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mirror of https://github.com/golang/go synced 2024-11-17 15:14:42 -07:00

cmd/trace: factor out durationHistogram

This code will be useful for the new tracer, and there's no need to
duplicate it. This change copies it to internal/trace/traceviewer, adds
some comments, and renames it to TimeHistogram.

While we're here, let's get rid of the unused String method which has a
comment talking about how awful the rendering is.

Also, let's get rid of uses of niceDuration. We'd have to bring it
with us in the move and I don't think it's worth it. The difference
between the default time.Duration rendering and the niceDuration
rendering is usually a few extra digits of precision. Yes, it's noisier,
but AFAICT it's not substantially worse. It doesn't seem worth the new
API, even if it's just internal. We can also always bring it back later.

For #60773.
For #63960.

Change-Id: I795f58f579f1d503c540c3a40bed12e52bce38e2
Reviewed-on: https://go-review.googlesource.com/c/go/+/542001
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
This commit is contained in:
Michael Anthony Knyszek 2023-11-14 06:19:07 +00:00 committed by Michael Knyszek
parent 816ee0be38
commit 7e32d8d10b
3 changed files with 94 additions and 121 deletions

View File

@ -9,8 +9,8 @@ import (
"fmt"
"html/template"
"internal/trace"
"internal/trace/traceviewer"
"log"
"math"
"net/http"
"net/url"
"reflect"
@ -808,122 +808,9 @@ func newRegionFilter(r *http.Request) (*regionFilter, error) {
}, nil
}
type durationHistogram struct {
Count int
Buckets []int
MinBucket, MaxBucket int
}
// Five buckets for every power of 10.
var logDiv = math.Log(math.Pow(10, 1.0/5))
func (h *durationHistogram) add(d time.Duration) {
var bucket int
if d > 0 {
bucket = int(math.Log(float64(d)) / logDiv)
}
if len(h.Buckets) <= bucket {
h.Buckets = append(h.Buckets, make([]int, bucket-len(h.Buckets)+1)...)
h.Buckets = h.Buckets[:cap(h.Buckets)]
}
h.Buckets[bucket]++
if bucket < h.MinBucket || h.MaxBucket == 0 {
h.MinBucket = bucket
}
if bucket > h.MaxBucket {
h.MaxBucket = bucket
}
h.Count++
}
func (h *durationHistogram) BucketMin(bucket int) time.Duration {
return time.Duration(math.Exp(float64(bucket) * logDiv))
}
func niceDuration(d time.Duration) string {
var rnd time.Duration
var unit string
switch {
case d < 10*time.Microsecond:
rnd, unit = time.Nanosecond, "ns"
case d < 10*time.Millisecond:
rnd, unit = time.Microsecond, "µs"
case d < 10*time.Second:
rnd, unit = time.Millisecond, "ms"
default:
rnd, unit = time.Second, "s "
}
return fmt.Sprintf("%d%s", d/rnd, unit)
}
func (h *durationHistogram) ToHTML(urlmaker func(min, max time.Duration) string) template.HTML {
if h == nil || h.Count == 0 {
return template.HTML("")
}
const barWidth = 400
maxCount := 0
for _, count := range h.Buckets {
if count > maxCount {
maxCount = count
}
}
w := new(strings.Builder)
fmt.Fprintf(w, `<table>`)
for i := h.MinBucket; i <= h.MaxBucket; i++ {
// Tick label.
if h.Buckets[i] > 0 {
fmt.Fprintf(w, `<tr><td class="histoTime" align="right"><a href=%s>%s</a></td>`, urlmaker(h.BucketMin(i), h.BucketMin(i+1)), niceDuration(h.BucketMin(i)))
} else {
fmt.Fprintf(w, `<tr><td class="histoTime" align="right">%s</td>`, niceDuration(h.BucketMin(i)))
}
// Bucket bar.
width := h.Buckets[i] * barWidth / maxCount
fmt.Fprintf(w, `<td><div style="width:%dpx;background:blue;position:relative">&nbsp;</div></td>`, width)
// Bucket count.
fmt.Fprintf(w, `<td align="right"><div style="position:relative">%d</div></td>`, h.Buckets[i])
fmt.Fprintf(w, "</tr>\n")
}
// Final tick label.
fmt.Fprintf(w, `<tr><td align="right">%s</td></tr>`, niceDuration(h.BucketMin(h.MaxBucket+1)))
fmt.Fprintf(w, `</table>`)
return template.HTML(w.String())
}
func (h *durationHistogram) String() string {
const barWidth = 40
labels := []string{}
maxLabel := 0
maxCount := 0
for i := h.MinBucket; i <= h.MaxBucket; i++ {
// TODO: This formatting is pretty awful.
label := fmt.Sprintf("[%-12s%-11s)", h.BucketMin(i).String()+",", h.BucketMin(i+1))
labels = append(labels, label)
if len(label) > maxLabel {
maxLabel = len(label)
}
count := h.Buckets[i]
if count > maxCount {
maxCount = count
}
}
w := new(strings.Builder)
for i := h.MinBucket; i <= h.MaxBucket; i++ {
count := h.Buckets[i]
bar := count * barWidth / maxCount
fmt.Fprintf(w, "%*s %-*s %d\n", maxLabel, labels[i-h.MinBucket], barWidth, strings.Repeat("█", bar), count)
}
return w.String()
}
type regionStats struct {
regionTypeID
Histogram durationHistogram
Histogram traceviewer.TimeHistogram
}
func (s *regionStats) UserRegionURL() func(min, max time.Duration) string {
@ -933,7 +820,7 @@ func (s *regionStats) UserRegionURL() func(min, max time.Duration) string {
}
func (s *regionStats) add(region regionDesc) {
s.Histogram.add(region.duration())
s.Histogram.Add(region.duration())
}
var templUserRegionTypes = template.Must(template.New("").Parse(`
@ -966,8 +853,8 @@ var templUserRegionTypes = template.Must(template.New("").Parse(`
type taskStats struct {
Type string
Count int // Complete + incomplete tasks
Histogram durationHistogram // Complete tasks only
Count int // Complete + incomplete tasks
Histogram traceviewer.TimeHistogram // Complete tasks only
}
func (s *taskStats) UserTaskURL(complete bool) func(min, max time.Duration) string {
@ -979,7 +866,7 @@ func (s *taskStats) UserTaskURL(complete bool) func(min, max time.Duration) stri
func (s *taskStats) add(task *taskDesc) {
s.Count++
if task.complete() {
s.Histogram.add(task.duration())
s.Histogram.Add(task.duration())
}
}
@ -1169,7 +1056,7 @@ func isUserAnnotationEvent(ev *trace.Event) (taskID uint64, ok bool) {
var templUserRegionType = template.Must(template.New("").Funcs(template.FuncMap{
"prettyDuration": func(nsec int64) template.HTML {
d := time.Duration(nsec) * time.Nanosecond
return template.HTML(niceDuration(d))
return template.HTML(d.String())
},
"percent": func(dividend, divisor int64) template.HTML {
if divisor == 0 {

View File

@ -169,7 +169,7 @@ func httpGoroutine(w http.ResponseWriter, r *http.Request) {
var templGoroutine = template.Must(template.New("").Funcs(template.FuncMap{
"prettyDuration": func(nsec int64) template.HTML {
d := time.Duration(nsec) * time.Nanosecond
return template.HTML(niceDuration(d))
return template.HTML(d.String())
},
"percent": func(dividend, divisor int64) template.HTML {
if divisor == 0 {

View File

@ -0,0 +1,86 @@
// Copyright 2023 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 traceviewer
import (
"fmt"
"html/template"
"math"
"strings"
"time"
)
// TimeHistogram is an high-dynamic-range histogram for durations.
type TimeHistogram struct {
Count int
Buckets []int
MinBucket, MaxBucket int
}
// Five buckets for every power of 10.
var logDiv = math.Log(math.Pow(10, 1.0/5))
// Add adds a single sample to the histogram.
func (h *TimeHistogram) Add(d time.Duration) {
var bucket int
if d > 0 {
bucket = int(math.Log(float64(d)) / logDiv)
}
if len(h.Buckets) <= bucket {
h.Buckets = append(h.Buckets, make([]int, bucket-len(h.Buckets)+1)...)
h.Buckets = h.Buckets[:cap(h.Buckets)]
}
h.Buckets[bucket]++
if bucket < h.MinBucket || h.MaxBucket == 0 {
h.MinBucket = bucket
}
if bucket > h.MaxBucket {
h.MaxBucket = bucket
}
h.Count++
}
// BucketMin returns the minimum duration value for a provided bucket.
func (h *TimeHistogram) BucketMin(bucket int) time.Duration {
return time.Duration(math.Exp(float64(bucket) * logDiv))
}
// ToHTML renders the histogram as HTML.
func (h *TimeHistogram) ToHTML(urlmaker func(min, max time.Duration) string) template.HTML {
if h == nil || h.Count == 0 {
return template.HTML("")
}
const barWidth = 400
maxCount := 0
for _, count := range h.Buckets {
if count > maxCount {
maxCount = count
}
}
w := new(strings.Builder)
fmt.Fprintf(w, `<table>`)
for i := h.MinBucket; i <= h.MaxBucket; i++ {
// Tick label.
if h.Buckets[i] > 0 {
fmt.Fprintf(w, `<tr><td class="histoTime" align="right"><a href=%s>%s</a></td>`, urlmaker(h.BucketMin(i), h.BucketMin(i+1)), h.BucketMin(i))
} else {
fmt.Fprintf(w, `<tr><td class="histoTime" align="right">%s</td>`, h.BucketMin(i))
}
// Bucket bar.
width := h.Buckets[i] * barWidth / maxCount
fmt.Fprintf(w, `<td><div style="width:%dpx;background:blue;position:relative">&nbsp;</div></td>`, width)
// Bucket count.
fmt.Fprintf(w, `<td align="right"><div style="position:relative">%d</div></td>`, h.Buckets[i])
fmt.Fprintf(w, "</tr>\n")
}
// Final tick label.
fmt.Fprintf(w, `<tr><td align="right">%s</td></tr>`, h.BucketMin(h.MaxBucket+1))
fmt.Fprintf(w, `</table>`)
return template.HTML(w.String())
}