Important: This documentation is about an older version. It's relevant only to the release noted, many of the features and functions have been updated or replaced. Please view the current version.

Configure the client to send profiles

Language SDKs

Node.js

Open source

Node.js

Enhance your Node.js application’s performance with our Node.js Profiler. Seamlessly integrated with Pyroscope, it provides real-time insights into your application’s operation, helping you identify and resolve performance bottlenecks. This integration is key for Node.js developers aiming to boost efficiency, reduce latency, and maintain optimal application performance.

Note
Refer to Available profiling types for a list of profile types supported by each language.

Before you begin

To capture and analyze profiling data, you need either a hosted Pyroscope OSS server or a hosted Pyroscope instance with Grafana Cloud Profiles (requires a free Grafana Cloud account).

The Pyroscope server can be a local server for development or a remote server for production use.

Add Node.js profiling to your application

To start profiling a Node.js application, you need to include the npm module in your app:

npm install @pyroscope/nodejs

# or
yarn add @pyroscope/nodejs

Configure the Node.js client

Add the following code to your application:

const Pyroscope = require('@pyroscope/nodejs');

Pyroscope.init({
  serverAddress: 'http://pyroscope:4040',
  appName: 'myNodeService'
});

Pyroscope.start()

Note
If you’d prefer, you can use Pull mode using Grafana Alloy (recommended) or Grafana Agent (legacy).

Configuration options

Init parameter	ENVIRONMENT VARIABLE	Type	DESCRIPTION
`appName:	`PYROSCOPE_APPLICATION_NAME`	String	Sets the `service_name` label
`serverAddress:`	`PYROSCOPE_SERVER_ADDRESS`	String	URL of the Pyroscope Server
`basicAuthUser:`	n/a	String	Username for basic auth / Grafana Cloud stack user ID (Default `""`)
`basicAuthPassword:`	n/a	String	Password for basic auth / Grafana Cloud API key (Default `""`)
`flushIntervalMs:`	`PYROSCOPE_FLUSH_INTERVAL_MS`	Number	Interval when profiles are sent to the server (Default `60000`)
`heapSamplingIntervalBytes`	`PYROSCOPE_HEAP_SAMPLING_INTERVAL_BYTES`	Number	Average number of bytes between samples. (Default `524288`)
`heapStackDepth:`	`PYROSCOPE_HEAP_STACK_DEPTH`	Number	Maximum stack depth for heap samples (Default `64`)
`wallSamplingDurationMs:`	`PYROSCOPE_WALL_SAMPLING_DURATION_MS`	Number	Duration of a single wall profile (Default `60000`)
`wallSamplingIntervalMicros:`	`PYROSCOPE_WALL_SAMPLING_INTERVAL_MICROS`	Number	Interval of how often wall samples are collected (Default `10000`
`wallCollectCpuTime:`	`PYROSCOPE_WALL_COLLECT_CPU_TIME`	Boolean	Enable CPU time collection for wall profiles (Default `false`)
`tags:`	n/a	LabelSet	Static labels applying to all profiles collected (Default `{}`)
`sourceMapper:`	n/a	SourceMapper	Provide source file mapping information (Default `undefined`)

Add profiling labels to Node.js applications

Static labels

You can add static labels to the profiling data. These labels can be used to filter the data in the UI and apply for all profiles collected. Common static labels include:

hostname
region
team

Pyroscope.init({
  serverAddress: 'http://pyroscope:4040',
  appName: 'myNodeService',
  tags: {
    region: ENV['region']
  },
});

Pyroscope.start()

Dynamic labels for Wall/CPU profiles

In Wall/CPU profiles, labels can also be attached dynamically and help to separate different code paths:

Pyroscope.wrapWithLabels({ vehicle: 'bike' }, () =>
  slowCode()
);

Send data to Pyroscope OSS or Grafana Cloud

Pyroscope.init({
  serverAddress: 'http://pyroscope:4040',
  appName: 'myNodeService',
  tags: {
    region: ENV['region']
  },
  basicAuthUser: ENV['PYROSCOPE_BASIC_AUTH_USER'],
  basicAuthPassword: ENV['PYROSCOPE_BASIC_AUTH_PASSWORD'],
  // Optional Pyroscope tenant ID (only needed if using multi-tenancy). Not needed for Grafana Cloud.
  // tenantID: ENV['PYROSCOPE_TENANT_ID'],
});

Pyroscope.start()

To configure the Node.js SDK to send data to Pyroscope, replace the serverAddress placeholder with the appropriate server URL. This could be the Grafana Cloud Pyroscope URL or your own custom Pyroscope server URL.

If you need to send data to Grafana Cloud, you’ll have to configure HTTP Basic authentication. Replace basicAuthUser with your Grafana Cloud stack user ID and basicAuthPassword with your Grafana Cloud API key.

If your Pyroscope server has multi-tenancy enabled, you’ll need to configure a tenant ID. Replace tenantID with your Pyroscope tenant ID.