Go pprof in Practice

Wed, 22 Jun 2022 15:29:02 +0800

package main

import (
 // omitted
 _ "net/http/pprof" // auto-register handlers to the HTTP server for profiling via HTTP
 // omitted
)

func main() {
 // omitted

 runtime.GOMAXPROCS(1) // limit CPU usage to avoid overload
 runtime.SetMutexProfileFraction(1) // enable lock contention profiling
 runtime.SetBlockProfileRate(1) // enable blocking operation profiling

 go func() {
 // start an HTTP server; pprof handlers have already been registered
 // /debug/pprof/
 if err := http.ListenAndServe(":6060", nil); err != nil {
 log.Fatal(err)
 }
 os.Exit(0)
 }()

 // omitted
}

http://localhost:6060/debug/pprof/

Type	Description	Notes
allocs	Samples of memory allocations	Can open in a browser, but readability is low
blocks	Samples of blocking operations	Can open in a browser, but readability is low
cmdline	Show program startup command/args	Can open in a browser; shows ./go-pprof-practice
goroutine	Stacks of all current goroutines	Can open in a browser, but readability is low
heap	Samples of heap memory usage	Can open in a browser, but readability is low
mutex	Samples of lock contention	Can open in a browser, but readability is low
profile	Samples of CPU usage	Opening in a browser downloads a file
threadcreate	Samples of system thread creation	Can open in a browser, but readability is low
trace	Program execution traces	Opening in a browser downloads a file; not covered here, see Go trace

Investigate high CPU usage

Pprof on Ricky

Go pprof in Practice