Monitor Go Profiler

Overview

SnappyFlow profiler collects

• Profiles (supported: cpu, heap, block, mutex, goroutine, threadcreate)
• Runtime metrics

and sends them to SnappyFlow for further visualization and analysis.

cpu and heap profiles are enabled by default and other profiles can be enabled as required.

• godoc: https://pkg.go.dev/github.com/snappyflow/sf-go-profiler/profiler

• sample code: https://github.com/snappyflow/sf-go-profiler/tree/main/example/main.go

Getting started

• Pre-requisites

  • Install and configure snappyflow agent on vm or as a sidecar in the container, as it is required to send data to snappyflow-apm

  • Run the below command to download or update sf-go-profiler package in your current project.

    go get -u -v github.com/snappyflow/sf-go-profiler/profiler

• Example

import "github.com/snappyflow/sf-go-profiler/profiler"

main(){
    profile := profiler.NewProfilerConfig("server")
    profile.Start()
    defer profile.Stop()
    // rest of the application code
}

• profiling can conditionally enabled when required using golang flags

import (
    "github.com/snappyflow/sf-go-profiler/profiler"
    "flag"
)

main(){
    enableprofile := flag.Bool("profile",false,"enable profiler")
    if *enableprofile {
        profile := profiler.NewProfilerConfig("server")
        // below line disables collection of go runtime metrics
        // profile.DisableRuntimeMetrics()
        // below line disables profiling
        // profile.DisableProfiles()
        profile.Start()
        defer profile.Stop()
    }
    // rest of the application code
}

• runtime metrics can be disable by calling DisableRuntimeMetrics() similarly profiling can be disabled by calling DisableProfiles() on profile config object.

    profile := profiler.NewProfilerConfig("server")
    // below line disables collection of go runtime metrics
    profile.DisableRuntimeMetrics()
    // below line disables profiling
    profile.DisableProfiles()
    profile.Start()
    defer profile.Stop()

• enable other supported profiles as required

    // enable block profile and set given block profile rate
    profile.EnableBlockProfile(100)
    // enable mutex profile and set given mutex profile fraction
    profile.EnableMutexProfile(1000)
    // enable goroutine profile
    profile.EnableGoRoutineProfile()
    // enable threadcreate profile
    profile.EnableThreadCreateProfile()

• since only heap and cpu profiles are enabled by default, all supported profiles can be enabled by call to function EnableAllProfiles(), this sets block profile rate to DefaultBlockProfileRate and mutex profile fraction to DefaultMutexProfileFraction

    // enable all supported profiles
    profile.EnableAllProfiles()

Sample runtime metrics collected

• reference: https://pkg.go.dev/runtime#MemStats

{
  "alloc_mb": 8.4275,
  "frees": 28575,
  "gc_cpu_fraction": 0.0001,
  "go_version": "go1.16.4",
  "interval": 60,
  "last_gc": 1631099627396,
  "live_objects": 27146,
  "mallocs": 27361,
  "max_pause_gc_ms": 0.1033,
  "min_pause_gc_ms": 0.0366,
  "num_cpu": 2,
  "num_gc": 2,
  "num_goroutines": 23,
  "pid": 23201,
  "sys_mb": 71.5791,
  "time": 1631099686505,
  "total_alloc_mb": 8.8994,
  "total_pause_gc_ms": 0.14,
}