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
|
// Copyright 2020 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package runtime_test
import (
"math"
. "runtime"
"testing"
)
var dummyTimeHistogram TimeHistogram
func TestTimeHistogram(t *testing.T) {
// We need to use a global dummy because this
// could get stack-allocated with a non-8-byte alignment.
// The result of this bad alignment is a segfault on
// 32-bit platforms when calling Record.
h := &dummyTimeHistogram
// Record exactly one sample in each bucket.
for i := 0; i < TimeHistNumSuperBuckets; i++ {
var base int64
if i > 0 {
base = int64(1) << (i + TimeHistSubBucketBits - 1)
}
for j := 0; j < TimeHistNumSubBuckets; j++ {
v := int64(j)
if i > 0 {
v <<= i - 1
}
h.Record(base + v)
}
}
// Hit the underflow bucket.
h.Record(int64(-1))
// Check to make sure there's exactly one count in each
// bucket.
for i := uint(0); i < TimeHistNumSuperBuckets; i++ {
for j := uint(0); j < TimeHistNumSubBuckets; j++ {
c, ok := h.Count(i, j)
if !ok {
t.Errorf("hit underflow bucket unexpectedly: (%d, %d)", i, j)
} else if c != 1 {
t.Errorf("bucket (%d, %d) has count that is not 1: %d", i, j, c)
}
}
}
c, ok := h.Count(TimeHistNumSuperBuckets, 0)
if ok {
t.Errorf("expected to hit underflow bucket: (%d, %d)", TimeHistNumSuperBuckets, 0)
}
if c != 1 {
t.Errorf("underflow bucket has count that is not 1: %d", c)
}
// Check overflow behavior.
// By hitting a high value, we should just be adding into the highest bucket.
h.Record(math.MaxInt64)
c, ok = h.Count(TimeHistNumSuperBuckets-1, TimeHistNumSubBuckets-1)
if !ok {
t.Error("hit underflow bucket in highest bucket unexpectedly")
} else if c != 2 {
t.Errorf("highest has count that is not 2: %d", c)
}
dummyTimeHistogram = TimeHistogram{}
}
func TestTimeHistogramMetricsBuckets(t *testing.T) {
buckets := TimeHistogramMetricsBuckets()
nonInfBucketsLen := TimeHistNumSubBuckets * TimeHistNumSuperBuckets
expBucketsLen := nonInfBucketsLen + 2 // Count -Inf and +Inf.
if len(buckets) != expBucketsLen {
t.Fatalf("unexpected length of buckets: got %d, want %d", len(buckets), expBucketsLen)
}
// Check the first non-Inf 2*TimeHistNumSubBuckets buckets in order, skipping the
// first bucket which should be -Inf (checked later).
//
// Because of the way this scheme works, the bottom TimeHistNumSubBuckets
// buckets are fully populated, and then the next TimeHistNumSubBuckets
// have the TimeHistSubBucketBits'th bit set, while the bottom are once
// again fully populated.
for i := 1; i <= 2*TimeHistNumSubBuckets+1; i++ {
if got, want := buckets[i], float64(i-1)/1e9; got != want {
t.Errorf("expected bucket %d to have value %e, got %e", i, want, got)
}
}
// Check some values.
idxToBucket := map[int]float64{
0: math.Inf(-1),
33: float64(0x10<<1) / 1e9,
34: float64(0x11<<1) / 1e9,
49: float64(0x10<<2) / 1e9,
58: float64(0x19<<2) / 1e9,
65: float64(0x10<<3) / 1e9,
513: float64(0x10<<31) / 1e9,
519: float64(0x16<<31) / 1e9,
expBucketsLen - 2: float64(0x1f<<43) / 1e9,
expBucketsLen - 1: math.Inf(1),
}
for idx, bucket := range idxToBucket {
if got, want := buckets[idx], bucket; got != want {
t.Errorf("expected bucket %d to have value %e, got %e", idx, want, got)
}
}
}
|
