3 All notable changes to this project will be documented in this file.
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).
10 ## [2.6.45] - 2023-09-17
14 - Disable publication on GitHub packages registry on release until authentication issue is fixed.
18 - Add `startWorkers` to pool options to whether start the minimum number of workers at pool creation or not.
19 - Add `start()` method to pool API to start the minimum number of workers.
20 - Add `taskStealing` and `tasksStealingOnPressure` to tasks queue options to whether enable task stealing or not and whether enable tasks stealing on back pressure or not.
21 - Continuous internal benchmarking: https://poolifier.github.io/benchmark-results/dev/bench.
23 ## [2.6.44] - 2023-09-08
27 - Use a dedicated PAT to publish on GitHub packages registry.
31 - Publish on GitHub packages registry on release.
35 - Switch from rome to biome: [PR #1128](https://github.com/poolifier/poolifier/pull/1128).
37 ## [2.6.43] - 2023-09-08
41 - Publish on GitHub packages registry on release.
45 - Switch from rome to biome: [PR #1128](https://github.com/poolifier/poolifier/pull/1128).
47 ## [2.6.42] - 2023-09-06
51 - Optimize hot code paths implementation: avoid unnecessary branching, add and use optimized helpers (min, max), use reduce() array helper, ...
53 ## [2.6.41] - 2023-09-03
57 - Optimize worker choice strategies implementation.
59 ## [2.6.40] - 2023-09-01
63 - Do not pre-choose in WRR worker choice strategy to avoid bias.
64 - Avoid array out of bound in worker choice strategies after worker node removal.
66 ## [2.6.39] - 2023-08-30
70 - Fix race condition in worker choice strategies at worker node info querying while not yet initialized.
72 ## [2.6.38] - 2023-08-30
76 - Bundle typescript types declaration into one file.
80 - Improve interleaved weighted round robin worker choice strategy implementation.
82 ## [2.6.37] - 2023-08-28
86 - Ensure unused worker usage statistics are deleted at runtime.
90 - Rename worker choice strategy options `choiceRetries` to `retries`.
91 - Avoid unnecessary branching in worker choice strategies.
93 ## [2.6.36] - 2023-08-27
97 - Fix pool `execute()` arguments check.
101 - Make continuous tasks stealing algorithm less aggressive.
102 - Fine tune tasks stealing algorithm under back pressure.
104 ## [2.6.35] - 2023-08-25
108 - Don't account worker usage statistics for tasks that have failed.
109 - Fix pool information runtime and wait time median computation.
113 - Update simple moving average implementation to use a circular buffer.
114 - Update simple moving median implementation to use a circular buffer.
115 - Account for stolen tasks in worker usage statistics and pool information.
119 - Continuous tasks stealing algorithm.
121 ## [2.6.34] - 2023-08-24
125 - Avoid cascading tasks stealing under back pressure.
129 - Add fastpath to queued tasks rescheduling.
131 ## [2.6.33] - 2023-08-24
135 - Fix queued tasks rescheduling.
139 - Rename tasks queue options `queueMaxSize` to `size`.
143 - Task stealing scheduling algorithm if tasks queueing is enabled.
145 ## [2.6.32] - 2023-08-23
149 - Ensure no task can be executed when the pool is destroyed.
153 - Add `queueMaxSize` option to tasks queue options.
154 - Add O(1) deque implementation implemented with doubly linked list and use it for tasks queueing.
155 - Add tasks stealing algorithm when a worker node queue is back pressured if tasks queueing is enabled.
157 ## [2.6.31] - 2023-08-20
161 - Fix worker choice strategy retries mechanism in some edge cases.
165 - Make orthogonal worker choice strategies tasks distribution and created dynamic worker usage.
166 - Remove the experimental status of the `LEAST_ELU` worker choice strategy.
168 ## [2.6.30] - 2023-08-19
172 - Ensure pool event `backPressure` is emitted.
173 - Ensure pool event `full` is emitted only once.
174 - Ensure worker node cannot be instantiated without proper arguments.
176 ## [2.6.29] - 2023-08-18
180 - Fix race condition between ready and task functions worker message handling at startup.
181 - Fix duplicate task function worker usage statistics computation per task function.
182 - Update task function worker usage statistics if and only if there's at least two different task functions.
183 - Fix race condition at task function worker usage executing task computation leading to negative value.
187 - 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).
188 - Use back pressure detection in worker choice strategies.
189 - Add worker choice strategies retries mechanism if no worker is eligible.
191 ## [2.6.28] - 2023-08-16
195 - Ensure pool workers are properly initialized.
199 - HTTP server pool examples: express-cluster, express-hybrid.
203 - Remove now useless branching in worker hot code path.
205 ## [2.6.27] - 2023-08-15
209 - Add `KillHandler` type definition to exported types.
213 - Add `destroy` event to pool API.
215 ## [2.6.26] - 2023-08-15
219 - Add kill handler to worker options allowing to execute custom code when worker is killed.
220 - Add `listTaskFunctions()` method to pool API.
221 - SMTP client pool example: nodemailer.
223 ## [2.6.25] - 2023-08-13
227 - HTTP server pool examples: fastify-cluster, fastify-hybrid.
228 - WebSocket server pool examples: ws-cluster, ws-hybrid.
230 ## [2.6.24] - 2023-08-12
234 - Add array of transferable objects to the `execute()` method arguments.
235 - WebSocket server pool examples: ws-worker_threads.
237 ## [2.6.23] - 2023-08-11
241 - 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.
245 - HTTP client pool examples: fetch, node-fetch and axios with multiple task functions.
246 - HTTP server pool examples: express-worker_threads, fastify-worker_threads.
248 ## [2.6.22] - 2023-08-10
252 - Add missing `types` field to package.json `exports`.
256 - Structure markdown documentation (PR #811).
258 ## [2.6.21] - 2023-08-03
262 - Improve code documentation.
263 - Code refactoring and cleanup for better maintainability and readability.
265 ## [2.6.20] - 2023-07-21
269 - Fix queued tasks redistribution on error task execution starvation.
270 - Ensure tasks queueing per worker condition is untangled from the pool busyness semantic.
274 - Drastically reduce lookups by worker in the worker nodes.
276 ## [2.6.19] - 2023-07-20
280 - Dedicated internal communication channel for worker_threads pools.
282 ## [2.6.18] - 2023-07-19
286 - Code refactoring and cleanup for better maintainability and readability. Bundle size is a bit smaller.
288 ## [2.6.17] - 2023-07-16
292 - Add `listTaskFunctions()` method to worker API.
294 ## [2.6.16] - 2023-07-12
298 - Fix pool startup detection.
299 - Fix worker task functions handling.
301 ## [2.6.15] - 2023-07-11
305 - Take into account worker node readiness in worker choice strategies.
307 ## [2.6.14] - 2023-07-10
311 - Fix task function statistics tracking.
313 ## [2.6.13] - 2023-07-10
317 - Add per task function statistics tracking.
318 - Add public methods to manipulate the worker task functions at runtime.
320 ## [2.6.12] - 2023-07-09
324 - Workaround import issue with `node:os` module in node 16.x.x.
326 ## [2.6.11] - 2023-07-09
330 - Fix pool readiness semantic.
332 ## [2.6.10] - 2023-07-08
336 - Ensure workers are not recreated on error at pool startup.
340 - Add `ready` and `strategy` fields to pool information.
341 - Add pool event `ready` to notify when the number of workers created in the pool has reached the maximum size expected and are ready.
342 - Add dynamic pool sizing checks.
344 ## [2.6.9] - 2023-07-07
348 - Recreate the right worker type on uncaught exception.
352 - Add minimum and maximum to internal measurement statistics.
353 - Add `runTime` and `waitTime` to pool information.
354 - Check worker inactive time only on dynamic worker.
356 ## [2.6.8] - 2023-07-03
360 - Brown paper bag release to fix version handling in pool information.
362 ## [2.6.7] - 2023-07-03
366 - Ensure worker queued tasks at error are reassigned to other pool workers.
370 - Add pool `utilization` ratio to pool information.
371 - Add `version` to pool information.
372 - Add worker information to worker nodes.
374 ## [2.6.6] - 2023-07-01
378 - Add safe helper `availableParallelism()` to help sizing the pool.
382 - Ensure message handler is only registered in worker.
384 ## [2.6.5] - 2023-06-27
388 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
392 - Artificial version bump to 2.6.5 to workaround publication issue.
393 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
394 - Ensure pool event is emitted before task error promise rejection.
395 - Fix queued tasks count computation.
399 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
401 ## [2.6.4] - 2023-06-27
405 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
409 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
410 - Ensure pool event is emitted before task error promise rejection.
411 - Fix queued tasks count computation.
415 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
417 ## [2.6.3] - 2023-06-19
421 - Ensure no tasks are queued when trying to soft kill a dynamic worker.
422 - Update strategies internals after statistics computation.
426 - Optimize O(1) queue implementation.
428 ## [2.6.2] - 2023-06-12
432 - Fix new worker use after creation in dynamic pool given the current worker choice strategy.
434 ## [2.6.1] - 2023-06-10
438 - Add worker choice strategy documentation: [README.md](./docs/worker-choice-strategies.md).
442 - Fix average statistics computation: ensure failed tasks are not accounted.
444 ## [2.6.0] - 2023-06-09
448 - Add `LEAST_ELU` worker choice strategy (experimental).
449 - Add tasks ELU instead of runtime support to `FAIR_SHARE` worker choice strategy.
453 - Refactor pool worker node usage internals.
454 - Breaking change: refactor worker choice strategy statistics requirements: the syntax of the worker choice strategy options has changed.
455 - Breaking change: pool information `info` property object fields have been renamed.
459 - Fix wait time accounting.
460 - Ensure worker choice strategy `LEAST_BUSY` accounts also tasks wait time.
461 - Ensure worker choice strategy `LEAST_USED` accounts also queued tasks.
463 ## [2.5.4] - 2023-06-07
467 - Add Event Loop Utilization (ELU) statistics to worker tasks usage.
471 - Compute statistics at the worker level only if needed.
472 - Add `worker_threads` options to thread pool options.
476 - Make the `LEAST_BUSY` strategy only relies on task runtime.
478 ## [2.5.3] - 2023-06-04
482 - Refine pool information content.
483 - Limit pool internals public exposure.
485 ## [2.5.2] - 2023-06-02
489 - Add `taskError` pool event for task execution error.
490 - Add pool information `info` property to pool.
491 - Emit pool information on `busy` and `full` pool events.
493 ## [2.5.1] - 2023-06-01
497 - Add pool option `restartWorkerOnError` to restart worker on uncaught error. Default to `true`.
498 - Add `error` pool event for uncaught worker error.
500 ## [2.5.0] - 2023-05-31
504 - Switch pool event emitter to `EventEmitterAsyncResource`.
505 - Add tasks wait time accounting in per worker tasks usage.
506 - Add interleaved weighted round robin `INTERLEAVED_WEIGHTED_ROUND_ROBIN` worker choice strategy (experimental).
510 - Renamed worker choice strategy `LESS_BUSY` to `LEAST_BUSY` and `LESS_USED` to `LEAST_USED`.
512 ## [2.4.14] - 2023-05-09
516 - Ensure no undefined task runtime can land in the tasks history.
517 - Fix median computation implementation once again.
521 - Unit tests for median and queue implementations.
523 ## [2.4.13] - 2023-05-08
527 - Fix worker choice strategy options validation.
528 - Fix fair share worker choice strategy internals update: ensure virtual task end timestamp is computed at task submission.
530 ## [2.4.12] - 2023-05-06
534 - Support multiple task functions per worker.
535 - Add custom worker weights support to worker choice strategies options.
539 - Use O(1) queue implementation for tasks queueing.
543 - Fix median computation implementation.
544 - Fix fair share worker choice strategy internals update.
546 ## [2.4.11] - 2023-04-23
550 - Optimize free worker finding in worker choice strategies.
552 ## [2.4.10] - 2023-04-15
556 - Fix typescript type definition for task function: ensure the input data is optional.
557 - Fix typescript type definition for pool execute(): ensure the input data is optional.
559 ## [2.4.9] - 2023-04-15
563 - Add tasks queue enablement runtime setter to pool.
564 - Add tasks queue options runtime setter to pool.
565 - Add worker choice strategy options runtime setter to pool.
569 - Remove the tasks queuing experimental status.
573 - Fix task function type definition and validation.
574 - Fix worker choice strategy options handling.
576 ## [2.4.8] - 2023-04-12
580 - Fix message between main worker and worker type definition for tasks.
581 - Fix code documentation.
583 ## [2.4.7] - 2023-04-11
587 - Add worker tasks queue options to pool options.
591 - Fix missing documentation.
593 ## [2.4.6] - 2023-04-10
597 - Ensure one task at a time is executed per worker with tasks queueing enabled.
598 - Properly count worker executing tasks with tasks queueing enabled.
600 ## [2.4.5] - 2023-04-09
604 - Use monotonic high resolution timer for worker tasks runtime.
605 - Add worker tasks median runtime to statistics.
606 - Add worker tasks queue (experimental).
608 ## [2.4.4] - 2023-04-07
612 - Add `PoolEvents` enumeration and `PoolEvent` type.
616 - Destroy worker only on alive check.
618 ## [2.4.3] - 2023-04-07
622 - Fix typedoc generation with inheritance.
624 ## [2.4.2] - 2023-04-06
628 - Add `full` event to dynamic pool.
629 - Keep worker choice strategy in memory for conditional reuse.
633 - Fix possible negative worker key at worker removal in worker choice strategies.
635 ## [2.4.1] - 2023-04-05
639 - Optimize worker choice strategy for dynamic pool.
643 - Ensure dynamic pool does not alter worker choice strategy expected behavior.
645 ## [2.4.0] - 2023-04-04
649 - Add `LESS_BUSY` worker choice strategy.
653 - Optimize worker storage in pool.
654 - Optimize worker alive status check.
655 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
656 - Optimize `LESS_USED` worker choice strategy.
657 - Update benchmark versus external threads pools.
658 - Optimize tasks usage statistics requirements for worker choice strategy.
662 - Ensure trimmable characters are checked at pool initialization.
663 - Fix message id integer overflow.
664 - Fix pool worker removal in worker choice strategy internals.
665 - Fix package publication with pnpm.
667 ## [2.4.0-3] - 2023-04-04
671 - Add `LESS_BUSY` worker choice strategy.
675 - Optimize worker storage in pool.
676 - Optimize worker alive status check.
677 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
678 - Optimize `LESS_USED` worker choice strategy.
679 - Update benchmark versus external threads pools.
683 - Ensure trimmable characters are checked at pool initialization.
684 - Fix message id integer overflow.
685 - Fix pool worker removal in worker choice strategy internals.
686 - Fix package publication with pnpm.
688 ## [2.4.0-2] - 2023-04-03
692 - Add `LESS_BUSY` worker choice strategy.
696 - Optimize worker storage in pool.
697 - Optimize worker alive status check.
698 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
699 - Optimize `LESS_USED` worker choice strategy.
703 - Ensure trimmable characters are checked at pool initialization.
704 - Fix message id integer overflow.
705 - Fix pool worker removal in worker choice strategy internals.
706 - Fix package publication with pnpm.
708 ## [2.4.0-1] - 2023-04-03
712 - Add `LESS_BUSY` worker choice strategy.
716 - Optimize worker storage in pool.
717 - Optimize worker alive status check.
718 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
719 - Optimize `LESS_USED` worker choice strategy.
723 - Ensure trimmable characters are checked at pool initialization.
724 - Fix message id integer overflow.
725 - Fix pool worker removal in worker choice strategy internals.
727 ## [2.4.0-0] - 2023-04-03
731 - Add `LESS_BUSY` worker choice strategy.
735 - Optimize worker storage in pool.
736 - Optimize worker alive status check.
737 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
738 - Optimize `LESS_USED` worker choice strategy.
742 - Ensure trimmable characters are checked at pool initialization.
743 - Fix message id integer overflow.
744 - Fix pool worker removal in worker choice strategy internals.
746 ## [2.3.10] - 2023-03-18
750 - Fix package.json `exports` syntax for ESM and CommonJS.
754 - Permit SemVer pre-release publication.
756 ## [2.3.10-2] - 2023-03-18
760 - Fix package.json `exports` syntax for ESM and CommonJS.
762 ## [2.3.10-1] - 2023-03-18
766 - Permit SemVer pre-release publication.
768 ## [2.3.10-0] - 2023-03-18
772 - Fix package.json `exports` syntax for ESM and CommonJS.
774 ## [2.3.9] - 2023-03-18
778 - Introduce ESM module support along with CommonJS one.
782 - Fix brown paper bag bug referencing the same object literal.
784 ## [2.3.8] - 2023-03-18
788 - Switch internal benchmarking code to benny.
789 - Switch to TypeScript 5.x.x.
790 - Switch rollup bundler plugins to core ones.
791 - Switch to TSDoc syntax.
792 - Enforce conventional commits.
796 - Fix random integer generator.
797 - Fix worker choice strategy pool type identification at initialization.
799 ## [2.3.7] - 2022-10-23
803 - Switch to open collective FOSS project funding platform.
804 - Switch to ts-standard linter configuration on TypeScript code.
808 - Fixed missing async on pool execute method.
809 - Fixed typing in TypeScript example.
810 - Fixed types in unit tests.
812 ## [2.3.6] - 2022-10-22
816 - Cleanup pool attributes and methods.
817 - Refine error types thrown.
821 - Fix continuous integration build on windows.
822 - Fix code coverage reporting by using c8 instead of nyc.
824 ## [2.3.5] - 2022-10-21
828 - Improve benchmarks: add IO intensive task workload, add task size option, integrate code into linter.
829 - Optimize tasks usage lookup implementation.
833 - Fix missed pool event emitter type export.
834 - Fix typedoc documentation generation.
836 ## [2.3.4] - 2022-10-17
840 - Fully automate release process with release-it.
844 - Optimize fair share task scheduling algorithm implementation.
845 - Update benchmark versus external pools results with latest version.
847 ## [2.3.3] - 2022-10-15
851 - Add support for [cluster settings](https://nodejs.org/api/cluster.html#cluster_cluster_settings) in cluster pool options.
853 ## [2.3.2] - 2022-10-14
857 - Optimize fair share worker selection strategy implementation.
861 - Fix WRR worker selection strategy: ensure the condition triggering the round robin can be fulfilled.
863 ## [2.3.1] - 2022-10-13
867 - Pool worker choice strategies:
868 - `WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN` strategy based on weighted round robin scheduling algorithm using tasks execution time for now.
869 - `WorkerChoiceStrategies.FAIR_SHARE` strategy based on fair share scheduling algorithm using tasks execution time for now.
871 ## [2.2.2] - 2022-10-09
875 - Fixed `README.md` file.
877 ## [2.2.1] - 2022-10-08
881 - Dynamic worker choice strategy change at runtime.
883 ## [2.2.0] - 2022-01-05
887 - Support only Node.js version 16.x.x for cluster pool: upstream cluster API have changed on that version.
889 ## [2.1.0] - 2021-08-29
893 - Add an optional pool option `messageHandler` to `PoolOptions<Worker>` for registering a message handler callback on each worker.
897 - `AbstractWorker` class `maxInactiveTime`, `killBehavior` and `async` attributes have been removed in favour of the same ones in the worker options `opts` public attribute.
898 - `AbstractWorker` class `lastTask` attribute have been renamed to `lastTaskTimestamp`.
899 - `AbstractWorker` class `interval` attribute have been renamed to `aliveInterval`.
900 - `AbstractWorker` class cannot be instantiated without specifying the `mainWorker` argument referencing the main worker.
902 ## [2.0.2] - 2021-05-12
906 - Fix `busy` event emission on fixed pool type
908 ## [2.0.1] - 2021-03-16
912 - Check if pool options are properly set.
913 - `busy` event is emitted on all pool types.
915 ## [2.0.0] - 2021-03-01
919 - Now a thread/process by default is not deleted when the task submitted take more time than maxInactiveTime configured (issue #70).
923 - `FullPool` event is now renamed to `busy`.
924 - `maxInactiveTime` on `ThreadWorker` default behavior is now changed, if you want to keep the old behavior set `killBehavior` to `KillBehaviors.HARD`.
925 _Find more details on our JSDoc._
927 - `maxTasks` option on `FixedThreadPool` and `DynamicThreadPool` is now removed since is no more needed.
929 - We changed some internal structures, but you shouldn't be too affected by them as these are internal changes.
931 ### Pool options types declaration merge
933 `FixedThreadPoolOptions` and `DynamicThreadPoolOptions` type declarations have been merged to `PoolOptions<Worker>`.
935 #### New `export` strategy
939 const DynamicThreadPool = require('poolifier/lib/dynamic')
941 const { DynamicThreadPool } = require('poolifier/lib/dynamic')
944 But you should always prefer just using
947 const { DynamicThreadPool } = require('poolifier')
950 #### New type definitions for input data and response
952 For cluster worker and worker-thread pools, you can now only send and receive structured-cloneable data.
953 _This is not a limitation by poolifier but Node.js._
955 #### Public property replacements
957 `numWorkers` property is now `numberOfWorkers`
959 #### Internal (protected) properties and methods renaming
961 These properties are not intended for end users
963 - `id` => `nextMessageId`
965 These methods are not intended for end users
967 - `_chooseWorker` => `chooseWorker`
968 - `_newWorker` => `createWorker`
969 - `_execute` => `internalExecute`
970 - `_chooseWorker` => `chooseWorker`
971 - `_checkAlive` => `checkAlive`
973 - `_runAsync` => `runAsync`
975 ## [1.1.0] - 2020-05-21
979 - ThreadWorker support async functions as option
980 - Various external library patches
982 ## [1.0.0] - 2020-01-24
986 - FixedThreadPool implementation
987 - DynamicThreadPool implementation
988 - WorkerThread implementation to improve developer experience