PerformanceObserver

The PerformanceObserver interface is used to observe performance measurement events and be notified of new performance entries as they are recorded in the browser's performance timeline.

Note: This feature is available in Web Workers

Constructor

PerformanceObserver(): Creates and returns a new PerformanceObserver object.

Properties

PerformanceObserver.supportedEntryTypesRead only: Returns an array of the entryType values supported by the user agent.

Methods

PerformanceObserver.observe(): Specifies the set of entry types to observe. The performance observer's callback function will be invoked when a performance entry is recorded for one of the specified entryTypes
PerformanceObserver.disconnect(): Stops the performance observer callback from receiving performance entries.
PerformanceObserver.takeRecords(): Returns the current list of performance entries stored in the performance observer, emptying it out.

Example

function observer_callback(list, observer) {
   // Process the "measure" event
}
let observer = new PerformanceObserver(observer_callback);
observer.observe({entryTypes: ["measure"]});

Specifications

Specification
Performance Timeline Level 2 (Performance Timeline 2) # dom-performanceobserver

Browser compatibility

BCD tables only load in the browser