如何正确获取有关 CPU 使用率的信息？

Question

I want to get a few metrics from my NodeJS app like cpuUsage for user, system and as total usage. Below is my simple code:

private lastCpuUsage = process.cpuUsage();

getCpuUsage() {
    const cpuUsage = process.cpuUsage();

    const userUsageMicros = cpuUsage.user - this.lastCpuUsage.user;
    const systemUsageMicros = cpuUsage.system - this.lastCpuUsage.system;

    this.lastCpuUsage = cpuUsage;

    console.log({
      cpuUserUsage: userUsageMicros / 1e6, //1000000
      cpuSystemUsage: systemUsageMicros / 1e6,
      cpuTotalUsage: (userUsageMicros + systemUsageMicros) / 1e6
    })
}

and here is a sample output:

{
    "cpuUserUsage": 0.016,
    "cpuSystemUsage": 0.031,
    "cpuTotalUsage": 0.047
}

And now I've got two questions:

1. How to get cpuUsage in percentage unit?
2. This output is for the entire machine on which my application stands or only for a specific application from which I download this data? And if is only for my app, how can I get data from the entire system?

Thanks for any help!

Answer 1

If all the CPUs are in the same spec and processes are using only one CPU, then try with os module. Node OS

const os = require('os');

const [cpu] = os.cpus();

const total = Object.values(cpu.times).reduce(
    (acc, val) => acc + val, 0
);

const { user, system } = process.cpuUsage();
const percentage = 100 * 1000 * (user + system) / total ;

console.log(percentage);