W3cubDocs

/DOM

WorkerGlobalScope.performance

The performance read-only property of the WorkerGlobalScope interface returns a Performance object to be used on the worker.

Not all Performance properties and methods are available to Web workers.

This property is Read only .

Syntax

var perfObj = self.performance;

Return Value

A Performance object.

Example

If you called

console.log(performance);

inside a worker (which would basically be the equivalent of self.console.log(self.performance);, as these are being called on the worker scope, which can be referenced with WorkerGlobalScope.self), you will get a WorkerPerformance object written to the console — something like the following:

WorkerPerformance {now: function}
  __proto__: WorkerPerformance
    constructor: function WorkerPerformance() { [native code] }
    now: function now() { [native code] }
    __proto__: Object

You could use this performance object to return performance data, as you might do with a normal Performance object.

Note: Firefox has a bug with using console.log inside shared/service workers (see bug 1058644), which may return strange results, but this should be fixed soon.

Specifications

Specification Status Comment
High Resolution Time Level 2
The definition of 'performance' in that specification.
Candidate Recommendation Defines WorkerGlobalScope.performance.

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
Basic support Yes ? 34 ? ? ?
Mobile
Android webview Chrome for Android Edge Mobile Firefox for Android Opera for Android iOS Safari Samsung Internet
Basic support ? Yes ? 34 ? ? Yes

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/WorkerGlobalScope/performance