PressureObserver
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 PressureObserver interface is part of the Compute Pressure API and is used to observe the pressure changes of system resources such as the CPU.
Constructor
PressureObserver()-
Creates and returns a new
PressureObserverobject.
Static properties
PressureObserver.knwonSourcesRead only-
Returns an array of
sourcevalues supported by the user agent.
Instance methods
PressureObserver.observe()-
Invokes the pressure observer's callback function when a pressure record for the specified
sourceis observed. PressureObserver.unobserve()-
Stops the pressure observer callback from receiving pressure records from the specified
source. PressureObserver.disconnect()-
Stops the pressure observer callback from receiving pressure records from all sources.
PressureObserver.takeRecords()-
Returns the current list of pressure records stored in the pressure observer, emptying it out.
Examples
Log current pressure
This example creates a PressureObserver and takes action whenever there is a pressure change. The sample interval is set to 1000ms, meaning that there will be updates at most every second.
function callback(records) {
const lastRecord = records[records.length - 1];
console.log(`Current pressure ${lastRecord.state}`);
if (lastRecord.state === "critical") {
// disable video feeds
} else if (lastRecord.state === "serious") {
// disable video filter effects
} else {
// enable all video feeds and filter effects
}
}
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-pressureobserver-object |
Browser compatibility
| desktop | mobile | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
PressureObserver | |||||||||||
PressureObserver() constructor | |||||||||||
disconnect | |||||||||||
knownSources_static | |||||||||||
observe | |||||||||||
takeRecords | |||||||||||
unobserve | |||||||||||