CHANGELOG.md

   1 # Changelog
   2
   3 All notable changes to this project will be documented in this file.
   4
   5 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
   6 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
   7
   8 ## [Unreleased]
   9
  10 ### Fixed
  11
  12 - Do not pre-choose in WRR worker choice strategy to avoid bias.
  13 - Avoid array out of bound in worker choice strategies after worker node removal.
  14
  15 ## [2.6.39] - 2023-08-30
  16
  17 ### Fixed
  18
  19 - Fix race condition in worker choice strategies at worker node info querying while not yet initialized .
  20
  21 ## [2.6.38] - 2023-08-30
  22
  23 ### Added
  24
  25 - Bundle typescript types declaration into one file.
  26
  27 ### Changed
  28
  29 - Improve interleaved weighted round robin worker choice strategy implementation.
  30
  31 ## [2.6.37] - 2023-08-28
  32
  33 ### Fixed
  34
  35 - Ensure unused worker usage statistics are deleted at runtime.
  36
  37 ### Changed
  38
  39 - Rename worker choice strategy options `choiceRetries` to `retries`.
  40 - Avoid unnecessary branching in worker choice strategies.
  41
  42 ## [2.6.36] - 2023-08-27
  43
  44 ### Fixed
  45
  46 - Fix pool `execute()` arguments check.
  47
  48 ### Changed
  49
  50 - Make continuous tasks stealing algorithm less aggressive.
  51 - Fine tune tasks stealing algorithm under back pressure.
  52
  53 ## [2.6.35] - 2023-08-25
  54
  55 ### Fixed
  56
  57 - Don't account worker usage statistics for tasks that have failed.
  58 - Fix pool information runtime and wait time median computation.
  59
  60 ### Changed
  61
  62 - Update simple moving average implementation to use a circular buffer.
  63 - Update simple moving median implementation to use a circular buffer.
  64 - Account for stolen tasks in worker usage statistics and pool information.
  65
  66 ### Added
  67
  68 - Continuous tasks stealing algorithm.
  69
  70 ## [2.6.34] - 2023-08-24
  71
  72 ### Fixes
  73
  74 - Avoid cascading tasks stealing under back pressure.
  75
  76 ### Changed
  77
  78 - Add fastpath to queued tasks rescheduling.
  79
  80 ## [2.6.33] - 2023-08-24
  81
  82 ### Fixed
  83
  84 - Fix queued tasks rescheduling.
  85
  86 ### Changed
  87
  88 - Rename tasks queue options `queueMaxSize` to `size`.
  89
  90 ### Added
  91
  92 - Task stealing scheduling algorithm if tasks queueing is enabled.
  93
  94 ## [2.6.32] - 2023-08-23
  95
  96 ### Fixed
  97
  98 - Ensure no task can be executed when the pool is destroyed.
  99
 100 ### Added
 101
 102 - Add `queueMaxSize` option to tasks queue options.
 103 - Add O(1) deque implementation implemented with doubly linked list and use it for tasks queueing.
 104 - Add tasks stealing algorithm when a worker node queue is back pressured if tasks queueing is enabled.
 105
 106 ## [2.6.31] - 2023-08-20
 107
 108 ### Fixed
 109
 110 - Fix worker choice strategy retries mechanism in some edge cases.
 111
 112 ### Changed
 113
 114 - Make orthogonal worker choice strategies tasks distribution and created dynamic worker usage.
 115 - Remove the experimental status of the `LEAST_ELU` worker choice strategy.
 116
 117 ## [2.6.30] - 2023-08-19
 118
 119 ### Fixed
 120
 121 - Ensure pool event `backPressure` is emitted.
 122 - Ensure pool event `full` is emitted only once.
 123 - Ensure worker node cannot be instantiated without proper arguments.
 124
 125 ## [2.6.29] - 2023-08-18
 126
 127 ### Fixed
 128
 129 - Fix race condition between ready and task functions worker message handling at startup.
 130 - Fix duplicate task function worker usage statistics computation per task function.
 131 - Update task function worker usage statistics if and only if there's at least two different task functions.
 132 - Fix race condition at task function worker usage executing task computation leading to negative value.
 133
 134 ### Added
 135
 136 - Add back pressure detection on the worker node queue. Event `backPressure` is emitted when all worker node queues are full (worker node queue size >= poolMaxSize^2).
 137 - Use back pressure detection in worker choice strategies.
 138 - Add worker choice strategies retries mechanism if no worker is eligible.
 139
 140 ## [2.6.28] - 2023-08-16
 141
 142 ### Fixed
 143
 144 - Ensure pool workers are properly initialized.
 145
 146 ### Added
 147
 148 - HTTP server pool examples: express-cluster, express-hybrid.
 149
 150 ### Changed
 151
 152 - Remove now useless branching in worker hot code path.
 153
 154 ## [2.6.27] - 2023-08-15
 155
 156 ### Fixed
 157
 158 - Add `KillHandler` type definition to exported types.
 159
 160 ### Added
 161
 162 - Add `destroy` event to pool API.
 163
 164 ## [2.6.26] - 2023-08-15
 165
 166 ### Added
 167
 168 - Add kill handler to worker options allowing to execute custom code when worker is killed.
 169 - Add `listTaskFunctions()` method to pool API.
 170 - SMTP server pool example: nodemailer.
 171
 172 ## [2.6.25] - 2023-08-13
 173
 174 ### Added
 175
 176 - HTTP server pool examples: fastify-cluster, fastify-hybrid.
 177 - WebSocket server pool examples: ws-cluster, ws-hybrid.
 178
 179 ## [2.6.24] - 2023-08-12
 180
 181 ### Added
 182
 183 - Add array of transferable objects to the `execute()` method arguments.
 184 - WebSocket server pool examples: ws-worker_threads.
 185
 186 ## [2.6.23] - 2023-08-11
 187
 188 ### Fixed
 189
 190 - Fix pool busyness semantic when tasks queueing is enabled: the pool is busy when the number of executing tasks on each worker has reached the maximum tasks concurrency per worker.
 191
 192 ### Added
 193
 194 - HTTP client pool examples: fetch, node-fetch and axios with multiple task functions.
 195 - HTTP server pool examples: express-worker_threads, fastify-worker_threads.
 196
 197 ## [2.6.22] - 2023-08-10
 198
 199 ### Fixed
 200
 201 - Add missing `types` field to package.json `exports`.
 202
 203 ### Changed
 204
 205 - Structure markdown documentation (PR #811).
 206
 207 ## [2.6.21] - 2023-08-03
 208
 209 ### Changed
 210
 211 - Improve code documentation.
 212 - Code refactoring and cleanup for better maintainability and readability.
 213
 214 ## [2.6.20] - 2023-07-21
 215
 216 ### Fixed
 217
 218 - Fix queued tasks redistribution on error task execution starvation.
 219 - Ensure tasks queueing per worker condition is untangled from the pool busyness semantic.
 220
 221 ### Changed
 222
 223 - Drastically reduce lookups by worker in the worker nodes.
 224
 225 ## [2.6.19] - 2023-07-20
 226
 227 ### Added
 228
 229 - Dedicated internal communication channel for worker_threads pools.
 230
 231 ## [2.6.18] - 2023-07-19
 232
 233 ### Changed
 234
 235 - Code refactoring and cleanup for better maintainability and readability. Bundle size is a bit smaller.
 236
 237 ## [2.6.17] - 2023-07-16
 238
 239 ### Added
 240
 241 - Add `listTaskFunctions()` method to worker API.
 242
 243 ## [2.6.16] - 2023-07-12
 244
 245 ### Fixed
 246
 247 - Fix pool startup detection.
 248 - Fix worker task functions handling.
 249
 250 ## [2.6.15] - 2023-07-11
 251
 252 ### Added
 253
 254 - Take into account worker node readiness in worker choice strategies.
 255
 256 ## [2.6.14] - 2023-07-10
 257
 258 ### Fixed
 259
 260 - Fix task function statistics tracking.
 261
 262 ## [2.6.13] - 2023-07-10
 263
 264 ### Added
 265
 266 - Add per task function statistics tracking.
 267 - Add public methods to manipulate the worker task functions at runtime.
 268
 269 ## [2.6.12] - 2023-07-09
 270
 271 ### Fixed
 272
 273 - Workaround import issue with `node:os` module in node 16.x.x.
 274
 275 ## [2.6.11] - 2023-07-09
 276
 277 ### Fixed
 278
 279 - Fix pool readiness semantic.
 280
 281 ## [2.6.10] - 2023-07-08
 282
 283 ### Fixed
 284
 285 - Ensure workers are not recreated on error at pool startup.
 286
 287 ### Added
 288
 289 - Add `ready` and `strategy` fields to pool information.
 290 - Add pool event `ready` to notify when the number of workers created in the pool has reached the maximum size expected and are ready.
 291 - Add dynamic pool sizing checks.
 292
 293 ## [2.6.9] - 2023-07-07
 294
 295 ### Fixed
 296
 297 - Recreate the right worker type on uncaught exception.
 298
 299 ### Added
 300
 301 - Add minimum and maximum to internal measurement statistics.
 302 - Add `runTime` and `waitTime` to pool information.
 303 - Check worker inactive time only on dynamic worker.
 304
 305 ## [2.6.8] - 2023-07-03
 306
 307 ### Fixed
 308
 309 - Brown paper bag release to fix version handling in pool information.
 310
 311 ## [2.6.7] - 2023-07-03
 312
 313 ### Fixed
 314
 315 - Ensure worker queued tasks at error are reassigned to other pool workers.
 316
 317 ### Added
 318
 319 - Add pool `utilization` ratio to pool information.
 320 - Add `version` to pool information.
 321 - Add worker information to worker nodes.
 322
 323 ## [2.6.6] - 2023-07-01
 324
 325 ### Added
 326
 327 - Add safe helper `availableParallelism()` to help sizing the pool.
 328
 329 ### Fixed
 330
 331 - Ensure message handler is only registered in worker.
 332
 333 ## [2.6.5] - 2023-06-27
 334
 335 ### Known issues
 336
 337 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
 338
 339 ### Fixed
 340
 341 - Artificial version bump to 2.6.5 to workaround publication issue.
 342 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
 343 - Ensure pool event is emitted before task error promise rejection.
 344 - Fix queued tasks count computation.
 345
 346 ### Removed
 347
 348 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
 349
 350 ## [2.6.4] - 2023-06-27
 351
 352 ### Known issues
 353
 354 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
 355
 356 ### Fixed
 357
 358 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
 359 - Ensure pool event is emitted before task error promise rejection.
 360 - Fix queued tasks count computation.
 361
 362 ### Removed
 363
 364 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
 365
 366 ## [2.6.3] - 2023-06-19
 367
 368 ### Fixed
 369
 370 - Ensure no tasks are queued when trying to soft kill a dynamic worker.
 371 - Update strategies internals after statistics computation.
 372
 373 ### Changed
 374
 375 - Optimize O(1) queue implementation.
 376
 377 ## [2.6.2] - 2023-06-12
 378
 379 ### Fixed
 380
 381 - Fix new worker use after creation in dynamic pool given the current worker choice strategy.
 382
 383 ## [2.6.1] - 2023-06-10
 384
 385 ### Added
 386
 387 - Add worker choice strategy documentation: [README.md](./docs/worker-choice-strategies.md).
 388
 389 ### Fixed
 390
 391 - Fix average statistics computation: ensure failed tasks are not accounted.
 392
 393 ## [2.6.0] - 2023-06-09
 394
 395 ### Added
 396
 397 - Add `LEAST_ELU` worker choice strategy (experimental).
 398 - Add tasks ELU instead of runtime support to `FAIR_SHARE` worker choice strategy.
 399
 400 ### Changed
 401
 402 - Refactor pool worker node usage internals.
 403 - Breaking change: refactor worker choice strategy statistics requirements: the syntax of the worker choice strategy options has changed.
 404 - Breaking change: pool information `info` property object fields have been renamed.
 405
 406 ### Fixed
 407
 408 - Fix wait time accounting.
 409 - Ensure worker choice strategy `LEAST_BUSY` accounts also tasks wait time.
 410 - Ensure worker choice strategy `LEAST_USED` accounts also queued tasks.
 411
 412 ## [2.5.4] - 2023-06-07
 413
 414 ### Added
 415
 416 - Add Event Loop Utilization (ELU) statistics to worker tasks usage.
 417
 418 ### Changed
 419
 420 - Compute statistics at the worker level only if needed.
 421 - Add `worker_threads` options to thread pool options.
 422
 423 ### Fixed
 424
 425 - Make the `LEAST_BUSY` strategy only relies on task runtime.
 426
 427 ## [2.5.3] - 2023-06-04
 428
 429 ### Changed
 430
 431 - Refine pool information content.
 432 - Limit pool internals public exposure.
 433
 434 ## [2.5.2] - 2023-06-02
 435
 436 ### Added
 437
 438 - Add `taskError` pool event for task execution error.
 439 - Add pool information `info` property to pool.
 440 - Emit pool information on `busy` and `full` pool events.
 441
 442 ## [2.5.1] - 2023-06-01
 443
 444 ### Added
 445
 446 - Add pool option `restartWorkerOnError` to restart worker on uncaught error. Default to `true`.
 447 - Add `error` pool event for uncaught worker error.
 448
 449 ## [2.5.0] - 2023-05-31
 450
 451 ### Added
 452
 453 - Switch pool event emitter to `EventEmitterAsyncResource`.
 454 - Add tasks wait time accounting in per worker tasks usage.
 455 - Add interleaved weighted round robin `INTERLEAVED_WEIGHTED_ROUND_ROBIN` worker choice strategy (experimental).
 456
 457 ### Changed
 458
 459 - Renamed worker choice strategy `LESS_BUSY` to `LEAST_BUSY` and `LESS_USED` to `LEAST_USED`.
 460
 461 ## [2.4.14] - 2023-05-09
 462
 463 ### Fixed
 464
 465 - Ensure no undefined task runtime can land in the tasks history.
 466 - Fix median computation implementation once again.
 467
 468 ### Added
 469
 470 - Unit tests for median and queue implementations.
 471
 472 ## [2.4.13] - 2023-05-08
 473
 474 ### Fixed
 475
 476 - Fix worker choice strategy options validation.
 477 - Fix fair share worker choice strategy internals update: ensure virtual task end timestamp is computed at task submission.
 478
 479 ## [2.4.12] - 2023-05-06
 480
 481 ### Added
 482
 483 - Support multiple task functions per worker.
 484 - Add custom worker weights support to worker choice strategies options.
 485
 486 ### Changed
 487
 488 - Use O(1) queue implementation for tasks queueing.
 489
 490 ### Fixed
 491
 492 - Fix median computation implementation.
 493 - Fix fair share worker choice strategy internals update.
 494
 495 ## [2.4.11] - 2023-04-23
 496
 497 ### Changed
 498
 499 - Optimize free worker finding in worker choice strategies.
 500
 501 ## [2.4.10] - 2023-04-15
 502
 503 ### Fixed
 504
 505 - Fix typescript type definition for task function: ensure the input data is optional.
 506 - Fix typescript type definition for pool execute(): ensure the input data is optional.
 507
 508 ## [2.4.9] - 2023-04-15
 509
 510 ### Added
 511
 512 - Add tasks queue enablement runtime setter to pool.
 513 - Add tasks queue options runtime setter to pool.
 514 - Add worker choice strategy options runtime setter to pool.
 515
 516 ### Changed
 517
 518 - Remove the tasks queuing experimental status.
 519
 520 ### Fixed
 521
 522 - Fix task function type definition and validation.
 523 - Fix worker choice strategy options handling.
 524
 525 ## [2.4.8] - 2023-04-12
 526
 527 ### Fixed
 528
 529 - Fix message between main worker and worker type definition for tasks.
 530 - Fix code documentation.
 531
 532 ## [2.4.7] - 2023-04-11
 533
 534 ### Added
 535
 536 - Add worker tasks queue options to pool options.
 537
 538 ### Fixed
 539
 540 - Fix missing documentation.
 541
 542 ## [2.4.6] - 2023-04-10
 543
 544 ### Fixed
 545
 546 - Ensure one task at a time is executed per worker with tasks queueing enabled.
 547 - Properly count worker executing tasks with tasks queueing enabled.
 548
 549 ## [2.4.5] - 2023-04-09
 550
 551 ### Added
 552
 553 - Use monotonic high resolution timer for worker tasks runtime.
 554 - Add worker tasks median runtime to statistics.
 555 - Add worker tasks queue (experimental).
 556
 557 ## [2.4.4] - 2023-04-07
 558
 559 ### Added
 560
 561 - Add `PoolEvents` enumeration and `PoolEvent` type.
 562
 563 ### Fixed
 564
 565 - Destroy worker only on alive check.
 566
 567 ## [2.4.3] - 2023-04-07
 568
 569 ### Fixed
 570
 571 - Fix typedoc generation with inheritance.
 572
 573 ## [2.4.2] - 2023-04-06
 574
 575 ### Added
 576
 577 - Add `full` event to dynamic pool.
 578 - Keep worker choice strategy in memory for conditional reuse.
 579
 580 ### Fixed
 581
 582 - Fix possible negative worker key at worker removal in worker choice strategies.
 583
 584 ## [2.4.1] - 2023-04-05
 585
 586 ### Changed
 587
 588 - Optimize worker choice strategy for dynamic pool.
 589
 590 ### Fixed
 591
 592 - Ensure dynamic pool does not alter worker choice strategy expected behavior.
 593
 594 ## [2.4.0] - 2023-04-04
 595
 596 ### Added
 597
 598 - Add `LESS_BUSY` worker choice strategy.
 599
 600 ### Changed
 601
 602 - Optimize worker storage in pool.
 603 - Optimize worker alive status check.
 604 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
 605 - Optimize `LESS_USED` worker choice strategy.
 606 - Update benchmarks versus external threads pools.
 607 - Optimize tasks usage statistics requirements for worker choice strategy.
 608
 609 ### Fixed
 610
 611 - Ensure trimmable characters are checked at pool initialization.
 612 - Fix message id integer overflow.
 613 - Fix pool worker removal in worker choice strategy internals.
 614 - Fix package publication with pnpm.
 615
 616 ## [2.4.0-3] - 2023-04-04
 617
 618 ### Added
 619
 620 - Add `LESS_BUSY` worker choice strategy.
 621
 622 ### Changed
 623
 624 - Optimize worker storage in pool.
 625 - Optimize worker alive status check.
 626 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
 627 - Optimize `LESS_USED` worker choice strategy.
 628 - Update benchmarks versus external threads pools.
 629
 630 ### Fixed
 631
 632 - Ensure trimmable characters are checked at pool initialization.
 633 - Fix message id integer overflow.
 634 - Fix pool worker removal in worker choice strategy internals.
 635 - Fix package publication with pnpm.
 636
 637 ## [2.4.0-2] - 2023-04-03
 638
 639 ### Added
 640
 641 - Add `LESS_BUSY` worker choice strategy.
 642
 643 ### Changed
 644
 645 - Optimize worker storage in pool.
 646 - Optimize worker alive status check.
 647 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
 648 - Optimize `LESS_USED` worker choice strategy.
 649
 650 ### Fixed
 651
 652 - Ensure trimmable characters are checked at pool initialization.
 653 - Fix message id integer overflow.
 654 - Fix pool worker removal in worker choice strategy internals.
 655 - Fix package publication with pnpm.
 656
 657 ## [2.4.0-1] - 2023-04-03
 658
 659 ### Added
 660
 661 - Add `LESS_BUSY` worker choice strategy.
 662
 663 ### Changed
 664
 665 - Optimize worker storage in pool.
 666 - Optimize worker alive status check.
 667 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
 668 - Optimize `LESS_USED` worker choice strategy.
 669
 670 ### Fixed
 671
 672 - Ensure trimmable characters are checked at pool initialization.
 673 - Fix message id integer overflow.
 674 - Fix pool worker removal in worker choice strategy internals.
 675
 676 ## [2.4.0-0] - 2023-04-03
 677
 678 ### Added
 679
 680 - Add `LESS_BUSY` worker choice strategy.
 681
 682 ### Changed
 683
 684 - Optimize worker storage in pool.
 685 - Optimize worker alive status check.
 686 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
 687 - Optimize `LESS_USED` worker choice strategy.
 688
 689 ### Fixed
 690
 691 - Ensure trimmable characters are checked at pool initialization.
 692 - Fix message id integer overflow.
 693 - Fix pool worker removal in worker choice strategy internals.
 694
 695 ## [2.3.10] - 2023-03-18
 696
 697 ### Fixed
 698
 699 - Fix package.json `exports` syntax for ESM and CommonJS.
 700
 701 ### Changed
 702
 703 - Permit SemVer pre-release publication.
 704
 705 ## [2.3.10-2] - 2023-03-18
 706
 707 ### Fixed
 708
 709 - Fix package.json `exports` syntax for ESM and CommonJS.
 710
 711 ## [2.3.10-1] - 2023-03-18
 712
 713 ### Changed
 714
 715 - Permit SemVer pre-release publication.
 716
 717 ## [2.3.10-0] - 2023-03-18
 718
 719 ### Fixed
 720
 721 - Fix package.json `exports` syntax for ESM and CommonJS.
 722
 723 ## [2.3.9] - 2023-03-18
 724
 725 ### Changed
 726
 727 - Introduce ESM module support along with CommonJS one.
 728
 729 ### Fixed
 730
 731 - Fix brown paper bag bug referencing the same object literal.
 732
 733 ## [2.3.8] - 2023-03-18
 734
 735 ### Changed
 736
 737 - Switch internal benchmarking code to benny.
 738 - Switch to TypeScript 5.x.x.
 739 - Switch rollup bundler plugins to core ones.
 740 - Switch to TSDoc syntax.
 741 - Enforce conventional commits.
 742
 743 ### Fixed
 744
 745 - Fix random integer generator.
 746 - Fix worker choice strategy pool type identification at initialization.
 747
 748 ## [2.3.7] - 2022-10-23
 749
 750 ### Changed
 751
 752 - Switch to open collective FOSS project funding platform.
 753 - Switch to ts-standard linter configuration on TypeScript code.
 754
 755 ### Fixed
 756
 757 - Fixed missing async on pool execute method.
 758 - Fixed typing in TypeScript example.
 759 - Fixed types in unit tests.
 760
 761 ## [2.3.6] - 2022-10-22
 762
 763 ### Changed
 764
 765 - Cleanup pool attributes and methods.
 766 - Refine error types thrown.
 767
 768 ### Fixed
 769
 770 - Fix continuous integration build on windows.
 771 - Fix code coverage reporting by using c8 instead of nyc.
 772
 773 ## [2.3.5] - 2022-10-21
 774
 775 ### Changed
 776
 777 - Improve benchmarks: add IO intensive task workload, add task size option, integrate code into linter.
 778 - Optimize tasks usage lookup implementation.
 779
 780 ### Fixed
 781
 782 - Fix missed pool event emitter type export.
 783 - Fix typedoc documentation generation.
 784
 785 ## [2.3.4] - 2022-10-17
 786
 787 ### Added
 788
 789 - Fully automate release process with release-it.
 790
 791 ### Changed
 792
 793 - Optimize fair share task scheduling algorithm implementation.
 794 - Update benchmarks versus external pools results with latest version.
 795
 796 ## [2.3.3] - 2022-10-15
 797
 798 ### Added
 799
 800 - Add support for [cluster settings](https://nodejs.org/api/cluster.html#cluster_cluster_settings) in cluster pool options.
 801
 802 ## [2.3.2] - 2022-10-14
 803
 804 ### Changed
 805
 806 - Optimize fair share worker selection strategy implementation.
 807
 808 ### Fixed
 809
 810 - Fix WRR worker selection strategy: ensure the condition triggering the round robin can be fulfilled.
 811
 812 ## [2.3.1] - 2022-10-13
 813
 814 ### Added
 815
 816 - Pool worker choice strategies:
 817   - `WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN` strategy based on weighted round robin scheduling algorithm using tasks execution time for now.
 818   - `WorkerChoiceStrategies.FAIR_SHARE` strategy based on fair share scheduling algorithm using tasks execution time for now.
 819
 820 ## [2.2.2] - 2022-10-09
 821
 822 ### Fixed
 823
 824 - Fixed `README.md` file.
 825
 826 ## [2.2.1] - 2022-10-08
 827
 828 ### Added
 829
 830 - Dynamic worker choice strategy change at runtime.
 831
 832 ## [2.2.0] - 2022-01-05
 833
 834 ### Breaking Changes
 835
 836 - Support only Node.js version 16.x.x for cluster pool: upstream cluster API have changed on that version.
 837
 838 ## [2.1.0] - 2021-08-29
 839
 840 ### Added
 841
 842 - Add an optional pool option `messageHandler` to `PoolOptions<Worker>` for registering a message handler callback on each worker.
 843
 844 ### Breaking Changes
 845
 846 - `AbstractWorker` class `maxInactiveTime`, `killBehavior` and `async` attributes have been removed in favour of the same ones in the worker options `opts` public attribute.
 847 - `AbstractWorker` class `lastTask` attribute have been renamed to `lastTaskTimestamp`.
 848 - `AbstractWorker` class `interval` attribute have been renamed to `aliveInterval`.
 849 - `AbstractWorker` class cannot be instantiated without specifying the `mainWorker` argument referencing the main worker.
 850
 851 ## [2.0.2] - 2021-05-12
 852
 853 ### Bug fixes
 854
 855 - Fix `busy` event emission on fixed pool type
 856
 857 ## [2.0.1] - 2021-03-16
 858
 859 ### Bug fixes
 860
 861 - Check if pool options are properly set.
 862 - `busy` event is emitted on all pool types.
 863
 864 ## [2.0.0] - 2021-03-01
 865
 866 ### Bug fixes
 867
 868 - Now a thread/process by default is not deleted when the task submitted take more time than maxInactiveTime configured (issue #70).
 869
 870 ### Breaking Changes
 871
 872 - `FullPool` event is now renamed to `busy`.
 873 - `maxInactiveTime` on `ThreadWorker` default behavior is now changed, if you want to keep the old behavior set `killBehavior` to `KillBehaviors.HARD`.
 874   _Find more details on our JSDoc._
 875
 876 - `maxTasks` option on `FixedThreadPool` and `DynamicThreadPool` is now removed since is no more needed.
 877
 878 - We changed some internal structures, but you shouldn't be too affected by them as these are internal changes.
 879
 880 ### Pool options types declaration merge
 881
 882 `FixedThreadPoolOptions` and `DynamicThreadPoolOptions` type declarations have been merged to `PoolOptions<Worker>`.
 883
 884 #### New `export` strategy
 885
 886 ```js
 887 // Before
 888 const DynamicThreadPool = require('poolifier/lib/dynamic')
 889 // After
 890 const { DynamicThreadPool } = require('poolifier/lib/dynamic')
 891 ```
 892
 893 But you should always prefer just using
 894
 895 ```js
 896 const { DynamicThreadPool } = require('poolifier')
 897 ```
 898
 899 #### New type definitions for input data and response
 900
 901 For cluster worker and worker-thread pools, you can now only send and receive structured-cloneable data.
 902 _This is not a limitation by poolifier but Node.js._
 903
 904 #### Public property replacements
 905
 906 `numWorkers` property is now `numberOfWorkers`
 907
 908 #### Internal (protected) properties and methods renaming
 909
 910 These properties are not intended for end users
 911
 912 - `id` => `nextMessageId`
 913
 914 These methods are not intended for end users
 915
 916 - `_chooseWorker` => `chooseWorker`
 917 - `_newWorker` => `createWorker`
 918 - `_execute` => `internalExecute`
 919 - `_chooseWorker` => `chooseWorker`
 920 - `_checkAlive` => `checkAlive`
 921 - `_run` => `run`
 922 - `_runAsync` => `runAsync`
 923
 924 ## [1.1.0] - 2020-05-21
 925
 926 ### Added
 927
 928 - ThreadWorker support async functions as option
 929 - Various external library patches
 930
 931 ## [1.0.0] - 2020-01-24
 932
 933 ### Added
 934
 935 - FixedThreadPool implementation
 936 - DynamicThreadPool implementation
 937 - WorkerThread implementation to improve developer experience