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% CPU in Node.JS
const os = require("os");
//Create function to get CPU information
function cpuAverage() {
//Initialise sum of idle and time of cores and fetch CPU info
var totalIdle = 0, totalTick = 0;
var cpus = os.cpus();
//Loop through CPU cores
for (var i = 0, len = cpus.length; i < len; i++) {
//Select CPU core
var cpu = cpus[i];
//Total up the time in the cores tick
for (type in cpu.times) {
totalTick += cpu.times[type];
}
//Total up the idle time of the core
totalIdle += cpu.times.idle;
}
//Return the average Idle and Tick times
return {idle: totalIdle / cpus.length, total: totalTick / cpus.length};
}
// function to calculate average of array
const arrAvg = function (arr) {
if (arr && arr.length >= 1) {
const sumArr = arr.reduce((a, b) => a + b, 0)
return sumArr / arr.length;
}
};
// load average for the past 1000 milliseconds calculated every 100
function getCPULoadAVG(avgTime = 1000, delay = 100) {
return new Promise((resolve, reject) => {
const n = ~~(avgTime / delay);
if (n <= 1) {
reject('Error: interval to small');
}
let i = 0;
let samples = [];
const avg1 = cpuAverage();
let interval = setInterval(() => {
console.debug('CPU Interval: ', i);
if (i >= n) {
clearInterval(interval);
resolve(~~((arrAvg(samples) * 100)));
}
const avg2 = cpuAverage();
const totalDiff = avg2.total - avg1.total;
const idleDiff = avg2.idle - avg1.idle;
samples[i] = (1 - idleDiff / totalDiff);
i++;
}, delay);
});
}
getCPULoadAVG(1000, 100).then((avg) => {
console.log(avg);
});
@Wqrld
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Wqrld commented May 28, 2020

This is to be honest the only right one i could find that actually gives a correct average

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@felipebutcher
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felipebutcher commented Jan 30, 2021

Hey there! Thank you. This was the only one that I found that showed the same values as in htop. I created an NPM package with your code: https://github.com/felipebutcher/node-os-info

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@GaetanoPiazzolla
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Author

GaetanoPiazzolla commented Jan 30, 2021

Thank you Felipe, you are welcome.
Also you have been very kind linking this gist to your repository. :)

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@Guitarman051120
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Guitarman051120 commented May 8, 2021

Sadly, in my case it just reports some random numbers. Still thank you

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@felipebutcher
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felipebutcher commented Aug 21, 2021

Sadly, in my case it just reports some random numbers. Still thank you

@Guitarman051120 What OS are you using?

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