How to get CPU usage in JavaScript?

Question

Is there a way to get the CPU(s) usage in JavaScript on the browser?

The link that suggest the duplication does not exist any more — Moacir Rosa, Jul 10 '18 at 01:10
There is a way to check it in Node.js and request it in Javascript. — Afia, Nov 18 '19 at 12:35

score 19 · Accepted Answer · edited May 23 '17 at 12:32

19

From what I have gathered, the most you can find out natively in the browser about JS CPU stats, is the amount of CPU cores the client is using. Insert this in your JS file:

console.log(navigator.hardwareConcurrency)

You can then check that in the Chrome Dev Tools console.

However, you can calculate the CPU load using Node.js. Here is a step-by-step on that.

The answer on this page may also be of help in your dilemma: Javascript- Dynamically monitor CPU/memory usage

edited May 23 '17 at 12:32

Community

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answered Sep 15 '16 at 18:23

protoEvangelion

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Is there any way to get only the CPUs that are being used by a node process? os.cpus() gets all the CPUs in a system, doesn't it? – Ronald C Apr 27 '21 at 16:38
It returns me 4? – RixTheTyrunt Jan 09 '23 at 14:30

score 6 · Answer 2 · answered Apr 05 '19 at 10:37

Essentially, no. BUT... and this is a big BUT, if your application is an SPA you could consider deploying it via Electron.

If you did this you could then access the CPU usage: https://electronjs.org/docs/api/structures/cpu-usage

For you it's not a big leap to move from the web to Electron. But for your users it's a big change from accessing something in the browser to downloading an app. However, if this is a very important feature of your app/service then it might be worth it...

Even if your app is not targeting Electron, it's possible to deploy any SPA to Electron and you can monitor the CPU usage there. — M.K. Safi, May 12 '20 at 23:03

score 1 · Answer 3 · edited Aug 30 '22 at 22:05

The answer you may be looking for is measuring the current CPU intensitivity.

if((new Date()).getDay()==6){}else{

work = new Worker("data:text/javascript,setInterval(` dl=Date.now();for(itr=1;itr<1000;itr++){};dl=Date.now()-dl;postMessage(dl);`,1000);");

work.onmessage = (evt)=>{
     console.info(12 - evt.data+(' point'+((new Intl.PluralRules(navigator.language)).select(12-evt.data)=='one'?'':'s')))
       };
   }

Workers would measure the CPU speed of looping.

score 0 · Answer 4 · answered Mar 27 '23 at 12:51

0

On nodeJS there is a library : systeminformation npm systeminformation This library provides system information like CPU, Memory, battery, and more, on several OS: Windows, Linux, Sun, and Mac. It requires Node, I do not think it would work on webapp.

answered Mar 27 '23 at 12:51

Ida Amit

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score 0 · Answer 5 · answered Mar 29 '23 at 21:47

Try using

navigator.hardwareConcurrency

Example:

alert(navigator.hardwareConcurrency);

<html>

<body>
  <h1>The CPU usage will be logged to the console.</h1>
  <script>
    console.log(navigator.hardwareConcurrency);
  </script>
</body>

</html>

score 0 · Answer 6 · answered Jun 19 '23 at 23:56

0

Since the question says:

on the browser

Maybe it's helpful to know that Microsoft Edge(not sure if it's exclusive) has a tab called "Performance Monitor" inside it's dev tools. It shows CPU Usage, JS Heap size, etc.

answered Jun 19 '23 at 23:56

Vasil Verdouw

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While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. - [From Review](/review/late-answers/34570698) – MCGRAW Jun 22 '23 at 22:30
@MCGRAW I thought I was doing this by mentioning the tab's existence inside the dev tools. I'm not sure what else I would need to provide, the link is just a more extensive explanation of what the performance monitor does. The link changing wouldn't change the answer. Could you please clarify what I need to add or change to give a complete answer? – Vasil Verdouw Jun 26 '23 at 23:28

How to get CPU usage in JavaScript?

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