// Copyright 2014 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.
// Goroutine-related profiles.
package main
import (
"cmp"
"fmt"
"html/template"
"internal/trace"
"internal/trace/traceviewer"
"log"
"net/http"
"slices"
"sort"
"strings"
"time"
)
// GoroutinesHandlerFunc returns a HandlerFunc that serves list of goroutine groups.
func GoroutinesHandlerFunc(summaries map[trace.GoID]*trace.GoroutineSummary) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
// goroutineGroup describes a group of goroutines grouped by name.
type goroutineGroup struct {
Name string // Start function.
N int // Total number of goroutines in this group.
ExecTime time.Duration // Total execution time of all goroutines in this group.
}
// Accumulate groups by Name.
groupsByName := make(map[string]goroutineGroup)
for _, summary := range summaries {
group := groupsByName[summary.Name]
group.Name = summary.Name
group.N++
group.ExecTime += summary.ExecTime
groupsByName[summary.Name] = group
}
var groups []goroutineGroup
for _, group := range groupsByName {
groups = append(groups, group)
}
slices.SortFunc(groups, func(a, b goroutineGroup) int {
return cmp.Compare(b.ExecTime, a.ExecTime)
})
w.Header().Set("Content-Type", "text/html;charset=utf-8")
if err := templGoroutines.Execute(w, groups); err != nil {
log.Printf("failed to execute template: %v", err)
return
}
}
}
var templGoroutines = template.Must(template.New("").Parse(`
Goroutines
Below is a table of all goroutines in the trace grouped by start location and sorted by the total execution time of the group.
Click a start location to view more details about that group.
`))
// GoroutineHandler creates a handler that serves information about
// goroutines in a particular group.
func GoroutineHandler(summaries map[trace.GoID]*trace.GoroutineSummary) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
goroutineName := r.FormValue("name")
type goroutine struct {
*trace.GoroutineSummary
NonOverlappingStats map[string]time.Duration
HasRangeTime bool
}
// Collect all the goroutines in the group.
var (
goroutines []goroutine
name string
totalExecTime, execTime time.Duration
maxTotalTime time.Duration
)
validNonOverlappingStats := make(map[string]struct{})
validRangeStats := make(map[string]struct{})
for _, summary := range summaries {
totalExecTime += summary.ExecTime
if summary.Name != goroutineName {
continue
}
nonOverlappingStats := summary.NonOverlappingStats()
for name := range nonOverlappingStats {
validNonOverlappingStats[name] = struct{}{}
}
var totalRangeTime time.Duration
for name, dt := range summary.RangeTime {
validRangeStats[name] = struct{}{}
totalRangeTime += dt
}
goroutines = append(goroutines, goroutine{
GoroutineSummary: summary,
NonOverlappingStats: nonOverlappingStats,
HasRangeTime: totalRangeTime != 0,
})
name = summary.Name
execTime += summary.ExecTime
if maxTotalTime < summary.TotalTime {
maxTotalTime = summary.TotalTime
}
}
// Compute the percent of total execution time these goroutines represent.
execTimePercent := ""
if totalExecTime > 0 {
execTimePercent = fmt.Sprintf("%.2f%%", float64(execTime)/float64(totalExecTime)*100)
}
// Sort.
sortBy := r.FormValue("sortby")
if _, ok := validNonOverlappingStats[sortBy]; ok {
slices.SortFunc(goroutines, func(a, b goroutine) int {
return cmp.Compare(b.NonOverlappingStats[sortBy], a.NonOverlappingStats[sortBy])
})
} else {
// Sort by total time by default.
slices.SortFunc(goroutines, func(a, b goroutine) int {
return cmp.Compare(b.TotalTime, a.TotalTime)
})
}
// Write down all the non-overlapping stats and sort them.
allNonOverlappingStats := make([]string, 0, len(validNonOverlappingStats))
for name := range validNonOverlappingStats {
allNonOverlappingStats = append(allNonOverlappingStats, name)
}
slices.SortFunc(allNonOverlappingStats, func(a, b string) int {
if a == b {
return 0
}
if a == "Execution time" {
return -1
}
if b == "Execution time" {
return 1
}
return cmp.Compare(a, b)
})
// Write down all the range stats and sort them.
allRangeStats := make([]string, 0, len(validRangeStats))
for name := range validRangeStats {
allRangeStats = append(allRangeStats, name)
}
sort.Strings(allRangeStats)
err := templGoroutine.Execute(w, struct {
Name string
N int
ExecTimePercent string
MaxTotal time.Duration
Goroutines []goroutine
NonOverlappingStats []string
RangeStats []string
}{
Name: name,
N: len(goroutines),
ExecTimePercent: execTimePercent,
MaxTotal: maxTotalTime,
Goroutines: goroutines,
NonOverlappingStats: allNonOverlappingStats,
RangeStats: allRangeStats,
})
if err != nil {
http.Error(w, fmt.Sprintf("failed to execute template: %v", err), http.StatusInternalServerError)
return
}
}
}
func stat2Color(statName string) string {
color := "#636363"
if strings.HasPrefix(statName, "Block time") {
color = "#d01c8b"
}
switch statName {
case "Sched wait time":
color = "#2c7bb6"
case "Syscall execution time":
color = "#7b3294"
case "Execution time":
color = "#d7191c"
}
return color
}
var templGoroutine = template.Must(template.New("").Funcs(template.FuncMap{
"percent": func(dividend, divisor time.Duration) template.HTML {
if divisor == 0 {
return ""
}
return template.HTML(fmt.Sprintf("(%.1f%%)", float64(dividend)/float64(divisor)*100))
},
"headerStyle": func(statName string) template.HTMLAttr {
return template.HTMLAttr(fmt.Sprintf("style=\"background-color: %s;\"", stat2Color(statName)))
},
"barStyle": func(statName string, dividend, divisor time.Duration) template.HTMLAttr {
width := "0"
if divisor != 0 {
width = fmt.Sprintf("%.2f%%", float64(dividend)/float64(divisor)*100)
}
return template.HTMLAttr(fmt.Sprintf("style=\"width: %s; background-color: %s;\"", width, stat2Color(statName)))
},
}).Parse(`
Goroutines: {{.Name}}
Goroutines
Table of contents
Summary
Breakdown
The table below breaks down where each goroutine is spent its time during the
traced period.
All of the columns except total time are non-overlapping.
Goroutine |
Total |
|
{{range $.NonOverlappingStats}}
{{.}} |
{{end}}
{{range .Goroutines}}
{{.ID}} |
{{ .TotalTime.String }} |
{{$Goroutine := .}}
{{range $.NonOverlappingStats}}
{{$Time := index $Goroutine.NonOverlappingStats .}}
{{if $Time}}
{{end}}
{{end}}
|
{{$Goroutine := .}}
{{range $.NonOverlappingStats}}
{{$Time := index $Goroutine.NonOverlappingStats .}}
{{$Time.String}} |
{{end}}
{{end}}
Special ranges
The table below describes how much of the traced period each goroutine spent in
certain special time ranges.
If a goroutine has spent no time in any special time ranges, it is excluded from
the table.
For example, how much time it spent helping the GC. Note that these times do
overlap with the times from the first table.
In general the goroutine may not be executing in these special time ranges.
For example, it may have blocked while trying to help the GC.
This must be taken into account when interpreting the data.
Goroutine |
Total |
{{range $.RangeStats}}
{{.}} |
{{end}}
{{range .Goroutines}}
{{if .HasRangeTime}}
{{.ID}} |
{{ .TotalTime.String }} |
{{$Goroutine := .}}
{{range $.RangeStats}}
{{$Time := index $Goroutine.RangeTime .}}
{{$Time.String}} |
{{end}}
{{end}}
{{end}}
`))