node-process-metrics

Get process, system, memory, CPU, and event loop metrics from a Node.js process. Can be used synchronously, or as an event emitter.

Basic Usage

'use strict';
const NodeProcessMetrics = require('node-process-metrics');

// Use synchronously
const pm = new NodeProcessMetrics();
console.log(pm.metrics());

// Use as an event emitter
const pm = new NodeProcessMetrics({ period: 1000 });

pm.on('metrics', (metrics) => {
  console.log(metrics);
});

API

node-process-metrics exports a single constructor with the following API.

NodeProcessEmitter([options])

• Arguments
  • options (object) - An optional configuration supporting the following options:
    • period (number) - The amount of time that should pass between 'metrics' events being emitted. If not specified, 'metrics' events will not automatically be emitted.
    • loop (boolean) - Indicates whether event loop delays should be measured. If false, event loop delays will be reported as NaN. Defaults to true.
    • loopPeriod (number) - The period used to sample the event loop delay. Defaults to 1000 (one second). Ignored if loop is false.

'metrics' Event

The 'metrics' event contains the following data.

• process (object) - Process level information.
• system (object) - System level information containing the following fields, including the system architecture, hostname, load average, platform, amount of free memory, amount of total memory, and system uptime.
• cpu (array) - Result of Os.cpus().
• loop (number) - The delay associated with each event loop turn, measured in milliseconds.
• handles (number) - The number of handles associated with the event loop.
• requests (number) - The number of requests associated with the event loop.