Performance.measure()

The measure() method creates a named PerformanceMeasure object representing a time measurement between two marks in the browser’s performance timeline.

When measuring between two marks, there is a start mark and end mark, respectively. The named timestamp is referred to as a measure.

Inputs: measureName A string representing the name of the measure.

Inputs: start Timestamp (DOMHighResTimeStamp) to be used as the start time, or string that names a PerformanceMark to use for the start time.

Inputs: If this is a string naming a PerformanceMark, then it is defined in the same way as startMark.

Inputs: duration Duration (in milliseconds) between the start and end mark times. If omitted, this defaults to performance.now(); the time that has elapsed since the context was created. If provided, you must also specify either start or end but not both.