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 - Rename tasks queue options `queueMaxSize` to `size`.
14 ## [2.6.32] - 2023-08-23
18 - Ensure no task can be executed when the pool is destroyed.
22 - Add `queueMaxSize` option to tasks queue options.
23 - Add O(1) deque implementation implemented with doubly linked list and use it for tasks queueing.
24 - Add tasks stealing algorithm when a worker node queue is back pressured if tasks queueing is enabled.
26 ## [2.6.31] - 2023-08-20
30 - Fix worker choice strategy retries mechanism in some edge cases.
34 - Make orthogonal worker choice strategies tasks distribution and created dynamic worker usage.
35 - Remove the experimental status of the `LEAST_ELU` worker choice strategy.
37 ## [2.6.30] - 2023-08-19
41 - Ensure pool event `backPressure` is emitted.
42 - Ensure pool event `full` is emitted only once.
43 - Ensure worker node cannot be instantiated without proper arguments.
45 ## [2.6.29] - 2023-08-18
49 - Fix race condition between ready and task functions worker message handling at startup.
50 - Fix duplicate task function worker usage statistics computation per task function.
51 - Update task function worker usage statistics if and only if there's at least two different task functions.
52 - Fix race condition at task function worker usage executing task computation leading to negative value.
56 - 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).
57 - Use back pressure detection in worker choice strategies.
58 - Add worker choice strategies retries mechanism if no worker is eligible.
60 ## [2.6.28] - 2023-08-16
64 - Ensure pool workers are properly initialized.
68 - HTTP server pool examples: express-cluster, express-hybrid.
72 - Remove now useless branching in worker hot code path.
74 ## [2.6.27] - 2023-08-15
78 - Add `KillHandler` type definition to exported types.
82 - Add `destroy` event to pool API.
84 ## [2.6.26] - 2023-08-15
88 - Add kill handler to worker options allowing to execute custom code when worker is killed.
89 - Add `listTaskFunctions()` method to pool API.
90 - SMTP server pool example: nodemailer.
92 ## [2.6.25] - 2023-08-13
96 - HTTP server pool examples: fastify-cluster, fastify-hybrid.
97 - WebSocket server pool examples: ws-cluster, ws-hybrid.
99 ## [2.6.24] - 2023-08-12
103 - Add array of transferable objects to the `execute()` method arguments.
104 - WebSocket server pool examples: ws-worker_threads.
106 ## [2.6.23] - 2023-08-11
110 - 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.
114 - HTTP client pool examples: fetch, node-fetch and axios with multiple task functions.
115 - HTTP server pool examples: express-worker_threads, fastify-worker_threads.
117 ## [2.6.22] - 2023-08-10
121 - Add missing `types` field to package.json `exports`.
125 - Structure markdown documentation (PR #811).
127 ## [2.6.21] - 2023-08-03
131 - Improve code documentation.
132 - Code refactoring and cleanup for better maintainability and readability.
134 ## [2.6.20] - 2023-07-21
138 - Fix queued tasks redistribution on error task execution starvation.
139 - Ensure tasks queueing per worker condition is untangled from the pool busyness semantic.
143 - Drastically reduce lookups by worker in the worker nodes.
145 ## [2.6.19] - 2023-07-20
149 - Dedicated internal communication channel for worker_threads pools.
151 ## [2.6.18] - 2023-07-19
155 - Code refactoring and cleanup for better maintainability and readability. Bundle size is a bit smaller.
157 ## [2.6.17] - 2023-07-16
161 - Add `listTaskFunctions()` method to worker API.
163 ## [2.6.16] - 2023-07-12
167 - Fix pool startup detection.
168 - Fix worker task functions handling.
170 ## [2.6.15] - 2023-07-11
174 - Take into account worker node readiness in worker choice strategies.
176 ## [2.6.14] - 2023-07-10
180 - Fix task function statistics tracking.
182 ## [2.6.13] - 2023-07-10
186 - Add per task function statistics tracking.
187 - Add public methods to manipulate the worker task functions at runtime.
189 ## [2.6.12] - 2023-07-09
193 - Workaround import issue with `node:os` module in node 16.x.x.
195 ## [2.6.11] - 2023-07-09
199 - Fix pool readiness semantic.
201 ## [2.6.10] - 2023-07-08
205 - Ensure workers are not recreated on error at pool startup.
209 - Add `ready` and `strategy` fields to pool information.
210 - Add pool event `ready` to notify when the number of workers created in the pool has reached the maximum size expected and are ready.
211 - Add dynamic pool sizing checks.
213 ## [2.6.9] - 2023-07-07
217 - Recreate the right worker type on uncaught exception.
221 - Add minimum and maximum to internal measurement statistics.
222 - Add `runTime` and `waitTime` to pool information.
223 - Check worker inactive time only on dynamic worker.
225 ## [2.6.8] - 2023-07-03
229 - Brown paper bag release to fix version handling in pool information.
231 ## [2.6.7] - 2023-07-03
235 - Ensure worker queued tasks at error are reassigned to other pool workers.
239 - Add pool `utilization` ratio to pool information.
240 - Add `version` to pool information.
241 - Add worker information to worker nodes.
243 ## [2.6.6] - 2023-07-01
247 - Add safe helper `availableParallelism()` to help sizing the pool.
251 - Ensure message handler is only registered in worker.
253 ## [2.6.5] - 2023-06-27
257 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
261 - Artificial version bump to 2.6.5 to workaround publication issue.
262 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
263 - Ensure pool event is emitted before task error promise rejection.
264 - Fix queued tasks count computation.
268 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
270 ## [2.6.4] - 2023-06-27
274 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
278 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
279 - Ensure pool event is emitted before task error promise rejection.
280 - Fix queued tasks count computation.
284 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
286 ## [2.6.3] - 2023-06-19
290 - Ensure no tasks are queued when trying to soft kill a dynamic worker.
291 - Update strategies internals after statistics computation.
295 - Optimize O(1) queue implementation.
297 ## [2.6.2] - 2023-06-12
301 - Fix new worker use after creation in dynamic pool given the current worker choice strategy.
303 ## [2.6.1] - 2023-06-10
307 - Add worker choice strategy documentation: [README.md](./docs/worker-choice-strategies.md).
311 - Fix average statistics computation: ensure failed tasks are not accounted.
313 ## [2.6.0] - 2023-06-09
317 - Add `LEAST_ELU` worker choice strategy (experimental).
318 - Add tasks ELU instead of runtime support to `FAIR_SHARE` worker choice strategy.
322 - Refactor pool worker node usage internals.
323 - Breaking change: refactor worker choice strategy statistics requirements: the syntax of the worker choice strategy options has changed.
324 - Breaking change: pool information `info` property object fields have been renamed.
328 - Fix wait time accounting.
329 - Ensure worker choice strategy `LEAST_BUSY` accounts also tasks wait time.
330 - Ensure worker choice strategy `LEAST_USED` accounts also queued tasks.
332 ## [2.5.4] - 2023-06-07
336 - Add Event Loop Utilization (ELU) statistics to worker tasks usage.
340 - Compute statistics at the worker level only if needed.
341 - Add `worker_threads` options to thread pool options.
345 - Make the `LEAST_BUSY` strategy only relies on task runtime.
347 ## [2.5.3] - 2023-06-04
351 - Refine pool information content.
352 - Limit pool internals public exposure.
354 ## [2.5.2] - 2023-06-02
358 - Add `taskError` pool event for task execution error.
359 - Add pool information `info` property to pool.
360 - Emit pool information on `busy` and `full` pool events.
362 ## [2.5.1] - 2023-06-01
366 - Add pool option `restartWorkerOnError` to restart worker on uncaught error. Default to `true`.
367 - Add `error` pool event for uncaught worker error.
369 ## [2.5.0] - 2023-05-31
373 - Switch pool event emitter to `EventEmitterAsyncResource`.
374 - Add tasks wait time accounting in per worker tasks usage.
375 - Add interleaved weighted round robin `INTERLEAVED_WEIGHTED_ROUND_ROBIN` worker choice strategy (experimental).
379 - Renamed worker choice strategy `LESS_BUSY` to `LEAST_BUSY` and `LESS_USED` to `LEAST_USED`.
381 ## [2.4.14] - 2023-05-09
385 - Ensure no undefined task runtime can land in the tasks history.
386 - Fix median computation implementation once again.
390 - Unit tests for median and queue implementations.
392 ## [2.4.13] - 2023-05-08
396 - Fix worker choice strategy options validation.
397 - Fix fair share worker choice strategy internals update: ensure virtual task end timestamp is computed at task submission.
399 ## [2.4.12] - 2023-05-06
403 - Support multiple task functions per worker.
404 - Add custom worker weights support to worker choice strategies options.
408 - Use O(1) queue implementation for tasks queueing.
412 - Fix median computation implementation.
413 - Fix fair share worker choice strategy internals update.
415 ## [2.4.11] - 2023-04-23
419 - Optimize free worker finding in worker choice strategies.
421 ## [2.4.10] - 2023-04-15
425 - Fix typescript type definition for task function: ensure the input data is optional.
426 - Fix typescript type definition for pool execute(): ensure the input data is optional.
428 ## [2.4.9] - 2023-04-15
432 - Add tasks queue enablement runtime setter to pool.
433 - Add tasks queue options runtime setter to pool.
434 - Add worker choice strategy options runtime setter to pool.
438 - Remove the tasks queuing experimental status.
442 - Fix task function type definition and validation.
443 - Fix worker choice strategy options handling.
445 ## [2.4.8] - 2023-04-12
449 - Fix message between main worker and worker type definition for tasks.
450 - Fix code documentation.
452 ## [2.4.7] - 2023-04-11
456 - Add worker tasks queue options to pool options.
460 - Fix missing documentation.
462 ## [2.4.6] - 2023-04-10
466 - Ensure one task at a time is executed per worker with tasks queueing enabled.
467 - Properly count worker executing tasks with tasks queueing enabled.
469 ## [2.4.5] - 2023-04-09
473 - Use monotonic high resolution timer for worker tasks runtime.
474 - Add worker tasks median runtime to statistics.
475 - Add worker tasks queue (experimental).
477 ## [2.4.4] - 2023-04-07
481 - Add `PoolEvents` enumeration and `PoolEvent` type.
485 - Destroy worker only on alive check.
487 ## [2.4.3] - 2023-04-07
491 - Fix typedoc generation with inheritance.
493 ## [2.4.2] - 2023-04-06
497 - Add `full` event to dynamic pool.
498 - Keep worker choice strategy in memory for conditional reuse.
502 - Fix possible negative worker key at worker removal in worker choice strategies.
504 ## [2.4.1] - 2023-04-05
508 - Optimize worker choice strategy for dynamic pool.
512 - Ensure dynamic pool does not alter worker choice strategy expected behavior.
514 ## [2.4.0] - 2023-04-04
518 - Add `LESS_BUSY` worker choice strategy.
522 - Optimize worker storage in pool.
523 - Optimize worker alive status check.
524 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
525 - Optimize `LESS_USED` worker choice strategy.
526 - Update benchmarks versus external threads pools.
527 - Optimize tasks usage statistics requirements for worker choice strategy.
531 - Ensure trimmable characters are checked at pool initialization.
532 - Fix message id integer overflow.
533 - Fix pool worker removal in worker choice strategy internals.
534 - Fix package publication with pnpm.
536 ## [2.4.0-3] - 2023-04-04
540 - Add `LESS_BUSY` worker choice strategy.
544 - Optimize worker storage in pool.
545 - Optimize worker alive status check.
546 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
547 - Optimize `LESS_USED` worker choice strategy.
548 - Update benchmarks versus external threads pools.
552 - Ensure trimmable characters are checked at pool initialization.
553 - Fix message id integer overflow.
554 - Fix pool worker removal in worker choice strategy internals.
555 - Fix package publication with pnpm.
557 ## [2.4.0-2] - 2023-04-03
561 - Add `LESS_BUSY` worker choice strategy.
565 - Optimize worker storage in pool.
566 - Optimize worker alive status check.
567 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
568 - Optimize `LESS_USED` worker choice strategy.
572 - Ensure trimmable characters are checked at pool initialization.
573 - Fix message id integer overflow.
574 - Fix pool worker removal in worker choice strategy internals.
575 - Fix package publication with pnpm.
577 ## [2.4.0-1] - 2023-04-03
581 - Add `LESS_BUSY` worker choice strategy.
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.
592 - Ensure trimmable characters are checked at pool initialization.
593 - Fix message id integer overflow.
594 - Fix pool worker removal in worker choice strategy internals.
596 ## [2.4.0-0] - 2023-04-03
600 - Add `LESS_BUSY` worker choice strategy.
604 - Optimize worker storage in pool.
605 - Optimize worker alive status check.
606 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
607 - Optimize `LESS_USED` worker choice strategy.
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.
615 ## [2.3.10] - 2023-03-18
619 - Fix package.json `exports` syntax for ESM and CommonJS.
623 - Permit SemVer pre-release publication.
625 ## [2.3.10-2] - 2023-03-18
629 - Fix package.json `exports` syntax for ESM and CommonJS.
631 ## [2.3.10-1] - 2023-03-18
635 - Permit SemVer pre-release publication.
637 ## [2.3.10-0] - 2023-03-18
641 - Fix package.json `exports` syntax for ESM and CommonJS.
643 ## [2.3.9] - 2023-03-18
647 - Introduce ESM module support along with CommonJS one.
651 - Fix brown paper bag bug referencing the same object literal.
653 ## [2.3.8] - 2023-03-18
657 - Switch internal benchmarking code to benny.
658 - Switch to TypeScript 5.x.x.
659 - Switch rollup bundler plugins to core ones.
660 - Switch to TSDoc syntax.
661 - Enforce conventional commits.
665 - Fix random integer generator.
666 - Fix worker choice strategy pool type identification at initialization.
668 ## [2.3.7] - 2022-10-23
672 - Switch to open collective FOSS project funding platform.
673 - Switch to ts-standard linter configuration on TypeScript code.
677 - Fixed missing async on pool execute method.
678 - Fixed typing in TypeScript example.
679 - Fixed types in unit tests.
681 ## [2.3.6] - 2022-10-22
685 - Cleanup pool attributes and methods.
686 - Refine error types thrown.
690 - Fix continuous integration build on windows.
691 - Fix code coverage reporting by using c8 instead of nyc.
693 ## [2.3.5] - 2022-10-21
697 - Improve benchmarks: add IO intensive task workload, add task size option, integrate code into linter.
698 - Optimize tasks usage lookup implementation.
702 - Fix missed pool event emitter type export.
703 - Fix typedoc documentation generation.
705 ## [2.3.4] - 2022-10-17
709 - Fully automate release process with release-it.
713 - Optimize fair share task scheduling algorithm implementation.
714 - Update benchmarks versus external pools results with latest version.
716 ## [2.3.3] - 2022-10-15
720 - Add support for [cluster settings](https://nodejs.org/api/cluster.html#cluster_cluster_settings) in cluster pool options.
722 ## [2.3.2] - 2022-10-14
726 - Optimize fair share worker selection strategy implementation.
730 - Fix WRR worker selection strategy: ensure the condition triggering the round robin can be fulfilled.
732 ## [2.3.1] - 2022-10-13
736 - Pool worker choice strategies:
737 - `WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN` strategy based on weighted round robin scheduling algorithm using tasks execution time for now.
738 - `WorkerChoiceStrategies.FAIR_SHARE` strategy based on fair share scheduling algorithm using tasks execution time for now.
740 ## [2.2.2] - 2022-10-09
744 - Fixed `README.md` file.
746 ## [2.2.1] - 2022-10-08
750 - Dynamic worker choice strategy change at runtime.
752 ## [2.2.0] - 2022-01-05
756 - Support only Node.js version 16.x.x for cluster pool: upstream cluster API have changed on that version.
758 ## [2.1.0] - 2021-08-29
762 - Add an optional pool option `messageHandler` to `PoolOptions<Worker>` for registering a message handler callback on each worker.
766 - `AbstractWorker` class `maxInactiveTime`, `killBehavior` and `async` attributes have been removed in favour of the same ones in the worker options `opts` public attribute.
767 - `AbstractWorker` class `lastTask` attribute have been renamed to `lastTaskTimestamp`.
768 - `AbstractWorker` class `interval` attribute have been renamed to `aliveInterval`.
769 - `AbstractWorker` class cannot be instantiated without specifying the `mainWorker` argument referencing the main worker.
771 ## [2.0.2] - 2021-05-12
775 - Fix `busy` event emission on fixed pool type
777 ## [2.0.1] - 2021-03-16
781 - Check if pool options are properly set.
782 - `busy` event is emitted on all pool types.
784 ## [2.0.0] - 2021-03-01
788 - Now a thread/process by default is not deleted when the task submitted take more time than maxInactiveTime configured (issue #70).
792 - `FullPool` event is now renamed to `busy`.
793 - `maxInactiveTime` on `ThreadWorker` default behavior is now changed, if you want to keep the old behavior set `killBehavior` to `KillBehaviors.HARD`.
794 _Find more details on our JSDoc._
796 - `maxTasks` option on `FixedThreadPool` and `DynamicThreadPool` is now removed since is no more needed.
798 - We changed some internal structures, but you shouldn't be too affected by them as these are internal changes.
800 ### Pool options types declaration merge
802 `FixedThreadPoolOptions` and `DynamicThreadPoolOptions` type declarations have been merged to `PoolOptions<Worker>`.
804 #### New `export` strategy
808 const DynamicThreadPool = require('poolifier/lib/dynamic')
810 const { DynamicThreadPool } = require('poolifier/lib/dynamic')
813 But you should always prefer just using
816 const { DynamicThreadPool } = require('poolifier')
819 #### New type definitions for input data and response
821 For cluster worker and worker-thread pools, you can now only send and receive structured-cloneable data.
822 _This is not a limitation by poolifier but Node.js._
824 #### Public property replacements
826 `numWorkers` property is now `numberOfWorkers`
828 #### Internal (protected) properties and methods renaming
830 These properties are not intended for end users
832 - `id` => `nextMessageId`
834 These methods are not intended for end users
836 - `_chooseWorker` => `chooseWorker`
837 - `_newWorker` => `createWorker`
838 - `_execute` => `internalExecute`
839 - `_chooseWorker` => `chooseWorker`
840 - `_checkAlive` => `checkAlive`
842 - `_runAsync` => `runAsync`
844 ## [1.1.0] - 2020-05-21
848 - ThreadWorker support async functions as option
849 - Various external library patches
851 ## [1.0.0] - 2020-01-24
855 - FixedThreadPool implementation
856 - DynamicThreadPool implementation
857 - WorkerThread implementation to improve developer experience