Usage in Deno
import { type Performance } from "node:perf_hooks";
nodeTiming: PerformanceNodeTiming
An instance of the PerformanceNodeTiming class that provides performance metrics for specific Node.js operational milestones.
timeOrigin: number
The timeOrigin specifies the high resolution millisecond timestamp from which all performance metric durations are measured.
eventLoopUtilization is similar to CPU utilization except that it is calculated using high precision wall-clock time. It represents the percentage of time the event loop has spent outside the event loop's event provider (e.g. epoll_wait). No other CPU idle time is taken into consideration.
clearMarks(name?: string): void
If name is not provided, removes all PerformanceMark objects from the Performance Timeline. If name is provided, removes only the named mark.
clearMeasures(name?: string): void
If name is not provided, removes all PerformanceMeasure objects from the Performance Timeline. If name is provided, removes only the named measure.
Returns a list of PerformanceEntry
objects in chronological order with respect to performanceEntry.startTime
.
If you are only interested in performance entries of certain types or that have certain names, see
performance.getEntriesByType()
and performance.getEntriesByName()
.
getEntriesByName(name: string,type?: EntryType,): PerformanceEntry[]
Returns a list of PerformanceEntry
objects in chronological order with respect to performanceEntry.startTime
whose performanceEntry.name
is equal to name
, and optionally, whose performanceEntry.entryType
is equal to type
.
getEntriesByType(type: EntryType): PerformanceEntry[]
Returns a list of PerformanceEntry
objects in chronological order with respect to performanceEntry.startTime
whose performanceEntry.entryType
is equal to type
.
mark(name?: string,options?: MarkOptions,): PerformanceMark
Creates a new PerformanceMark entry in the Performance Timeline. A PerformanceMark is a subclass of PerformanceEntry whose performanceEntry.entryType is always 'mark', and whose performanceEntry.duration is always 0. Performance marks are used to mark specific significant moments in the Performance Timeline.
measure(name: string,startMark?: string,endMark?: string,): PerformanceMeasure
Creates a new PerformanceMeasure entry in the Performance Timeline. A PerformanceMeasure is a subclass of PerformanceEntry whose performanceEntry.entryType is always 'measure', and whose performanceEntry.duration measures the number of milliseconds elapsed since startMark and endMark.
The startMark argument may identify any existing PerformanceMark in the the Performance Timeline, or may identify any of the timestamp properties provided by the PerformanceNodeTiming class. If the named startMark does not exist, then startMark is set to timeOrigin by default.
The endMark argument must identify any existing PerformanceMark in the the Performance Timeline or any of the timestamp properties provided by the PerformanceNodeTiming class. If the named endMark does not exist, an error will be thrown.
measure(name: string,options: MeasureOptions,): PerformanceMeasure
now(): number
timerify<T extends (...params: any[]) => any>(fn: T,options?: TimerifyOptions,): T
Wraps a function within a new function that measures the running time of the wrapped function. A PerformanceObserver must be subscribed to the 'function' event type in order for the timing details to be accessed.