ReadonlydetailThe read-only detail property returns arbitrary metadata that was included in the mark upon construction (either when using Performance.mark or the PerformanceMark.PerformanceMark constructor).
ReadonlydurationThe read-only duration property returns a DOMHighResTimeStamp that is the duration of the PerformanceEntry.
ReadonlyentryThe read-only entryType property returns a string representing the type of performance metric that this entry represents.
ReadonlynameThe read-only name property of the PerformanceEntry interface is a string representing the name for a performance entry.
ReadonlystartThe read-only startTime property returns the first DOMHighResTimeStamp recorded for this PerformanceEntry.
PerformanceMarkis an interface for PerformanceEntry objects with an PerformanceEntry.entryType of'mark'.MDN Reference