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