PressureRecord: state property

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

Note: This feature is available in Web Workers, except for Service Workers.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The read-only state property is a string indicating the pressure state recorded.

Value

A string indicating the pressure state recorded. The Compute Pressure API uses human-readable pressure states with the following semantics (see also the specification):

  • ⚪ "nominal": The conditions of the target device are at an acceptable level with no noticeable adverse effects on the user.
  • 🟢 "fair": Target device pressure, temperature and/or energy usage are slightly elevated, potentially resulting in reduced battery-life, as well as fans (or systems with fans) becoming active and audible. Apart from that the target device is running flawlessly and can take on additional work.
  • 🟡 "serious": Target device pressure, temperature and/or energy usage is consistently highly elevated. The system may be throttling as a countermeasure to reduce thermals.
  • 🔴 "critical": The temperature of the target device or system is significantly elevated and it requires cooling down to avoid any potential issues.

Examples

Using the state property

In the following example we log the value of the state property in the pressure observer callback.

js
function callback(records) {
  const lastRecord = records[records.length - 1];
  console.log(`Current pressure is ${lastRecord.state}`);
}

try {
  const observer = new PressureObserver(callback);
  await observer.observe("cpu", {
    sampleInterval: 1000, // 1000ms
  });
} catch (error) {
  // report error setting up the observer
}

Specifications

Specification
Compute Pressure Level 1
# the-state-attribute

Browser compatibility

desktop mobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
state
Experimental
Chrome – Full support
Chrome 125 (Release date: 2024-05-14)
footnote Full support
Edge – Full support
Edge 125 (Release date: 2024-05-17)
footnote Full support
Firefox – No support
Firefox
footnote No support
Opera – Full support
Opera 111 (Release date: 2024-06-12)
footnote Full support
Safari – No support
Safari
footnote No support
Chrome Android – No support
Chrome Android
footnote No support
Firefox for Android – No support
Firefox for Android
footnote No support
Opera Android – No support
Opera Android
footnote No support
Safari on iOS – No support
Safari on iOS
footnote No support
Samsung Internet – No support
Samsung Internet
footnote No support
WebView Android – No support
WebView Android
footnote No support
WebView on iOS – No support
WebView on iOS
footnote No support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support
No support
No support
Experimental. Expect behavior to change in the future.