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 - Ensure pool event `backPressure` is emitted.
13 - Ensure pool event `full` is emitted only once.
15 ## [2.6.29] - 2023-08-18
19 - Fix race condition between ready and task functions worker message handling at startup.
20 - Fix duplicate task function worker usage statistics computation per task function.
21 - Update task function worker usage statistics if and only if there's at least two different task functions.
22 - Fix race condition at task function worker usage executing task computation leading to negative value.
26 - 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).
27 - Use back pressure detection in worker choice strategies.
28 - Add worker choice strategies retries mechanism if no worker is eligible.
30 ## [2.6.28] - 2023-08-16
34 - Ensure pool workers are properly initialized.
38 - HTTP server pool examples: express-cluster, express-hybrid.
42 - Remove now useless branching in worker hot code path.
44 ## [2.6.27] - 2023-08-15
48 - Add `KillHandler` type definition to exported types.
52 - Add `destroy` event to pool API.
54 ## [2.6.26] - 2023-08-15
58 - Add kill handler to worker options allowing to execute custom code when worker is killed.
59 - Add `listTaskFunctions()` method to pool API.
60 - SMTP server pool example: nodemailer.
62 ## [2.6.25] - 2023-08-13
66 - HTTP server pool examples: fastify-cluster, fastify-hybrid.
67 - WebSocket server pool examples: ws-cluster, ws-hybrid.
69 ## [2.6.24] - 2023-08-12
73 - Add array of transferable objects to the `execute()` method arguments.
74 - WebSocket server pool examples: ws-worker_threads.
76 ## [2.6.23] - 2023-08-11
80 - 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.
84 - HTTP client pool examples: fetch, node-fetch and axios with multiple task functions.
85 - HTTP server pool examples: express-worker_threads, fastify-worker_threads.
87 ## [2.6.22] - 2023-08-10
91 - Add missing `types` field to package.json `exports`.
95 - Structure markdown documentation (PR #811).
97 ## [2.6.21] - 2023-08-03
101 - Improve code documentation.
102 - Code refactoring and cleanup for better maintainability and readability.
104 ## [2.6.20] - 2023-07-21
108 - Fix queued tasks redistribution on error task execution starvation.
109 - Ensure tasks queueing per worker condition is untangled from the pool busyness semantic.
113 - Drastically reduce lookups by worker in the worker nodes.
115 ## [2.6.19] - 2023-07-20
119 - Dedicated internal communication channel for worker_threads pools.
121 ## [2.6.18] - 2023-07-19
125 - Code refactoring and cleanup for better maintainability and readability. Bundle size is a bit smaller.
127 ## [2.6.17] - 2023-07-16
131 - Add `listTaskFunctions()` method to worker API.
133 ## [2.6.16] - 2023-07-12
137 - Fix pool startup detection.
138 - Fix worker task functions handling.
140 ## [2.6.15] - 2023-07-11
144 - Take into account worker node readiness in worker choice strategies.
146 ## [2.6.14] - 2023-07-10
150 - Fix task function statistics tracking.
152 ## [2.6.13] - 2023-07-10
156 - Add per task function statistics tracking.
157 - Add public methods to manipulate the worker task functions at runtime.
159 ## [2.6.12] - 2023-07-09
163 - Workaround import issue with `node:os` module in node 16.x.x.
165 ## [2.6.11] - 2023-07-09
169 - Fix pool readiness semantic.
171 ## [2.6.10] - 2023-07-08
175 - Ensure workers are not recreated on error at pool startup.
179 - Add `ready` and `strategy` fields to pool information.
180 - Add pool event `ready` to notify when the number of workers created in the pool has reached the maximum size expected and are ready.
181 - Add dynamic pool sizing checks.
183 ## [2.6.9] - 2023-07-07
187 - Recreate the right worker type on uncaught exception.
191 - Add minimum and maximum to internal measurement statistics.
192 - Add `runTime` and `waitTime` to pool information.
193 - Check worker inactive time only on dynamic worker.
195 ## [2.6.8] - 2023-07-03
199 - Brown paper bag release to fix version handling in pool information.
201 ## [2.6.7] - 2023-07-03
205 - Ensure worker queued tasks at error are reassigned to other pool workers.
209 - Add pool `utilization` ratio to pool information.
210 - Add `version` to pool information.
211 - Add worker information to worker nodes.
213 ## [2.6.6] - 2023-07-01
217 - Add safe helper `availableParallelism()` to help sizing the pool.
221 - Ensure message handler is only registered in worker.
223 ## [2.6.5] - 2023-06-27
227 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
231 - Artificial version bump to 2.6.5 to workaround publication issue.
232 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
233 - Ensure pool event is emitted before task error promise rejection.
234 - Fix queued tasks count computation.
238 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
240 ## [2.6.4] - 2023-06-27
244 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
248 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
249 - Ensure pool event is emitted before task error promise rejection.
250 - Fix queued tasks count computation.
254 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
256 ## [2.6.3] - 2023-06-19
260 - Ensure no tasks are queued when trying to soft kill a dynamic worker.
261 - Update strategies internals after statistics computation.
265 - Optimize O(1) queue implementation.
267 ## [2.6.2] - 2023-06-12
271 - Fix new worker use after creation in dynamic pool given the current worker choice strategy.
273 ## [2.6.1] - 2023-06-10
277 - Add worker choice strategy documentation: [README.md](./docs/worker-choice-strategies.md).
281 - Fix average statistics computation: ensure failed tasks are not accounted.
283 ## [2.6.0] - 2023-06-09
287 - Add `LEAST_ELU` worker choice strategy (experimental).
288 - Add tasks ELU instead of runtime support to `FAIR_SHARE` worker choice strategy.
292 - Refactor pool worker node usage internals.
293 - Breaking change: refactor worker choice strategy statistics requirements: the syntax of the worker choice strategy options has changed.
294 - Breaking change: pool information `info` property object fields have been renamed.
298 - Fix wait time accounting.
299 - Ensure worker choice strategy `LEAST_BUSY` accounts also tasks wait time.
300 - Ensure worker choice strategy `LEAST_USED` accounts also queued tasks.
302 ## [2.5.4] - 2023-06-07
306 - Add Event Loop Utilization (ELU) statistics to worker tasks usage.
310 - Compute statistics at the worker level only if needed.
311 - Add `worker_threads` options to thread pool options.
315 - Make the `LEAST_BUSY` strategy only relies on task runtime.
317 ## [2.5.3] - 2023-06-04
321 - Refine pool information content.
322 - Limit pool internals public exposure.
324 ## [2.5.2] - 2023-06-02
328 - Add `taskError` pool event for task execution error.
329 - Add pool information `info` property to pool.
330 - Emit pool information on `busy` and `full` pool events.
332 ## [2.5.1] - 2023-06-01
336 - Add pool option `restartWorkerOnError` to restart worker on uncaught error. Default to `true`.
337 - Add `error` pool event for uncaught worker error.
339 ## [2.5.0] - 2023-05-31
343 - Switch pool event emitter to `EventEmitterAsyncResource`.
344 - Add tasks wait time accounting in per worker tasks usage.
345 - Add interleaved weighted round robin `INTERLEAVED_WEIGHTED_ROUND_ROBIN` worker choice strategy (experimental).
349 - Renamed worker choice strategy `LESS_BUSY` to `LEAST_BUSY` and `LESS_USED` to `LEAST_USED`.
351 ## [2.4.14] - 2023-05-09
355 - Ensure no undefined task runtime can land in the tasks history.
356 - Fix median computation implementation once again.
360 - Unit tests for median and queue implementations.
362 ## [2.4.13] - 2023-05-08
366 - Fix worker choice strategy options validation.
367 - Fix fair share worker choice strategy internals update: ensure virtual task end timestamp is computed at task submission.
369 ## [2.4.12] - 2023-05-06
373 - Support multiple task functions per worker.
374 - Add custom worker weights support to worker choice strategies options.
378 - Use O(1) queue implementation for tasks queueing.
382 - Fix median computation implementation.
383 - Fix fair share worker choice strategy internals update.
385 ## [2.4.11] - 2023-04-23
389 - Optimize free worker finding in worker choice strategies.
391 ## [2.4.10] - 2023-04-15
395 - Fix typescript type definition for task function: ensure the input data is optional.
396 - Fix typescript type definition for pool execute(): ensure the input data is optional.
398 ## [2.4.9] - 2023-04-15
402 - Add tasks queue enablement runtime setter to pool.
403 - Add tasks queue options runtime setter to pool.
404 - Add worker choice strategy options runtime setter to pool.
408 - Remove the tasks queuing experimental status.
412 - Fix task function type definition and validation.
413 - Fix worker choice strategy options handling.
415 ## [2.4.8] - 2023-04-12
419 - Fix message between main worker and worker type definition for tasks.
420 - Fix code documentation.
422 ## [2.4.7] - 2023-04-11
426 - Add worker tasks queue options to pool options.
430 - Fix missing documentation.
432 ## [2.4.6] - 2023-04-10
436 - Ensure one task at a time is executed per worker with tasks queueing enabled.
437 - Properly count worker executing tasks with tasks queueing enabled.
439 ## [2.4.5] - 2023-04-09
443 - Use monotonic high resolution timer for worker tasks runtime.
444 - Add worker tasks median runtime to statistics.
445 - Add worker tasks queue (experimental).
447 ## [2.4.4] - 2023-04-07
451 - Add `PoolEvents` enumeration and `PoolEvent` type.
455 - Destroy worker only on alive check.
457 ## [2.4.3] - 2023-04-07
461 - Fix typedoc generation with inheritance.
463 ## [2.4.2] - 2023-04-06
467 - Add `full` event to dynamic pool.
468 - Keep worker choice strategy in memory for conditional reuse.
472 - Fix possible negative worker key at worker removal in worker choice strategies.
474 ## [2.4.1] - 2023-04-05
478 - Optimize worker choice strategy for dynamic pool.
482 - Ensure dynamic pool does not alter worker choice strategy expected behavior.
484 ## [2.4.0] - 2023-04-04
488 - Add `LESS_BUSY` worker choice strategy.
492 - Optimize worker storage in pool.
493 - Optimize worker alive status check.
494 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
495 - Optimize `LESS_USED` worker choice strategy.
496 - Update benchmarks versus external threads pools.
497 - Optimize tasks usage statistics requirements for worker choice strategy.
501 - Ensure trimmable characters are checked at pool initialization.
502 - Fix message id integer overflow.
503 - Fix pool worker removal in worker choice strategy internals.
504 - Fix package publication with pnpm.
506 ## [2.4.0-3] - 2023-04-04
510 - Add `LESS_BUSY` worker choice strategy.
514 - Optimize worker storage in pool.
515 - Optimize worker alive status check.
516 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
517 - Optimize `LESS_USED` worker choice strategy.
518 - Update benchmarks versus external threads pools.
522 - Ensure trimmable characters are checked at pool initialization.
523 - Fix message id integer overflow.
524 - Fix pool worker removal in worker choice strategy internals.
525 - Fix package publication with pnpm.
527 ## [2.4.0-2] - 2023-04-03
531 - Add `LESS_BUSY` worker choice strategy.
535 - Optimize worker storage in pool.
536 - Optimize worker alive status check.
537 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
538 - Optimize `LESS_USED` worker choice strategy.
542 - Ensure trimmable characters are checked at pool initialization.
543 - Fix message id integer overflow.
544 - Fix pool worker removal in worker choice strategy internals.
545 - Fix package publication with pnpm.
547 ## [2.4.0-1] - 2023-04-03
551 - Add `LESS_BUSY` worker choice strategy.
555 - Optimize worker storage in pool.
556 - Optimize worker alive status check.
557 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
558 - Optimize `LESS_USED` worker choice strategy.
562 - Ensure trimmable characters are checked at pool initialization.
563 - Fix message id integer overflow.
564 - Fix pool worker removal in worker choice strategy internals.
566 ## [2.4.0-0] - 2023-04-03
570 - Add `LESS_BUSY` worker choice strategy.
574 - Optimize worker storage in pool.
575 - Optimize worker alive status check.
576 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
577 - Optimize `LESS_USED` worker choice strategy.
581 - Ensure trimmable characters are checked at pool initialization.
582 - Fix message id integer overflow.
583 - Fix pool worker removal in worker choice strategy internals.
585 ## [2.3.10] - 2023-03-18
589 - Fix package.json `exports` syntax for ESM and CommonJS.
593 - Permit SemVer pre-release publication.
595 ## [2.3.10-2] - 2023-03-18
599 - Fix package.json `exports` syntax for ESM and CommonJS.
601 ## [2.3.10-1] - 2023-03-18
605 - Permit SemVer pre-release publication.
607 ## [2.3.10-0] - 2023-03-18
611 - Fix package.json `exports` syntax for ESM and CommonJS.
613 ## [2.3.9] - 2023-03-18
617 - Introduce ESM module support along with CommonJS one.
621 - Fix brown paper bag bug referencing the same object literal.
623 ## [2.3.8] - 2023-03-18
627 - Switch internal benchmarking code to benny.
628 - Switch to TypeScript 5.x.x.
629 - Switch rollup bundler plugins to core ones.
630 - Switch to TSDoc syntax.
631 - Enforce conventional commits.
635 - Fix random integer generator.
636 - Fix worker choice strategy pool type identification at initialization.
638 ## [2.3.7] - 2022-10-23
642 - Switch to open collective FOSS project funding platform.
643 - Switch to ts-standard linter configuration on TypeScript code.
647 - Fixed missing async on pool execute method.
648 - Fixed typing in TypeScript example.
649 - Fixed types in unit tests.
651 ## [2.3.6] - 2022-10-22
655 - Cleanup pool attributes and methods.
656 - Refine error types thrown.
660 - Fix continuous integration build on windows.
661 - Fix code coverage reporting by using c8 instead of nyc.
663 ## [2.3.5] - 2022-10-21
667 - Improve benchmarks: add IO intensive task workload, add task size option, integrate code into linter.
668 - Optimize tasks usage lookup implementation.
672 - Fix missed pool event emitter type export.
673 - Fix typedoc documentation generation.
675 ## [2.3.4] - 2022-10-17
679 - Fully automate release process with release-it.
683 - Optimize fair share task scheduling algorithm implementation.
684 - Update benchmarks versus external pools results with latest version.
686 ## [2.3.3] - 2022-10-15
690 - Add support for [cluster settings](https://nodejs.org/api/cluster.html#cluster_cluster_settings) in cluster pool options.
692 ## [2.3.2] - 2022-10-14
696 - Optimize fair share worker selection strategy implementation.
700 - Fix WRR worker selection strategy: ensure the condition triggering the round robin can be fulfilled.
702 ## [2.3.1] - 2022-10-13
706 - Pool worker choice strategies:
707 - `WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN` strategy based on weighted round robin scheduling algorithm using tasks execution time for now.
708 - `WorkerChoiceStrategies.FAIR_SHARE` strategy based on fair share scheduling algorithm using tasks execution time for now.
710 ## [2.2.2] - 2022-10-09
714 - Fixed `README.md` file.
716 ## [2.2.1] - 2022-10-08
720 - Dynamic worker choice strategy change at runtime.
722 ## [2.2.0] - 2022-01-05
726 - Support only Node.js version 16.x.x for cluster pool: upstream cluster API have changed on that version.
728 ## [2.1.0] - 2021-08-29
732 - Add an optional pool option `messageHandler` to `PoolOptions<Worker>` for registering a message handler callback on each worker.
736 - `AbstractWorker` class `maxInactiveTime`, `killBehavior` and `async` attributes have been removed in favour of the same ones in the worker options `opts` public attribute.
737 - `AbstractWorker` class `lastTask` attribute have been renamed to `lastTaskTimestamp`.
738 - `AbstractWorker` class `interval` attribute have been renamed to `aliveInterval`.
739 - `AbstractWorker` class cannot be instantiated without specifying the `mainWorker` argument referencing the main worker.
741 ## [2.0.2] - 2021-05-12
745 - Fix `busy` event emission on fixed pool type
747 ## [2.0.1] - 2021-03-16
751 - Check if pool options are properly set.
752 - `busy` event is emitted on all pool types.
754 ## [2.0.0] - 2021-03-01
758 - Now a thread/process by default is not deleted when the task submitted take more time than maxInactiveTime configured (issue #70).
762 - `FullPool` event is now renamed to `busy`.
763 - `maxInactiveTime` on `ThreadWorker` default behavior is now changed, if you want to keep the old behavior set `killBehavior` to `KillBehaviors.HARD`.
764 _Find more details on our JSDoc._
766 - `maxTasks` option on `FixedThreadPool` and `DynamicThreadPool` is now removed since is no more needed.
768 - We changed some internal structures, but you shouldn't be too affected by them as these are internal changes.
770 ### Pool options types declaration merge
772 `FixedThreadPoolOptions` and `DynamicThreadPoolOptions` type declarations have been merged to `PoolOptions<Worker>`.
774 #### New `export` strategy
778 const DynamicThreadPool = require('poolifier/lib/dynamic')
780 const { DynamicThreadPool } = require('poolifier/lib/dynamic')
783 But you should always prefer just using
786 const { DynamicThreadPool } = require('poolifier')
789 #### New type definitions for input data and response
791 For cluster worker and worker-thread pools, you can now only send and receive structured-cloneable data.
792 _This is not a limitation by poolifier but Node.js._
794 #### Public property replacements
796 `numWorkers` property is now `numberOfWorkers`
798 #### Internal (protected) properties and methods renaming
800 These properties are not intended for end users
802 - `id` => `nextMessageId`
804 These methods are not intended for end users
806 - `_chooseWorker` => `chooseWorker`
807 - `_newWorker` => `createWorker`
808 - `_execute` => `internalExecute`
809 - `_chooseWorker` => `chooseWorker`
810 - `_checkAlive` => `checkAlive`
812 - `_runAsync` => `runAsync`
814 ## [1.1.0] - 2020-05-21
818 - ThreadWorker support async functions as option
819 - Various external library patches
821 ## [1.0.0] - 2020-01-24
825 - FixedThreadPool implementation
826 - DynamicThreadPool implementation
827 - WorkerThread implementation to improve developer experience