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