativeBuckets: []int64{1, 1, -1, 0},
CustomValues: []float64{1, 2, 3, 4},
},
errMsg: `custom buckets: must have zero count of 0`,
skipFloat: true, // Converting to float will remove the wrong fields so only the float version will pass validation
},
"rejects a custom buckets histogram with negative offset in first span": {
h: &Histogram{
Count: 5,
Sum: 19.4,
Schema: CustomBucketsSchema,
PositiveSpans: []Span{
{Offset: -1, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
CustomValues: []float64{1, 2, 3, 4},
},
errMsg: `custom buckets: span number 1 with offset -1: histogram has a span whose offset is negative`,
},
"rejects a custom buckets histogram with negative offset in subsequent spans": {
h: &Histogram{
Count: 5,
Sum: 19.4,
Schema: CustomBucketsSchema,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: -1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
CustomValues: []float64{1, 2, 3, 4},
},
errMsg: `custom buckets: span number 2 with offset -1: histogram has a span whose offset is negative`,
},
"rejects a custom buckets histogram with non-matching bucket counts": {
h: &Histogram{
Count: 5,
Sum: 19.4,
Schema: CustomBucketsSchema,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1},
CustomValues: []float64{1, 2, 3, 4},
},
errMsg: `custom buckets: spans need 4 buckets, have 3 buckets: histogram spans specify different number of buckets than provided`,
},
"rejects a custom buckets histogram with too few bounds": {
h: &Histogram{
Count: 5,
Sum: 19.4,
Schema: CustomBucketsSchema,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
CustomValues: []float64{1, 2, 3},
},
errMsg: `custom buckets: only 3 custom bounds defined which is insufficient to cover total span length of 5: histogram custom bounds are too few`,
},
"valid custom buckets histogram": {
h: &Histogram{
Count: 5,
Sum: 19.4,
Schema: CustomBucketsSchema,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
CustomValues: []float64{1, 2, 3, 4},
},
},
"valid custom buckets histogram with extra bounds": {
h: &Histogram{
Count: 5,
Sum: 19.4,
Schema: CustomBucketsSchema,
PositiveSpans: []Span{
{Offset: 0, Length: 2},
{Offset: 1, Length: 2},
},
PositiveBuckets: []int64{1, 1, -1, 0},
CustomValues: []float64{1, 2, 3, 4, 5, 6, 7, 8},
},
},
}
for testName, tc := range tests {
t.Run(testName, func(t *testing.T) {
if err := tc.h.Validate(); tc.errMsg != "" {
require.EqualError(t, err, tc.errMsg)
} else {
require.NoError(t, err)
}
if tc.skipFloat {
return
}
fh := tc.h.ToFloat(nil)
if err := fh.Validate(); tc.errMsg != "" {
require.EqualError(t, err, tc.errMsg)
} else {
require.NoError(t, err)
}
})
}
}
func BenchmarkHistogramValidation(b *testing.B) {
histograms := GenerateBigTestHistograms(b.N, 500)
b.ResetTimer()
for _, h := range histograms {
require.NoError(b, h.Validate())
}
}
func TestHistogramReduceResolution(t *testing.T) {
tcs := map[string]struct {
origin *Histogram
target *Histogram
}{
"valid histogram": {
origin: &Histogram{
Schema: 0,
PositiveSpans: []Span{
{Offset: 0, Length: 4},
{Offset: 0, Length: 0},
{Offset: 3, Length: 2},
},
PositiveBuckets: []int64{1, 2, -2, 1, -1, 0},
NegativeSpans: []Span{
{Offset: 0, Length: 4},
{Offset: 0, Length: 0},
{Offset: 3, Length: 2},
},
NegativeBuckets: []int64{1, 2, -2, 1, -1, 0},
},
target: &Histogram{
Schema: -1,
PositiveSpans: []Span{
{Offset: 0, Length: 3},
{Offset: 1, Length: 1},
},
PositiveBuckets: []int64{1, 3, -2, 0},
NegativeSpans: []Span{
{Offset: 0, Length: 3},
{Offset: 1, Length: 1},
},
NegativeBuckets: []int64{1, 3, -2, 0},
},
},
}
for _, tc := range tcs {
target := tc.origin.ReduceResolution(tc.target.Schema)
require.Equal(t, tc.target, target)
// Check that receiver histogram was mutated:
require.Equal(t, tc.target, tc.origin)
}
}