1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970
|
/**
* This module provides an implementation of a subset of the W3C [Web Performance APIs](https://w3c.github.io/perf-timing-primer/) as well as additional APIs for
* Node.js-specific performance measurements.
*
* Node.js supports the following [Web Performance APIs](https://w3c.github.io/perf-timing-primer/):
*
* * [High Resolution Time](https://www.w3.org/TR/hr-time-2)
* * [Performance Timeline](https://w3c.github.io/performance-timeline/)
* * [User Timing](https://www.w3.org/TR/user-timing/)
* * [Resource Timing](https://www.w3.org/TR/resource-timing-2/)
*
* ```js
* import { PerformanceObserver, performance } from 'node:perf_hooks';
*
* const obs = new PerformanceObserver((items) => {
* console.log(items.getEntries()[0].duration);
* performance.clearMarks();
* });
* obs.observe({ type: 'measure' });
* performance.measure('Start to Now');
*
* performance.mark('A');
* doSomeLongRunningProcess(() => {
* performance.measure('A to Now', 'A');
*
* performance.mark('B');
* performance.measure('A to B', 'A', 'B');
* });
* ```
* @see [source](https://github.com/nodejs/node/blob/v22.x/lib/perf_hooks.js)
*/
declare module "perf_hooks" {
import { AsyncResource } from "node:async_hooks";
type EntryType =
| "dns" // Node.js only
| "function" // Node.js only
| "gc" // Node.js only
| "http2" // Node.js only
| "http" // Node.js only
| "mark" // available on the Web
| "measure" // available on the Web
| "net" // Node.js only
| "node" // Node.js only
| "resource"; // available on the Web
interface NodeGCPerformanceDetail {
/**
* When `performanceEntry.entryType` is equal to 'gc', the `performance.kind` property identifies
* the type of garbage collection operation that occurred.
* See perf_hooks.constants for valid values.
*/
readonly kind?: number | undefined;
/**
* When `performanceEntry.entryType` is equal to 'gc', the `performance.flags`
* property contains additional information about garbage collection operation.
* See perf_hooks.constants for valid values.
*/
readonly flags?: number | undefined;
}
/**
* The constructor of this class is not exposed to users directly.
* @since v8.5.0
*/
class PerformanceEntry {
protected constructor();
/**
* The total number of milliseconds elapsed for this entry. This value will not
* be meaningful for all Performance Entry types.
* @since v8.5.0
*/
readonly duration: number;
/**
* The name of the performance entry.
* @since v8.5.0
*/
readonly name: string;
/**
* The high resolution millisecond timestamp marking the starting time of the
* Performance Entry.
* @since v8.5.0
*/
readonly startTime: number;
/**
* The type of the performance entry. It may be one of:
*
* * `'node'` (Node.js only)
* * `'mark'` (available on the Web)
* * `'measure'` (available on the Web)
* * `'gc'` (Node.js only)
* * `'function'` (Node.js only)
* * `'http2'` (Node.js only)
* * `'http'` (Node.js only)
* @since v8.5.0
*/
readonly entryType: EntryType;
/**
* Additional detail specific to the `entryType`.
* @since v16.0.0
*/
readonly detail?: NodeGCPerformanceDetail | unknown | undefined; // TODO: Narrow this based on entry type.
toJSON(): any;
}
/**
* Exposes marks created via the `Performance.mark()` method.
* @since v18.2.0, v16.17.0
*/
class PerformanceMark extends PerformanceEntry {
readonly duration: 0;
readonly entryType: "mark";
}
/**
* Exposes measures created via the `Performance.measure()` method.
*
* The constructor of this class is not exposed to users directly.
* @since v18.2.0, v16.17.0
*/
class PerformanceMeasure extends PerformanceEntry {
readonly entryType: "measure";
}
interface UVMetrics {
/**
* Number of event loop iterations.
*/
readonly loopCount: number;
/**
* Number of events that have been processed by the event handler.
*/
readonly events: number;
/**
* Number of events that were waiting to be processed when the event provider was called.
*/
readonly eventsWaiting: number;
}
/**
* _This property is an extension by Node.js. It is not available in Web browsers._
*
* Provides timing details for Node.js itself. The constructor of this class
* is not exposed to users.
* @since v8.5.0
*/
class PerformanceNodeTiming extends PerformanceEntry {
readonly entryType: "node";
/**
* The high resolution millisecond timestamp at which the Node.js process
* completed bootstrapping. If bootstrapping has not yet finished, the property
* has the value of -1.
* @since v8.5.0
*/
readonly bootstrapComplete: number;
/**
* The high resolution millisecond timestamp at which the Node.js environment was
* initialized.
* @since v8.5.0
*/
readonly environment: number;
/**
* The high resolution millisecond timestamp of the amount of time the event loop
* has been idle within the event loop's event provider (e.g. `epoll_wait`). This
* does not take CPU usage into consideration. If the event loop has not yet
* started (e.g., in the first tick of the main script), the property has the
* value of 0.
* @since v14.10.0, v12.19.0
*/
readonly idleTime: number;
/**
* The high resolution millisecond timestamp at which the Node.js event loop
* exited. If the event loop has not yet exited, the property has the value of -1\.
* It can only have a value of not -1 in a handler of the `'exit'` event.
* @since v8.5.0
*/
readonly loopExit: number;
/**
* The high resolution millisecond timestamp at which the Node.js event loop
* started. If the event loop has not yet started (e.g., in the first tick of the
* main script), the property has the value of -1.
* @since v8.5.0
*/
readonly loopStart: number;
/**
* The high resolution millisecond timestamp at which the Node.js process was initialized.
* @since v8.5.0
*/
readonly nodeStart: number;
/**
* This is a wrapper to the `uv_metrics_info` function.
* It returns the current set of event loop metrics.
*
* It is recommended to use this property inside a function whose execution was
* scheduled using `setImmediate` to avoid collecting metrics before finishing all
* operations scheduled during the current loop iteration.
* @since v22.8.0, v20.18.0
*/
readonly uvMetricsInfo: UVMetrics;
/**
* The high resolution millisecond timestamp at which the V8 platform was
* initialized.
* @since v8.5.0
*/
readonly v8Start: number;
}
interface EventLoopUtilization {
idle: number;
active: number;
utilization: number;
}
/**
* @param utilization1 The result of a previous call to `eventLoopUtilization()`.
* @param utilization2 The result of a previous call to `eventLoopUtilization()` prior to `utilization1`.
*/
type EventLoopUtilityFunction = (
utilization1?: EventLoopUtilization,
utilization2?: EventLoopUtilization,
) => EventLoopUtilization;
interface MarkOptions {
/**
* Additional optional detail to include with the mark.
*/
detail?: unknown | undefined;
/**
* An optional timestamp to be used as the mark time.
* @default `performance.now()`
*/
startTime?: number | undefined;
}
interface MeasureOptions {
/**
* Additional optional detail to include with the mark.
*/
detail?: unknown | undefined;
/**
* Duration between start and end times.
*/
duration?: number | undefined;
/**
* Timestamp to be used as the end time, or a string identifying a previously recorded mark.
*/
end?: number | string | undefined;
/**
* Timestamp to be used as the start time, or a string identifying a previously recorded mark.
*/
start?: number | string | undefined;
}
interface TimerifyOptions {
/**
* A histogram object created using `perf_hooks.createHistogram()` that will record runtime
* durations in nanoseconds.
*/
histogram?: RecordableHistogram | undefined;
}
interface Performance {
/**
* If `name` is not provided, removes all `PerformanceMark` objects from the Performance Timeline.
* If `name` is provided, removes only the named mark.
* @since v8.5.0
*/
clearMarks(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.
* @since v16.7.0
*/
clearMeasures(name?: string): void;
/**
* If `name` is not provided, removes all `PerformanceResourceTiming` objects from the Resource Timeline.
* If `name` is provided, removes only the named resource.
* @since v18.2.0, v16.17.0
*/
clearResourceTimings(name?: string): void;
/**
* 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.
*/
eventLoopUtilization: EventLoopUtilityFunction;
/**
* 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()`.
* @since v16.7.0
*/
getEntries(): 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`.
* @param name
* @param type
* @since v16.7.0
*/
getEntriesByName(name: string, type?: EntryType): PerformanceEntry[];
/**
* Returns a list of `PerformanceEntry` objects in chronological order with respect to `performanceEntry.startTime`
* whose `performanceEntry.entryType` is equal to `type`.
* @param type
* @since v16.7.0
*/
getEntriesByType(type: EntryType): PerformanceEntry[];
/**
* 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.
*
* The created `PerformanceMark` entry is put in the global Performance Timeline and can be queried with
* `performance.getEntries`, `performance.getEntriesByName`, and `performance.getEntriesByType`. When the observation is
* performed, the entries should be cleared from the global Performance Timeline manually with `performance.clearMarks`.
* @param name
*/
mark(name: string, options?: MarkOptions): PerformanceMark;
/**
* Creates a new `PerformanceResourceTiming` entry in the Resource Timeline.
* A `PerformanceResourceTiming` is a subclass of `PerformanceEntry` whose `performanceEntry.entryType` is always `'resource'`.
* Performance resources are used to mark moments in the Resource Timeline.
* @param timingInfo [Fetch Timing Info](https://fetch.spec.whatwg.org/#fetch-timing-info)
* @param requestedUrl The resource url
* @param initiatorType The initiator name, e.g: 'fetch'
* @param global
* @param cacheMode The cache mode must be an empty string ('') or 'local'
* @param bodyInfo [Fetch Response Body Info](https://fetch.spec.whatwg.org/#response-body-info)
* @param responseStatus The response's status code
* @param deliveryType The delivery type. Default: ''.
* @since v18.2.0, v16.17.0
*/
markResourceTiming(
timingInfo: object,
requestedUrl: string,
initiatorType: string,
global: object,
cacheMode: "" | "local",
bodyInfo: object,
responseStatus: number,
deliveryType?: string,
): PerformanceResourceTiming;
/**
* 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.
* @param name
* @param startMark
* @param endMark
* @return The PerformanceMeasure entry that was created
*/
measure(name: string, startMark?: string, endMark?: string): PerformanceMeasure;
measure(name: string, options: MeasureOptions): PerformanceMeasure;
/**
* _This property is an extension by Node.js. It is not available in Web browsers._
*
* An instance of the `PerformanceNodeTiming` class that provides performance metrics for specific Node.js operational milestones.
* @since v8.5.0
*/
readonly nodeTiming: PerformanceNodeTiming;
/**
* Returns the current high resolution millisecond timestamp, where 0 represents the start of the current `node` process.
* @since v8.5.0
*/
now(): number;
/**
* Sets the global performance resource timing buffer size to the specified number of "resource" type performance entry objects.
*
* By default the max buffer size is set to 250.
* @since v18.8.0
*/
setResourceTimingBufferSize(maxSize: number): void;
/**
* The [`timeOrigin`](https://w3c.github.io/hr-time/#dom-performance-timeorigin) specifies the high resolution millisecond timestamp
* at which the current `node` process began, measured in Unix time.
* @since v8.5.0
*/
readonly timeOrigin: number;
/**
* _This property is an extension by Node.js. It is not available in Web browsers._
*
* 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.
*
* ```js
* import {
* performance,
* PerformanceObserver,
* } from 'node:perf_hooks';
*
* function someFunction() {
* console.log('hello world');
* }
*
* const wrapped = performance.timerify(someFunction);
*
* const obs = new PerformanceObserver((list) => {
* console.log(list.getEntries()[0].duration);
*
* performance.clearMarks();
* performance.clearMeasures();
* obs.disconnect();
* });
* obs.observe({ entryTypes: ['function'] });
*
* // A performance timeline entry will be created
* wrapped();
* ```
*
* If the wrapped function returns a promise, a finally handler will be attached to the promise and the duration will be reported
* once the finally handler is invoked.
* @param fn
*/
timerify<T extends (...params: any[]) => any>(fn: T, options?: TimerifyOptions): T;
/**
* An object which is JSON representation of the performance object. It is similar to
* [`window.performance.toJSON`](https://developer.mozilla.org/en-US/docs/Web/API/Performance/toJSON) in browsers.
* @since v16.1.0
*/
toJSON(): any;
}
class PerformanceObserverEntryList {
/**
* Returns a list of `PerformanceEntry` objects in chronological order
* with respect to `performanceEntry.startTime`.
*
* ```js
* import {
* performance,
* PerformanceObserver,
* } from 'node:perf_hooks';
*
* const obs = new PerformanceObserver((perfObserverList, observer) => {
* console.log(perfObserverList.getEntries());
*
* * [
* * PerformanceEntry {
* * name: 'test',
* * entryType: 'mark',
* * startTime: 81.465639,
* * duration: 0,
* * detail: null
* * },
* * PerformanceEntry {
* * name: 'meow',
* * entryType: 'mark',
* * startTime: 81.860064,
* * duration: 0,
* * detail: null
* * }
* * ]
*
* performance.clearMarks();
* performance.clearMeasures();
* observer.disconnect();
* });
* obs.observe({ type: 'mark' });
*
* performance.mark('test');
* performance.mark('meow');
* ```
* @since v8.5.0
*/
getEntries(): 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`.
*
* ```js
* import {
* performance,
* PerformanceObserver,
* } from 'node:perf_hooks';
*
* const obs = new PerformanceObserver((perfObserverList, observer) => {
* console.log(perfObserverList.getEntriesByName('meow'));
*
* * [
* * PerformanceEntry {
* * name: 'meow',
* * entryType: 'mark',
* * startTime: 98.545991,
* * duration: 0,
* * detail: null
* * }
* * ]
*
* console.log(perfObserverList.getEntriesByName('nope')); // []
*
* console.log(perfObserverList.getEntriesByName('test', 'mark'));
*
* * [
* * PerformanceEntry {
* * name: 'test',
* * entryType: 'mark',
* * startTime: 63.518931,
* * duration: 0,
* * detail: null
* * }
* * ]
*
* console.log(perfObserverList.getEntriesByName('test', 'measure')); // []
*
* performance.clearMarks();
* performance.clearMeasures();
* observer.disconnect();
* });
* obs.observe({ entryTypes: ['mark', 'measure'] });
*
* performance.mark('test');
* performance.mark('meow');
* ```
* @since v8.5.0
*/
getEntriesByName(name: string, type?: EntryType): PerformanceEntry[];
/**
* Returns a list of `PerformanceEntry` objects in chronological order
* with respect to `performanceEntry.startTime` whose `performanceEntry.entryType` is equal to `type`.
*
* ```js
* import {
* performance,
* PerformanceObserver,
* } from 'node:perf_hooks';
*
* const obs = new PerformanceObserver((perfObserverList, observer) => {
* console.log(perfObserverList.getEntriesByType('mark'));
*
* * [
* * PerformanceEntry {
* * name: 'test',
* * entryType: 'mark',
* * startTime: 55.897834,
* * duration: 0,
* * detail: null
* * },
* * PerformanceEntry {
* * name: 'meow',
* * entryType: 'mark',
* * startTime: 56.350146,
* * duration: 0,
* * detail: null
* * }
* * ]
*
* performance.clearMarks();
* performance.clearMeasures();
* observer.disconnect();
* });
* obs.observe({ type: 'mark' });
*
* performance.mark('test');
* performance.mark('meow');
* ```
* @since v8.5.0
*/
getEntriesByType(type: EntryType): PerformanceEntry[];
}
type PerformanceObserverCallback = (list: PerformanceObserverEntryList, observer: PerformanceObserver) => void;
/**
* @since v8.5.0
*/
class PerformanceObserver extends AsyncResource {
constructor(callback: PerformanceObserverCallback);
/**
* Disconnects the `PerformanceObserver` instance from all notifications.
* @since v8.5.0
*/
disconnect(): void;
/**
* Subscribes the `PerformanceObserver` instance to notifications of new `PerformanceEntry` instances identified either by `options.entryTypes` or `options.type`:
*
* ```js
* import {
* performance,
* PerformanceObserver,
* } from 'node:perf_hooks';
*
* const obs = new PerformanceObserver((list, observer) => {
* // Called once asynchronously. `list` contains three items.
* });
* obs.observe({ type: 'mark' });
*
* for (let n = 0; n < 3; n++)
* performance.mark(`test${n}`);
* ```
* @since v8.5.0
*/
observe(
options:
| {
entryTypes: readonly EntryType[];
buffered?: boolean | undefined;
}
| {
type: EntryType;
buffered?: boolean | undefined;
},
): void;
/**
* @since v16.0.0
* @returns Current list of entries stored in the performance observer, emptying it out.
*/
takeRecords(): PerformanceEntry[];
}
/**
* Provides detailed network timing data regarding the loading of an application's resources.
*
* The constructor of this class is not exposed to users directly.
* @since v18.2.0, v16.17.0
*/
class PerformanceResourceTiming extends PerformanceEntry {
readonly entryType: "resource";
protected constructor();
/**
* The high resolution millisecond timestamp at immediately before dispatching the `fetch`
* request. If the resource is not intercepted by a worker the property will always return 0.
* @since v18.2.0, v16.17.0
*/
readonly workerStart: number;
/**
* The high resolution millisecond timestamp that represents the start time of the fetch which
* initiates the redirect.
* @since v18.2.0, v16.17.0
*/
readonly redirectStart: number;
/**
* The high resolution millisecond timestamp that will be created immediately after receiving
* the last byte of the response of the last redirect.
* @since v18.2.0, v16.17.0
*/
readonly redirectEnd: number;
/**
* The high resolution millisecond timestamp immediately before the Node.js starts to fetch the resource.
* @since v18.2.0, v16.17.0
*/
readonly fetchStart: number;
/**
* The high resolution millisecond timestamp immediately before the Node.js starts the domain name lookup
* for the resource.
* @since v18.2.0, v16.17.0
*/
readonly domainLookupStart: number;
/**
* The high resolution millisecond timestamp representing the time immediately after the Node.js finished
* the domain name lookup for the resource.
* @since v18.2.0, v16.17.0
*/
readonly domainLookupEnd: number;
/**
* The high resolution millisecond timestamp representing the time immediately before Node.js starts to
* establish the connection to the server to retrieve the resource.
* @since v18.2.0, v16.17.0
*/
readonly connectStart: number;
/**
* The high resolution millisecond timestamp representing the time immediately after Node.js finishes
* establishing the connection to the server to retrieve the resource.
* @since v18.2.0, v16.17.0
*/
readonly connectEnd: number;
/**
* The high resolution millisecond timestamp representing the time immediately before Node.js starts the
* handshake process to secure the current connection.
* @since v18.2.0, v16.17.0
*/
readonly secureConnectionStart: number;
/**
* The high resolution millisecond timestamp representing the time immediately before Node.js receives the
* first byte of the response from the server.
* @since v18.2.0, v16.17.0
*/
readonly requestStart: number;
/**
* The high resolution millisecond timestamp representing the time immediately after Node.js receives the
* last byte of the resource or immediately before the transport connection is closed, whichever comes first.
* @since v18.2.0, v16.17.0
*/
readonly responseEnd: number;
/**
* A number representing the size (in octets) of the fetched resource. The size includes the response header
* fields plus the response payload body.
* @since v18.2.0, v16.17.0
*/
readonly transferSize: number;
/**
* A number representing the size (in octets) received from the fetch (HTTP or cache), of the payload body, before
* removing any applied content-codings.
* @since v18.2.0, v16.17.0
*/
readonly encodedBodySize: number;
/**
* A number representing the size (in octets) received from the fetch (HTTP or cache), of the message body, after
* removing any applied content-codings.
* @since v18.2.0, v16.17.0
*/
readonly decodedBodySize: number;
/**
* Returns a `object` that is the JSON representation of the `PerformanceResourceTiming` object
* @since v18.2.0, v16.17.0
*/
toJSON(): any;
}
namespace constants {
const NODE_PERFORMANCE_GC_MAJOR: number;
const NODE_PERFORMANCE_GC_MINOR: number;
const NODE_PERFORMANCE_GC_INCREMENTAL: number;
const NODE_PERFORMANCE_GC_WEAKCB: number;
const NODE_PERFORMANCE_GC_FLAGS_NO: number;
const NODE_PERFORMANCE_GC_FLAGS_CONSTRUCT_RETAINED: number;
const NODE_PERFORMANCE_GC_FLAGS_FORCED: number;
const NODE_PERFORMANCE_GC_FLAGS_SYNCHRONOUS_PHANTOM_PROCESSING: number;
const NODE_PERFORMANCE_GC_FLAGS_ALL_AVAILABLE_GARBAGE: number;
const NODE_PERFORMANCE_GC_FLAGS_ALL_EXTERNAL_MEMORY: number;
const NODE_PERFORMANCE_GC_FLAGS_SCHEDULE_IDLE: number;
}
const performance: Performance;
interface EventLoopMonitorOptions {
/**
* The sampling rate in milliseconds.
* Must be greater than zero.
* @default 10
*/
resolution?: number | undefined;
}
interface Histogram {
/**
* The number of samples recorded by the histogram.
* @since v17.4.0, v16.14.0
*/
readonly count: number;
/**
* The number of samples recorded by the histogram.
* v17.4.0, v16.14.0
*/
readonly countBigInt: bigint;
/**
* The number of times the event loop delay exceeded the maximum 1 hour event
* loop delay threshold.
* @since v11.10.0
*/
readonly exceeds: number;
/**
* The number of times the event loop delay exceeded the maximum 1 hour event loop delay threshold.
* @since v17.4.0, v16.14.0
*/
readonly exceedsBigInt: bigint;
/**
* The maximum recorded event loop delay.
* @since v11.10.0
*/
readonly max: number;
/**
* The maximum recorded event loop delay.
* v17.4.0, v16.14.0
*/
readonly maxBigInt: number;
/**
* The mean of the recorded event loop delays.
* @since v11.10.0
*/
readonly mean: number;
/**
* The minimum recorded event loop delay.
* @since v11.10.0
*/
readonly min: number;
/**
* The minimum recorded event loop delay.
* v17.4.0, v16.14.0
*/
readonly minBigInt: bigint;
/**
* Returns the value at the given percentile.
* @since v11.10.0
* @param percentile A percentile value in the range (0, 100].
*/
percentile(percentile: number): number;
/**
* Returns the value at the given percentile.
* @since v17.4.0, v16.14.0
* @param percentile A percentile value in the range (0, 100].
*/
percentileBigInt(percentile: number): bigint;
/**
* Returns a `Map` object detailing the accumulated percentile distribution.
* @since v11.10.0
*/
readonly percentiles: Map<number, number>;
/**
* Returns a `Map` object detailing the accumulated percentile distribution.
* @since v17.4.0, v16.14.0
*/
readonly percentilesBigInt: Map<bigint, bigint>;
/**
* Resets the collected histogram data.
* @since v11.10.0
*/
reset(): void;
/**
* The standard deviation of the recorded event loop delays.
* @since v11.10.0
*/
readonly stddev: number;
}
interface IntervalHistogram extends Histogram {
/**
* Enables the update interval timer. Returns `true` if the timer was
* started, `false` if it was already started.
* @since v11.10.0
*/
enable(): boolean;
/**
* Disables the update interval timer. Returns `true` if the timer was
* stopped, `false` if it was already stopped.
* @since v11.10.0
*/
disable(): boolean;
}
interface RecordableHistogram extends Histogram {
/**
* @since v15.9.0, v14.18.0
* @param val The amount to record in the histogram.
*/
record(val: number | bigint): void;
/**
* Calculates the amount of time (in nanoseconds) that has passed since the
* previous call to `recordDelta()` and records that amount in the histogram.
* @since v15.9.0, v14.18.0
*/
recordDelta(): void;
/**
* Adds the values from `other` to this histogram.
* @since v17.4.0, v16.14.0
*/
add(other: RecordableHistogram): void;
}
/**
* _This property is an extension by Node.js. It is not available in Web browsers._
*
* Creates an `IntervalHistogram` object that samples and reports the event loop
* delay over time. The delays will be reported in nanoseconds.
*
* Using a timer to detect approximate event loop delay works because the
* execution of timers is tied specifically to the lifecycle of the libuv
* event loop. That is, a delay in the loop will cause a delay in the execution
* of the timer, and those delays are specifically what this API is intended to
* detect.
*
* ```js
* import { monitorEventLoopDelay } from 'node:perf_hooks';
* const h = monitorEventLoopDelay({ resolution: 20 });
* h.enable();
* // Do something.
* h.disable();
* console.log(h.min);
* console.log(h.max);
* console.log(h.mean);
* console.log(h.stddev);
* console.log(h.percentiles);
* console.log(h.percentile(50));
* console.log(h.percentile(99));
* ```
* @since v11.10.0
*/
function monitorEventLoopDelay(options?: EventLoopMonitorOptions): IntervalHistogram;
interface CreateHistogramOptions {
/**
* The minimum recordable value. Must be an integer value greater than 0.
* @default 1
*/
min?: number | bigint | undefined;
/**
* The maximum recordable value. Must be an integer value greater than min.
* @default Number.MAX_SAFE_INTEGER
*/
max?: number | bigint | undefined;
/**
* The number of accuracy digits. Must be a number between 1 and 5.
* @default 3
*/
figures?: number | undefined;
}
/**
* Returns a `RecordableHistogram`.
* @since v15.9.0, v14.18.0
*/
function createHistogram(options?: CreateHistogramOptions): RecordableHistogram;
import {
performance as _performance,
PerformanceEntry as _PerformanceEntry,
PerformanceMark as _PerformanceMark,
PerformanceMeasure as _PerformanceMeasure,
PerformanceObserver as _PerformanceObserver,
PerformanceObserverEntryList as _PerformanceObserverEntryList,
PerformanceResourceTiming as _PerformanceResourceTiming,
} from "perf_hooks";
global {
/**
* `PerformanceEntry` is a global reference for `import { PerformanceEntry } from 'node:perf_hooks'`
* @see https://nodejs.org/docs/latest-v22.x/api/globals.html#performanceentry
* @since v19.0.0
*/
var PerformanceEntry: typeof globalThis extends {
onmessage: any;
PerformanceEntry: infer T;
} ? T
: typeof _PerformanceEntry;
/**
* `PerformanceMark` is a global reference for `import { PerformanceMark } from 'node:perf_hooks'`
* @see https://nodejs.org/docs/latest-v22.x/api/globals.html#performancemark
* @since v19.0.0
*/
var PerformanceMark: typeof globalThis extends {
onmessage: any;
PerformanceMark: infer T;
} ? T
: typeof _PerformanceMark;
/**
* `PerformanceMeasure` is a global reference for `import { PerformanceMeasure } from 'node:perf_hooks'`
* @see https://nodejs.org/docs/latest-v22.x/api/globals.html#performancemeasure
* @since v19.0.0
*/
var PerformanceMeasure: typeof globalThis extends {
onmessage: any;
PerformanceMeasure: infer T;
} ? T
: typeof _PerformanceMeasure;
/**
* `PerformanceObserver` is a global reference for `import { PerformanceObserver } from 'node:perf_hooks'`
* @see https://nodejs.org/docs/latest-v22.x/api/globals.html#performanceobserver
* @since v19.0.0
*/
var PerformanceObserver: typeof globalThis extends {
onmessage: any;
PerformanceObserver: infer T;
} ? T
: typeof _PerformanceObserver;
/**
* `PerformanceObserverEntryList` is a global reference for `import { PerformanceObserverEntryList } from 'node:perf_hooks'`
* @see https://nodejs.org/docs/latest-v22.x/api/globals.html#performanceobserverentrylist
* @since v19.0.0
*/
var PerformanceObserverEntryList: typeof globalThis extends {
onmessage: any;
PerformanceObserverEntryList: infer T;
} ? T
: typeof _PerformanceObserverEntryList;
/**
* `PerformanceResourceTiming` is a global reference for `import { PerformanceResourceTiming } from 'node:perf_hooks'`
* @see https://nodejs.org/docs/latest-v22.x/api/globals.html#performanceresourcetiming
* @since v19.0.0
*/
var PerformanceResourceTiming: typeof globalThis extends {
onmessage: any;
PerformanceResourceTiming: infer T;
} ? T
: typeof _PerformanceResourceTiming;
/**
* `performance` is a global reference for `import { performance } from 'node:perf_hooks'`
* @see https://nodejs.org/docs/latest-v22.x/api/globals.html#performance
* @since v16.0.0
*/
var performance: typeof globalThis extends {
onmessage: any;
performance: infer T;
} ? T
: typeof _performance;
}
}
declare module "node:perf_hooks" {
export * from "perf_hooks";
}
|