README

profile

Simple profiling support package for Go

installation

go get github.com/pkg/profile

usage

Enabling profiling in your application is as simple as one line at the top of your main function

import "github.com/pkg/profile"

func main() {
    defer profile.Start().Stop()
    ...
}

options

What to profile is controlled by config value passed to profile.Start. By default CPU profiling is enabled.

import "github.com/pkg/profile"

func main() {
    // p.Stop() must be called before the program exits to
    // ensure profiling information is written to disk.
    p := profile.Start(profile.MemProfile, profile.ProfilePath("."), profile.NoShutdownHook)
    ...
    // You can enable different kinds of memory profiling, either Heap or Allocs where Heap
    // profiling is the default with profile.MemProfile.
    p := profile.Start(profile.MemProfileAllocs, profile.ProfilePath("."), profile.NoShutdownHook)
}

Several convenience package level values are provided for cpu, memory, and block (contention) profiling.

For more complex options, consult the documentation.

contributing

We welcome pull requests, bug fixes and issue reports.

Before proposing a change, please discuss it first by raising an issue.

Documentation

Overview

Package profile provides a simple way to manage runtime/pprof profiling of your Go application.

Index

• Constants
• func BlockProfile(p *Profile)
• func CPUProfile(p *Profile)
• func GoroutineProfile(p *Profile)
• func MemProfile(p *Profile)
• func MemProfileAllocs() func(*Profile)
• func MemProfileHeap() func(*Profile)
• func MemProfileRate(rate int) func(*Profile)
• func MutexProfile(p *Profile)
• func NoShutdownHook(p *Profile)
• func ProfilePath(path string) func(*Profile)
• func Quiet(p *Profile)
• func Start(options ...func(*Profile)) interface{ ... }
• func ThreadcreationProfile(p *Profile)
• func TraceProfile(p *Profile)
• type Profile
  • func (p *Profile) Stop()

Examples

• CPUProfile
• MemProfile
• MemProfileRate
• NoShutdownHook
• ProfilePath
• Start
• Start (WithFlags)
• TraceProfile

Constants

const DefaultMemProfileRate = 4096

DefaultMemProfileRate is the default memory profiling rate. See also http://golang.org/pkg/runtime/#pkg-variables

Variables

This section is empty.

Functions

func BlockProfile

func BlockProfile(p *Profile)

BlockProfile enables block (contention) profiling. It disables any previous profiling settings.

func CPUProfile

func CPUProfile(p *Profile)

CPUProfile enables cpu profiling. It disables any previous profiling settings.

Example

package main import ( "github.com/pkg/profile" ) func main() { // CPU profiling is the default profiling mode, but you can specify it // explicitly for completeness. defer profile.Start(profile.CPUProfile).Stop() }

func GoroutineProfile

func GoroutineProfile(p *Profile)

GoroutineProfile enables goroutine profiling. It disables any previous profiling settings.

func MemProfile

func MemProfile(p *Profile)

MemProfile enables memory profiling. It disables any previous profiling settings.

Example

package main import ( "github.com/pkg/profile" ) func main() { // use memory profiling, rather than the default cpu profiling. defer profile.Start(profile.MemProfile).Stop() }

func MemProfileAllocs

func MemProfileAllocs() func(*Profile)

MemProfileAllocs changes which type of memory to profile allocations.

func MemProfileHeap

func MemProfileHeap() func(*Profile)

MemProfileHeap changes which type of memory profiling to profile the heap.

func MemProfileRate

func MemProfileRate(rate int) func(*Profile)

MemProfileRate enables memory profiling at the preferred rate. It disables any previous profiling settings.

Example

package main import ( "github.com/pkg/profile" ) func main() { // use memory profiling with custom rate. defer profile.Start(profile.MemProfileRate(2048)).Stop() }

func MutexProfile

func MutexProfile(p *Profile)

MutexProfile enables mutex profiling. It disables any previous profiling settings.

func NoShutdownHook

func NoShutdownHook(p *Profile)

NoShutdownHook controls whether the profiling package should hook SIGINT to write profiles cleanly. Programs with more sophisticated signal handling should set this to true and ensure the Stop() function returned from Start() is called during shutdown.

Example

package main import ( "github.com/pkg/profile" ) func main() { // disable the automatic shutdown hook. defer profile.Start(profile.NoShutdownHook).Stop() }

func ProfilePath

func ProfilePath(path string) func(*Profile)

ProfilePath controls the base path where various profiling files are written. If blank, the base path will be generated by ioutil.TempDir.

Example

package main import ( "os" "github.com/pkg/profile" ) func main() { // set the location that the profile will be written to defer profile.Start(profile.ProfilePath(os.Getenv("HOME"))).Stop() }

func Quiet

func Quiet(p *Profile)

Quiet suppresses informational messages during profiling.

func Start

func Start(options ...func(*Profile)) interface {
	Stop()
}

Start starts a new profiling session. The caller should call the Stop method on the value returned to cleanly stop profiling.

Example

package main import ( "github.com/pkg/profile" ) func main() { // start a simple CPU profile and register // a defer to Stop (flush) the profiling data. defer profile.Start().Stop() }

Example (WithFlags)

package main import ( "flag" "github.com/pkg/profile" ) func main() { // use the flags package to selectively enable profiling. mode := flag.String("profile.mode", "", "enable profiling mode, one of [cpu, mem, mutex, block]") flag.Parse() switch *mode { case "cpu": defer profile.Start(profile.CPUProfile).Stop() case "mem": defer profile.Start(profile.MemProfile).Stop() case "mutex": defer profile.Start(profile.MutexProfile).Stop() case "block": defer profile.Start(profile.BlockProfile).Stop() default: // do nothing } }

func ThreadcreationProfile

func ThreadcreationProfile(p *Profile)

ThreadcreationProfile enables thread creation profiling.. It disables any previous profiling settings.

func TraceProfile

func TraceProfile(p *Profile)

Trace profile enables execution tracing. It disables any previous profiling settings.

Example

package main import ( "github.com/pkg/profile" ) func main() { // use execution tracing, rather than the default cpu profiling. defer profile.Start(profile.TraceProfile).Stop() }

Types

type Profile

type Profile struct {
	// contains filtered or unexported fields
}

Profile represents an active profiling session.

func (*Profile) Stop

func (p *Profile) Stop()

Stop stops the profile and flushes any unwritten data.