CPUtilization

Installation

npm install cputilization

Invocation

This modules sample the cpu utilization. The interface works via callback or event emitter.

callback interface

use the callback interface if the cpu usage should be sampled only once:

var cpuu = require('cputilization');

cpuu(function(error, sample) {
    //returns after 1000ms with the cpu usage of that time interval
    console.log( sample.percentageBusy() );
});

supply an options hash to specify the time interval:

var cpuu = require('cputilization');

cpuu({timeout: 2000}, function(error, sample) {
    //returns after 2000ms
    console.log( sample.percentageBusy() );
});

event emitter interface

if no callback is supplied the cpu utilization will be sampled continously.

a event emitter is returned than, emits a sample event every 1000ms

var cpuu = require('cputilization');

var sampler = cpuu();

sampler.on('sample', function(sample) {
    console.log( sample.percentageBusy() );
});

an additional options hash can be provided:

• interval: the ticking interval, default: 1000ms
• autoStart: automatically start the ticker, default: true

var cpuu = require('cputilization');

var sampler = cpuu({interval:100, autoStart: false});

sampler.on('sample', function(sample) {
    console.log( sample.percentageBusy() );
});

start sampling

if the sampler does not start automatically it can be started via the start command:

var cpuu = require('cputilization');

var sampler = cpuu({autoStart: false, interval:100});

sampler.on('sample', function(sample) {
    //gets executed every 100ms
    console.log( sample.percentageBusy() );
});

sampler.start();

stop sampling

the returned event emitter features a stop method, use that one to stop sampling:

var cpuu = require('cputilization');

var sampler = cpuu({interval:100});

sampler.on('sample', function(sample) {
    //gets executed every 100ms
    console.log(sample.percentageBusy());
});

sampler.stop();

CpuSample

An CpuSample object is emitted (EventEmitter interface) or returned via tha callback interface.
The following methods are available:

percentageBusy()

Returns the average CpuUtilization over the specified sampling interval.

percentageIdle()

Returns the average Cpu Idle percentage of the specified sampling interval.