event-loop-lag

Measures Node.js event loop lag.

var interval = 1000; // how often to refresh our measurement
var lag = require('event-loop-lag')(interval);
 
console.log('event loop lag is %d', lag());

event-loop-lag(number)

event-loop-lag accepts a number of milliseconds representing how often to refresh the event loop lag measurement and returns a function you can call to receive the latest lag measurement in milliseconds.

var lag = require('event-loop-lag')(1000);
var koa = require('koa');
var app = koa();
 
app.use(function*(next){
  if ('/lag' == this.url)
    this.body = lag() + ' milliseconds';
  else
    yield next;
})

Installation

npm install event-loop-lag --save

Development

running tests

• make test runs tests
• make test-cov runs tests + test coverage
• make open-cov opens test coverage results in your browser

verbose logging

event-loop-lag supports the debug module for help during development. Enable verbose logging by setting your DEBUG env variable like so:

DEBUG=event-loop-lag* npm test

Sponsored by

Pebble Technology!

License

MIT