Variable PerformanceUtilsConst

Type declaration

• clearMarksAndMeasures:function

  • clearMarksAndMeasures(): void

  • Clears all performance marks and measures

    Returns void

• createPerformanceObserver:function

  • createPerformanceObserver(callback, entryTypes): PerformanceObserver

  • Creates a performance observer

    Parameters

    • callback: ((entries) => void)

      Function to call when performance entries are observed

      • • (entries): void

        • Parameters

          • entries: PerformanceObserverEntryList

          Returns void

    • entryTypes: string[]

      Types of entries to observe

    Returns PerformanceObserver

    Performance observer

• getCumulativeLayoutShift:function

  • getCumulativeLayoutShift(): Promise<number>

  • Gets the cumulative layout shift

    Returns Promise<number>

    Promise resolving to CLS score

• getDomContentLoadedTime:function

  • getDomContentLoadedTime(): Promise<number>

  • Gets the DOM content loaded time

    Returns Promise<number>

    Promise resolving to DOM content loaded time in milliseconds

• getFirstContentfulPaint:function

  • getFirstContentfulPaint(): Promise<number>

  • Gets the first contentful paint time

    Returns Promise<number>

    Promise resolving to FCP time in milliseconds

• getFirstInputDelay:function

  • getFirstInputDelay(): Promise<number>

  • Gets the first input delay

    Returns Promise<number>

    Promise resolving to FID time in milliseconds

• getLargestContentfulPaint:function

  • getLargestContentfulPaint(): Promise<number>

  • Gets the largest contentful paint time

    Returns Promise<number>

    Promise resolving to LCP time in milliseconds

• getPageLoadTime:function

  • getPageLoadTime(): Promise<number>

  • Gets the page load time

    Returns Promise<number>

    Promise resolving to page load time in milliseconds

• getTimeToFirstByte:function

  • getTimeToFirstByte(): Promise<number>

  • Gets the time to first byte (TTFB)

    Returns Promise<number>

    Promise resolving to TTFB in milliseconds

• mark:function

  • mark(name): void

  • Creates a performance mark

    Parameters

    • name: string

      Name of the mark

    Returns void

• measureExecutionTime:function

  • measureExecutionTime<T>(fn, iterations?): {
        result: T;
        time: number;
        averageTime: number;
    }

  • Measures the execution time of a function

    Type Parameters

    • T

    Parameters

    • fn: (() => T)

      Function to measure

      • • (): T

        • Returns T

    • iterations: number = 1

      Number of iterations to run

    Returns {
        result: T;
        time: number;
        averageTime: number;
    }

    Object containing execution time statistics

    • result: T

    • time: number

    • averageTime: number

• measure:function

  • measure(startMark, endMark): null | PerformanceEntry

  • Measures the time between two marks

    Parameters

    • startMark: string

      Name of the start mark
    • endMark: string

      Name of the end mark

    Returns null | PerformanceEntry

    Object containing measurement details

• throttle:function

  • throttle<T>(fn, limit): ((...args) => void)

  • Throttles a function

    Type Parameters

    • T extends ((...args) => any)

    Parameters

    • fn: T

      Function to throttle
    • limit: number

      Time limit in milliseconds

    Returns ((...args) => void)

    Throttled function

    • • (...args): void

      • Parameters

        • Rest ...args: Parameters<T>

        Returns void