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. |
Recommendation | Defines WorkerGlobalScope.performance. |
Browser compatibility
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
performance | Chrome Full support Yes | Edge Full support ≤79 | Firefox Full support 34 | IE ? | Opera ? | Safari ? | WebView Android Full support Yes | Chrome Android Full support Yes | Firefox Android Full support 34 | Opera Android ? | Safari iOS ? | Samsung Internet Android Full support Yes |
Legend
- Full support
- Full support
- Compatibility unknown
- Compatibility unknown
