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).
12 - Fix task stealing related tasks queue options handling at runtime.
16 - Rename `listTaskFunctions()` to `listTaskFunctionNames()` in pool and worker API.
20 - Add `addTaskFunction()`, `removeTaskFunction()`, `setDefaultTaskFunction()` methods to pool API.
21 - Stricter worker constructor arguments validation.
23 ## [2.6.45] - 2023-09-17
27 - Disable publication on GitHub packages registry on release until authentication issue is fixed.
31 - Add `startWorkers` to pool options to whether start the minimum number of workers at pool creation or not.
32 - Add `start()` method to pool API to start the minimum number of workers.
33 - 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.
34 - Continuous internal benchmarking: https://poolifier.github.io/benchmark-results/dev/bench.
36 ## [2.6.44] - 2023-09-08
40 - Use a dedicated PAT to publish on GitHub packages registry.
44 - Publish on GitHub packages registry on release.
48 - Switch from rome to biome: [PR #1128](https://github.com/poolifier/poolifier/pull/1128).
50 ## [2.6.43] - 2023-09-08
54 - Publish on GitHub packages registry on release.
58 - Switch from rome to biome: [PR #1128](https://github.com/poolifier/poolifier/pull/1128).
60 ## [2.6.42] - 2023-09-06
64 - Optimize hot code paths implementation: avoid unnecessary branching, add and use optimized helpers (min, max), use reduce() array helper, ...
66 ## [2.6.41] - 2023-09-03
70 - Optimize worker choice strategies implementation.
72 ## [2.6.40] - 2023-09-01
76 - Do not pre-choose in WRR worker choice strategy to avoid bias.
77 - Avoid array out of bound in worker choice strategies after worker node removal.
79 ## [2.6.39] - 2023-08-30
83 - Fix race condition in worker choice strategies at worker node info querying while not yet initialized.
85 ## [2.6.38] - 2023-08-30
89 - Bundle typescript types declaration into one file.
93 - Improve interleaved weighted round robin worker choice strategy implementation.
95 ## [2.6.37] - 2023-08-28
99 - Ensure unused worker usage statistics are deleted at runtime.
103 - Rename worker choice strategy options `choiceRetries` to `retries`.
104 - Avoid unnecessary branching in worker choice strategies.
106 ## [2.6.36] - 2023-08-27
110 - Fix pool `execute()` arguments check.
114 - Make continuous tasks stealing algorithm less aggressive.
115 - Fine tune tasks stealing algorithm under back pressure.
117 ## [2.6.35] - 2023-08-25
121 - Don't account worker usage statistics for tasks that have failed.
122 - Fix pool information runtime and wait time median computation.
126 - Update simple moving average implementation to use a circular buffer.
127 - Update simple moving median implementation to use a circular buffer.
128 - Account for stolen tasks in worker usage statistics and pool information.
132 - Continuous tasks stealing algorithm.
134 ## [2.6.34] - 2023-08-24
138 - Avoid cascading tasks stealing under back pressure.
142 - Add fastpath to queued tasks rescheduling.
144 ## [2.6.33] - 2023-08-24
148 - Fix queued tasks rescheduling.
152 - Rename tasks queue options `queueMaxSize` to `size`.
156 - Task stealing scheduling algorithm if tasks queueing is enabled.
158 ## [2.6.32] - 2023-08-23
162 - Ensure no task can be executed when the pool is destroyed.
166 - Add `queueMaxSize` option to tasks queue options.
167 - Add O(1) deque implementation implemented with doubly linked list and use it for tasks queueing.
168 - Add tasks stealing algorithm when a worker node queue is back pressured if tasks queueing is enabled.
170 ## [2.6.31] - 2023-08-20
174 - Fix worker choice strategy retries mechanism in some edge cases.
178 - Make orthogonal worker choice strategies tasks distribution and created dynamic worker usage.
179 - Remove the experimental status of the `LEAST_ELU` worker choice strategy.
181 ## [2.6.30] - 2023-08-19
185 - Ensure pool event `backPressure` is emitted.
186 - Ensure pool event `full` is emitted only once.
187 - Ensure worker node cannot be instantiated without proper arguments.
189 ## [2.6.29] - 2023-08-18
193 - Fix race condition between ready and task functions worker message handling at startup.
194 - Fix duplicate task function worker usage statistics computation per task function.
195 - Update task function worker usage statistics if and only if there's at least two different task functions.
196 - Fix race condition at task function worker usage executing task computation leading to negative value.
200 - 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).
201 - Use back pressure detection in worker choice strategies.
202 - Add worker choice strategies retries mechanism if no worker is eligible.
204 ## [2.6.28] - 2023-08-16
208 - Ensure pool workers are properly initialized.
212 - HTTP server pool examples: express-cluster, express-hybrid.
216 - Remove now useless branching in worker hot code path.
218 ## [2.6.27] - 2023-08-15
222 - Add `KillHandler` type definition to exported types.
226 - Add `destroy` event to pool API.
228 ## [2.6.26] - 2023-08-15
232 - Add kill handler to worker options allowing to execute custom code when worker is killed.
233 - Add `listTaskFunctions()` method to pool API.
234 - SMTP client pool example: nodemailer.
236 ## [2.6.25] - 2023-08-13
240 - HTTP server pool examples: fastify-cluster, fastify-hybrid.
241 - WebSocket server pool examples: ws-cluster, ws-hybrid.
243 ## [2.6.24] - 2023-08-12
247 - Add array of transferable objects to the `execute()` method arguments.
248 - WebSocket server pool examples: ws-worker_threads.
250 ## [2.6.23] - 2023-08-11
254 - 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.
258 - HTTP client pool examples: fetch, node-fetch and axios with multiple task functions.
259 - HTTP server pool examples: express-worker_threads, fastify-worker_threads.
261 ## [2.6.22] - 2023-08-10
265 - Add missing `types` field to package.json `exports`.
269 - Structure markdown documentation (PR #811).
271 ## [2.6.21] - 2023-08-03
275 - Improve code documentation.
276 - Code refactoring and cleanup for better maintainability and readability.
278 ## [2.6.20] - 2023-07-21
282 - Fix queued tasks redistribution on error task execution starvation.
283 - Ensure tasks queueing per worker condition is untangled from the pool busyness semantic.
287 - Drastically reduce lookups by worker in the worker nodes.
289 ## [2.6.19] - 2023-07-20
293 - Dedicated internal communication channel for worker_threads pools.
295 ## [2.6.18] - 2023-07-19
299 - Code refactoring and cleanup for better maintainability and readability. Bundle size is a bit smaller.
301 ## [2.6.17] - 2023-07-16
305 - Add `listTaskFunctions()` method to worker API.
307 ## [2.6.16] - 2023-07-12
311 - Fix pool startup detection.
312 - Fix worker task functions handling.
314 ## [2.6.15] - 2023-07-11
318 - Take into account worker node readiness in worker choice strategies.
320 ## [2.6.14] - 2023-07-10
324 - Fix task function statistics tracking.
326 ## [2.6.13] - 2023-07-10
330 - Add per task function statistics tracking.
331 - Add public methods to manipulate the worker task functions at runtime.
333 ## [2.6.12] - 2023-07-09
337 - Workaround import issue with `node:os` module in node 16.x.x.
339 ## [2.6.11] - 2023-07-09
343 - Fix pool readiness semantic.
345 ## [2.6.10] - 2023-07-08
349 - Ensure workers are not recreated on error at pool startup.
353 - Add `ready` and `strategy` fields to pool information.
354 - Add pool event `ready` to notify when the number of workers created in the pool has reached the maximum size expected and are ready.
355 - Add dynamic pool sizing checks.
357 ## [2.6.9] - 2023-07-07
361 - Recreate the right worker type on uncaught exception.
365 - Add minimum and maximum to internal measurement statistics.
366 - Add `runTime` and `waitTime` to pool information.
367 - Check worker inactive time only on dynamic worker.
369 ## [2.6.8] - 2023-07-03
373 - Brown paper bag release to fix version handling in pool information.
375 ## [2.6.7] - 2023-07-03
379 - Ensure worker queued tasks at error are reassigned to other pool workers.
383 - Add pool `utilization` ratio to pool information.
384 - Add `version` to pool information.
385 - Add worker information to worker nodes.
387 ## [2.6.6] - 2023-07-01
391 - Add safe helper `availableParallelism()` to help sizing the pool.
395 - Ensure message handler is only registered in worker.
397 ## [2.6.5] - 2023-06-27
401 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
405 - Artificial version bump to 2.6.5 to workaround publication issue.
406 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
407 - Ensure pool event is emitted before task error promise rejection.
408 - Fix queued tasks count computation.
412 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
414 ## [2.6.4] - 2023-06-27
418 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
422 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
423 - Ensure pool event is emitted before task error promise rejection.
424 - Fix queued tasks count computation.
428 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
430 ## [2.6.3] - 2023-06-19
434 - Ensure no tasks are queued when trying to soft kill a dynamic worker.
435 - Update strategies internals after statistics computation.
439 - Optimize O(1) queue implementation.
441 ## [2.6.2] - 2023-06-12
445 - Fix new worker use after creation in dynamic pool given the current worker choice strategy.
447 ## [2.6.1] - 2023-06-10
451 - Add worker choice strategy documentation: [README.md](./docs/worker-choice-strategies.md).
455 - Fix average statistics computation: ensure failed tasks are not accounted.
457 ## [2.6.0] - 2023-06-09
461 - Add `LEAST_ELU` worker choice strategy (experimental).
462 - Add tasks ELU instead of runtime support to `FAIR_SHARE` worker choice strategy.
466 - Refactor pool worker node usage internals.
467 - Breaking change: refactor worker choice strategy statistics requirements: the syntax of the worker choice strategy options has changed.
468 - Breaking change: pool information `info` property object fields have been renamed.
472 - Fix wait time accounting.
473 - Ensure worker choice strategy `LEAST_BUSY` accounts also tasks wait time.
474 - Ensure worker choice strategy `LEAST_USED` accounts also queued tasks.
476 ## [2.5.4] - 2023-06-07
480 - Add Event Loop Utilization (ELU) statistics to worker tasks usage.
484 - Compute statistics at the worker level only if needed.
485 - Add `worker_threads` options to thread pool options.
489 - Make the `LEAST_BUSY` strategy only relies on task runtime.
491 ## [2.5.3] - 2023-06-04
495 - Refine pool information content.
496 - Limit pool internals public exposure.
498 ## [2.5.2] - 2023-06-02
502 - Add `taskError` pool event for task execution error.
503 - Add pool information `info` property to pool.
504 - Emit pool information on `busy` and `full` pool events.
506 ## [2.5.1] - 2023-06-01
510 - Add pool option `restartWorkerOnError` to restart worker on uncaught error. Default to `true`.
511 - Add `error` pool event for uncaught worker error.
513 ## [2.5.0] - 2023-05-31
517 - Switch pool event emitter to `EventEmitterAsyncResource`.
518 - Add tasks wait time accounting in per worker tasks usage.
519 - Add interleaved weighted round robin `INTERLEAVED_WEIGHTED_ROUND_ROBIN` worker choice strategy (experimental).
523 - Renamed worker choice strategy `LESS_BUSY` to `LEAST_BUSY` and `LESS_USED` to `LEAST_USED`.
525 ## [2.4.14] - 2023-05-09
529 - Ensure no undefined task runtime can land in the tasks history.
530 - Fix median computation implementation once again.
534 - Unit tests for median and queue implementations.
536 ## [2.4.13] - 2023-05-08
540 - Fix worker choice strategy options validation.
541 - Fix fair share worker choice strategy internals update: ensure virtual task end timestamp is computed at task submission.
543 ## [2.4.12] - 2023-05-06
547 - Support multiple task functions per worker.
548 - Add custom worker weights support to worker choice strategies options.
552 - Use O(1) queue implementation for tasks queueing.
556 - Fix median computation implementation.
557 - Fix fair share worker choice strategy internals update.
559 ## [2.4.11] - 2023-04-23
563 - Optimize free worker finding in worker choice strategies.
565 ## [2.4.10] - 2023-04-15
569 - Fix typescript type definition for task function: ensure the input data is optional.
570 - Fix typescript type definition for pool execute(): ensure the input data is optional.
572 ## [2.4.9] - 2023-04-15
576 - Add tasks queue enablement runtime setter to pool.
577 - Add tasks queue options runtime setter to pool.
578 - Add worker choice strategy options runtime setter to pool.
582 - Remove the tasks queuing experimental status.
586 - Fix task function type definition and validation.
587 - Fix worker choice strategy options handling.
589 ## [2.4.8] - 2023-04-12
593 - Fix message between main worker and worker type definition for tasks.
594 - Fix code documentation.
596 ## [2.4.7] - 2023-04-11
600 - Add worker tasks queue options to pool options.
604 - Fix missing documentation.
606 ## [2.4.6] - 2023-04-10
610 - Ensure one task at a time is executed per worker with tasks queueing enabled.
611 - Properly count worker executing tasks with tasks queueing enabled.
613 ## [2.4.5] - 2023-04-09
617 - Use monotonic high resolution timer for worker tasks runtime.
618 - Add worker tasks median runtime to statistics.
619 - Add worker tasks queue (experimental).
621 ## [2.4.4] - 2023-04-07
625 - Add `PoolEvents` enumeration and `PoolEvent` type.
629 - Destroy worker only on alive check.
631 ## [2.4.3] - 2023-04-07
635 - Fix typedoc generation with inheritance.
637 ## [2.4.2] - 2023-04-06
641 - Add `full` event to dynamic pool.
642 - Keep worker choice strategy in memory for conditional reuse.
646 - Fix possible negative worker key at worker removal in worker choice strategies.
648 ## [2.4.1] - 2023-04-05
652 - Optimize worker choice strategy for dynamic pool.
656 - Ensure dynamic pool does not alter worker choice strategy expected behavior.
658 ## [2.4.0] - 2023-04-04
662 - Add `LESS_BUSY` worker choice strategy.
666 - Optimize worker storage in pool.
667 - Optimize worker alive status check.
668 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
669 - Optimize `LESS_USED` worker choice strategy.
670 - Update benchmark versus external threads pools.
671 - Optimize tasks usage statistics requirements for worker choice strategy.
675 - Ensure trimmable characters are checked at pool initialization.
676 - Fix message id integer overflow.
677 - Fix pool worker removal in worker choice strategy internals.
678 - Fix package publication with pnpm.
680 ## [2.4.0-3] - 2023-04-04
684 - Add `LESS_BUSY` worker choice strategy.
688 - Optimize worker storage in pool.
689 - Optimize worker alive status check.
690 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
691 - Optimize `LESS_USED` worker choice strategy.
692 - Update benchmark versus external threads pools.
696 - Ensure trimmable characters are checked at pool initialization.
697 - Fix message id integer overflow.
698 - Fix pool worker removal in worker choice strategy internals.
699 - Fix package publication with pnpm.
701 ## [2.4.0-2] - 2023-04-03
705 - Add `LESS_BUSY` worker choice strategy.
709 - Optimize worker storage in pool.
710 - Optimize worker alive status check.
711 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
712 - Optimize `LESS_USED` worker choice strategy.
716 - Ensure trimmable characters are checked at pool initialization.
717 - Fix message id integer overflow.
718 - Fix pool worker removal in worker choice strategy internals.
719 - Fix package publication with pnpm.
721 ## [2.4.0-1] - 2023-04-03
725 - Add `LESS_BUSY` worker choice strategy.
729 - Optimize worker storage in pool.
730 - Optimize worker alive status check.
731 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
732 - Optimize `LESS_USED` worker choice strategy.
736 - Ensure trimmable characters are checked at pool initialization.
737 - Fix message id integer overflow.
738 - Fix pool worker removal in worker choice strategy internals.
740 ## [2.4.0-0] - 2023-04-03
744 - Add `LESS_BUSY` worker choice strategy.
748 - Optimize worker storage in pool.
749 - Optimize worker alive status check.
750 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
751 - Optimize `LESS_USED` worker choice strategy.
755 - Ensure trimmable characters are checked at pool initialization.
756 - Fix message id integer overflow.
757 - Fix pool worker removal in worker choice strategy internals.
759 ## [2.3.10] - 2023-03-18
763 - Fix package.json `exports` syntax for ESM and CommonJS.
767 - Permit SemVer pre-release publication.
769 ## [2.3.10-2] - 2023-03-18
773 - Fix package.json `exports` syntax for ESM and CommonJS.
775 ## [2.3.10-1] - 2023-03-18
779 - Permit SemVer pre-release publication.
781 ## [2.3.10-0] - 2023-03-18
785 - Fix package.json `exports` syntax for ESM and CommonJS.
787 ## [2.3.9] - 2023-03-18
791 - Introduce ESM module support along with CommonJS one.
795 - Fix brown paper bag bug referencing the same object literal.
797 ## [2.3.8] - 2023-03-18
801 - Switch internal benchmarking code to benny.
802 - Switch to TypeScript 5.x.x.
803 - Switch rollup bundler plugins to core ones.
804 - Switch to TSDoc syntax.
805 - Enforce conventional commits.
809 - Fix random integer generator.
810 - Fix worker choice strategy pool type identification at initialization.
812 ## [2.3.7] - 2022-10-23
816 - Switch to open collective FOSS project funding platform.
817 - Switch to ts-standard linter configuration on TypeScript code.
821 - Fixed missing async on pool execute method.
822 - Fixed typing in TypeScript example.
823 - Fixed types in unit tests.
825 ## [2.3.6] - 2022-10-22
829 - Cleanup pool attributes and methods.
830 - Refine error types thrown.
834 - Fix continuous integration build on windows.
835 - Fix code coverage reporting by using c8 instead of nyc.
837 ## [2.3.5] - 2022-10-21
841 - Improve benchmarks: add IO intensive task workload, add task size option, integrate code into linter.
842 - Optimize tasks usage lookup implementation.
846 - Fix missed pool event emitter type export.
847 - Fix typedoc documentation generation.
849 ## [2.3.4] - 2022-10-17
853 - Fully automate release process with release-it.
857 - Optimize fair share task scheduling algorithm implementation.
858 - Update benchmark versus external pools results with latest version.
860 ## [2.3.3] - 2022-10-15
864 - Add support for [cluster settings](https://nodejs.org/api/cluster.html#cluster_cluster_settings) in cluster pool options.
866 ## [2.3.2] - 2022-10-14
870 - Optimize fair share worker selection strategy implementation.
874 - Fix WRR worker selection strategy: ensure the condition triggering the round robin can be fulfilled.
876 ## [2.3.1] - 2022-10-13
880 - Pool worker choice strategies:
881 - `WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN` strategy based on weighted round robin scheduling algorithm using tasks execution time for now.
882 - `WorkerChoiceStrategies.FAIR_SHARE` strategy based on fair share scheduling algorithm using tasks execution time for now.
884 ## [2.2.2] - 2022-10-09
888 - Fixed `README.md` file.
890 ## [2.2.1] - 2022-10-08
894 - Dynamic worker choice strategy change at runtime.
896 ## [2.2.0] - 2022-01-05
900 - Support only Node.js version 16.x.x for cluster pool: upstream cluster API have changed on that version.
902 ## [2.1.0] - 2021-08-29
906 - Add an optional pool option `messageHandler` to `PoolOptions<Worker>` for registering a message handler callback on each worker.
910 - `AbstractWorker` class `maxInactiveTime`, `killBehavior` and `async` attributes have been removed in favour of the same ones in the worker options `opts` public attribute.
911 - `AbstractWorker` class `lastTask` attribute have been renamed to `lastTaskTimestamp`.
912 - `AbstractWorker` class `interval` attribute have been renamed to `aliveInterval`.
913 - `AbstractWorker` class cannot be instantiated without specifying the `mainWorker` argument referencing the main worker.
915 ## [2.0.2] - 2021-05-12
919 - Fix `busy` event emission on fixed pool type
921 ## [2.0.1] - 2021-03-16
925 - Check if pool options are properly set.
926 - `busy` event is emitted on all pool types.
928 ## [2.0.0] - 2021-03-01
932 - Now a thread/process by default is not deleted when the task submitted take more time than maxInactiveTime configured (issue #70).
936 - `FullPool` event is now renamed to `busy`.
937 - `maxInactiveTime` on `ThreadWorker` default behavior is now changed, if you want to keep the old behavior set `killBehavior` to `KillBehaviors.HARD`.
938 _Find more details on our JSDoc._
940 - `maxTasks` option on `FixedThreadPool` and `DynamicThreadPool` is now removed since is no more needed.
942 - We changed some internal structures, but you shouldn't be too affected by them as these are internal changes.
944 ### Pool options types declaration merge
946 `FixedThreadPoolOptions` and `DynamicThreadPoolOptions` type declarations have been merged to `PoolOptions<Worker>`.
948 #### New `export` strategy
952 const DynamicThreadPool = require('poolifier/lib/dynamic')
954 const { DynamicThreadPool } = require('poolifier/lib/dynamic')
957 But you should always prefer just using
960 const { DynamicThreadPool } = require('poolifier')
963 #### New type definitions for input data and response
965 For cluster worker and worker-thread pools, you can now only send and receive structured-cloneable data.
966 _This is not a limitation by poolifier but Node.js._
968 #### Public property replacements
970 `numWorkers` property is now `numberOfWorkers`
972 #### Internal (protected) properties and methods renaming
974 These properties are not intended for end users
976 - `id` => `nextMessageId`
978 These methods are not intended for end users
980 - `_chooseWorker` => `chooseWorker`
981 - `_newWorker` => `createWorker`
982 - `_execute` => `internalExecute`
983 - `_chooseWorker` => `chooseWorker`
984 - `_checkAlive` => `checkAlive`
986 - `_runAsync` => `runAsync`
988 ## [1.1.0] - 2020-05-21
992 - ThreadWorker support async functions as option
993 - Various external library patches
995 ## [1.0.0] - 2020-01-24
999 - FixedThreadPool implementation
1000 - DynamicThreadPool implementation
1001 - WorkerThread implementation to improve developer experience