The Performance
interface provides access to performance-related information for the current page. It's part of the High Resolution Time API, but is enhanced by the Performance Timeline API, the Navigation Timing API, the User Timing API, and the Resource Timing API.
Documentation Performance by Mozilla Contributors, licensed under CC-BY-SA 2.5.
See also:
Variables
read onlynavigation:PerformanceNavigation
A PerformanceNavigation
object that provides useful context about the operations included in the times listed in timing
, including whether the page was a load or a refresh, how many redirections occurred, and so forth.
onresourcetimingbufferfull:Function
An EventTarget
which is a callback that will be called when the resourcetimingbufferfull
event is fired.
read onlytimeOrigin:Float
Returns the high resolution timestamp of the start time of the performance measurement.
read onlytiming:PerformanceTiming
A PerformanceTiming
object containing latency-related performance information
Methods
clearMarks(?markName:String):Void
Removes the given mark from the browser's performance entry buffer.
clearMeasures(?measureName:String):Void
Removes the given measure from the browser's performance entry buffer.
clearResourceTimings():Void
Removes all PerformanceEntry
with a PerformanceEntry.entryType
of "resource
" from the browser's performance data buffer.
getEntries():Array<PerformanceEntry>
Returns a list of PerformanceEntry
objects based on the given filter.
getEntriesByName(name:String, ?entryType:String):Array<PerformanceEntry>
Returns a list of PerformanceEntry
objects based on the given name and entry type.
getEntriesByType(entryType:String):Array<PerformanceEntry>
Returns a list of PerformanceEntry
objects of the given entry type.
mark(markName:String):Void
Creates a DOMHighResTimeStamp
in the browser's performance entry buffer with the given name.
Throws:
null | DOMError |
---|
measure(measureName:String, ?startMark:String, ?endMark:String):Void
Creates a named DOMHighResTimeStamp
in the browser's performance entry buffer between two specified marks (known as the start mark and end mark, respectively).
Throws:
null | DOMError |
---|
now():Float
Returns a DOMHighResTimeStamp
representing the number of milliseconds elapsed since a reference instant.
setResourceTimingBufferSize(maxSize:Int):Void
Sets the browser's resource timing buffer size to the specified number of "resource
" PerformanceEntry.entryType
PerformanceEntry
objects.