stackimpact

README

StackImpact Go Agent

Overview

StackImpact is a performance profiling and monitoring service for production Go applications. It gives you continuous visibility with line-of-code precision into application performance, such as CPU, memory and IO hot spots as well execution bottlenecks, allowing to optimize applications and troubleshoot issues before they impact customers. Learn more at stackimpact.com.

Main features:

• Automatic hot spot profiling for CPU, memory allocations, network, system calls and lock contention.
• Automatic bottleneck tracing for HTTP handlers and HTTP clients.
• Health monitoring including CPU, memory, garbage collection and other runtime metrics.
• Alerts on hot spot anomalies.
• Multiple account users for team collaboration.

Learn more on features page (with screenshots).

StackImpact agent (this package) reports performance information to the Dashboard running as SaaS or On-Premise.

Requirements

Linux or OS X. Go version 1.5+.

Getting started

Create StackImpact account

Sign up for a free account at stackimpact.com.

Installing the agent

Install the Go agent by running

go get github.com/stackimpact/stackimpact-go

And import the package github.com/stackimpact/stackimpact-go in your application.

Configuring the agent

Start the agent by specifying agent key and application name. The agent key can be found in your account's Configuration section.

agent := stackimpact.NewAgent();
agent.Configure("agent key here", "MyGoApp")

Other initialization options are (set before calling Configure):

• agent.DashboardAddress (Optional) Used by on-premises deployments only.
• agent.HostName (Optional) By default host name will be the OS hostname.
• agent.Debug (Optional) Enables debug logging.

Example:

package main

import (
  	"fmt"
  	"net/http"

  	"github.com/stackimpact/stackimpact-go"
)

func handler(w http.ResponseWriter, r *http.Request) {
  	fmt.Fprintf(w, "Hello world!")
}

func main() {
  	agent := stackimpact.NewAgent()
  	agent.Configure("agent key here", "Basic Go Server")

  	http.HandleFunc("/", handler)
    http.ListenAndServe(":8080", nil)
}

Measuring code segments (OPTIONAL)

To measure performance and detect bottlenecks in arbitrary parts of application, the segment API can be used.

segment := agent.MeasureSegment("Segment1")
defer segment.Stop()

subsegment := agent.MeasureSubsegment("Segment1", "Subsegment1")
defer subsegment.Stop()

Analyzing performance data in the Dashboard

Once your application is restarted, start observing regular and anomaly-triggered CPU, memory, IO, and other hot spot profiles, execution bottlenecks as well as process metrics in the Dashboard.

Troubleshooting

To enable debug logging, add agent.Debug = true to startup options. If debug log doesn't give you any hints on how to fix a problem, please report it to our support team in your account's Support section.

Overhead

Reporting CPU, network and system profiles requires regular and anomaly-triggered profiling and tracing activation for short periods of time. Unlike memory profiling and process-level metric reporting, they produce some overhead when active. The agent makes sure the overhead stays within 2% and has no effect on application in any way.

Documentation

Index

• type Agent
  • func NewAgent() *Agent
  • func (a *Agent) Configure(agentKey string, appName string)
  • func (a *Agent) MeasureSegment(segmentName string) *Segment
  • func (a *Agent) MeasureSubsegment(segmentName string, subsegmentName string) *Segment
• type Segment
  • func (s *Segment) Stop()

Types

type Agent

type Agent struct {
	DashboardAddress string
	HostName         string
	Debug            bool
	// contains filtered or unexported fields
}

func NewAgent

func NewAgent() *Agent

func (*Agent) Configure

func (a *Agent) Configure(agentKey string, appName string)

func (*Agent) MeasureSegment

func (a *Agent) MeasureSegment(segmentName string) *Segment

func (*Agent) MeasureSubsegment

func (a *Agent) MeasureSubsegment(segmentName string, subsegmentName string) *Segment

type Segment

type Segment struct {
	Path []string

	Duration int64
	// contains filtered or unexported fields
}

func (*Segment) Stop

func (s *Segment) Stop()