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 race condition between ready and task functions worker message handling at startup.
13 - Fix duplicate task function worker usage statistics computation per task function.
14 - Update task function worker usage statistics if and only if there's at least two different task functions.
15 - Fix race condition at task function worker usage executing task computation leading to negative value.
19 - Add back pressure detection on the worker node queue. Event `backPressure` is emitted all worker node queues are full (worker node queue size >= poolMaxSize^2).
20 - Use back pressure detection in worker choice strategies.
21 - Add worker choice strategies retries mechanism if no worker is eligible.
23 ## [2.6.28] - 2023-08-16
27 - Ensure pool workers are properly initialized.
31 - HTTP server pool examples: express-cluster, express-hybrid.
35 - Remove now useless branching in worker hot code path.
37 ## [2.6.27] - 2023-08-15
41 - Add `KillHandler` type definition to exported types.
45 - Add `destroy` event to pool API.
47 ## [2.6.26] - 2023-08-15
51 - Add kill handler to worker options allowing to execute custom code when worker is killed.
52 - Add `listTaskFunctions()` method to pool API.
53 - SMTP server pool example: nodemailer.
55 ## [2.6.25] - 2023-08-13
59 - HTTP server pool examples: fastify-cluster, fastify-hybrid.
60 - WebSocket server pool examples: ws-cluster, ws-hybrid.
62 ## [2.6.24] - 2023-08-12
66 - Add array of transferable objects to the `execute()` method arguments.
67 - WebSocket server pool examples: ws-worker_threads.
69 ## [2.6.23] - 2023-08-11
73 - 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.
77 - HTTP client pool examples: fetch, node-fetch and axios with multiple task functions.
78 - HTTP server pool examples: express-worker_threads, fastify-worker_threads.
80 ## [2.6.22] - 2023-08-10
84 - Add missing `types` field to package.json `exports`.
88 - Structure markdown documentation (PR #811).
90 ## [2.6.21] - 2023-08-03
94 - Improve code documentation.
95 - Code refactoring and cleanup for better maintainability and readability.
97 ## [2.6.20] - 2023-07-21
101 - Fix queued tasks redistribution on error task execution starvation.
102 - Ensure task queueing per worker condition is untangled from the pool busyness semantic.
106 - Drastically reduce lookups by worker in the worker nodes.
108 ## [2.6.19] - 2023-07-20
112 - Dedicated internal communication channel for worker_threads pools.
114 ## [2.6.18] - 2023-07-19
118 - Code refactoring and cleanup for better maintainability and readability. Bundle size is a bit smaller.
120 ## [2.6.17] - 2023-07-16
124 - Add `listTaskFunctions()` method to worker API.
126 ## [2.6.16] - 2023-07-12
130 - Fix pool startup detection.
131 - Fix worker task functions handling.
133 ## [2.6.15] - 2023-07-11
137 - Take into account worker node readiness in worker choice strategies.
139 ## [2.6.14] - 2023-07-10
143 - Fix task function statistics tracking.
145 ## [2.6.13] - 2023-07-10
149 - Add per task function statistics tracking.
150 - Add public methods to manipulate the worker task functions at runtime.
152 ## [2.6.12] - 2023-07-09
156 - Workaround import issue with `node:os` module in node 16.x.x.
158 ## [2.6.11] - 2023-07-09
162 - Fix pool readiness semantic.
164 ## [2.6.10] - 2023-07-08
168 - Ensure workers are not recreated on error at pool startup.
172 - Add `ready` and `strategy` fields to pool information.
173 - Add pool event `ready` to notify when the number of workers created in the pool has reached the maximum size expected and are ready.
174 - Add dynamic pool sizing checks.
176 ## [2.6.9] - 2023-07-07
180 - Recreate the right worker type on uncaught exception.
184 - Add minimum and maximum to internal measurement statistics.
185 - Add `runTime` and `waitTime` to pool information.
186 - Check worker inactive time only on dynamic worker.
188 ## [2.6.8] - 2023-07-03
192 - Brown paper bag release to fix version handling in pool information.
194 ## [2.6.7] - 2023-07-03
198 - Ensure worker queued tasks at error are reassigned to other pool workers.
202 - Add pool `utilization` ratio to pool information.
203 - Add `version` to pool information.
204 - Add worker information to worker nodes.
206 ## [2.6.6] - 2023-07-01
210 - Add safe helper `availableParallelism` to help sizing the pool.
214 - Ensure message handler is only registered in worker.
216 ## [2.6.5] - 2023-06-27
220 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
224 - Artificial version bump to 2.6.5 to workaround publication issue.
225 - Ensure cluster pool destroy() gracefully shutdowns worker's server.
226 - Ensure pool event is emitted before task error promise rejection.
227 - Fix queued tasks count computation.
231 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
233 ## [2.6.4] - 2023-06-27
237 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
241 - Ensure cluster pool destroy() gracefully shutdowns worker's server.
242 - Ensure pool event is emitted before task error promise rejection.
243 - Fix queued tasks count computation.
247 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
249 ## [2.6.3] - 2023-06-19
253 - Ensure no tasks are queued when trying to soft kill a dynamic worker.
254 - Update strategies internals after statistics computation.
258 - Optimize O(1) queue implementation.
260 ## [2.6.2] - 2023-06-12
264 - Fix new worker use after creation in dynamic pool given the current worker choice strategy.
266 ## [2.6.1] - 2023-06-10
270 - Add worker choice strategy documentation: [README.md](./docs/worker-choice-strategies.md).
274 - Fix average statistics computation: ensure failed tasks are not accounted.
276 ## [2.6.0] - 2023-06-09
280 - Add `LEAST_ELU` worker choice strategy (experimental).
281 - Add tasks ELU instead of runtime support to `FAIR_SHARE` worker choice strategy.
285 - Refactor pool worker node usage internals.
286 - Breaking change: refactor worker choice strategy statistics requirements: the syntax of the worker choice strategy options has changed.
287 - Breaking change: pool information `info` property object fields have been renamed.
291 - Fix wait time accounting.
292 - Ensure worker choice strategy `LEAST_BUSY` accounts also tasks wait time.
293 - Ensure worker choice strategy `LEAST_USED` accounts also queued tasks.
295 ## [2.5.4] - 2023-06-07
299 - Add Event Loop Utilization (ELU) statistics to worker tasks usage.
303 - Compute statistics at the worker level only if needed.
304 - Add `worker_threads` options to thread pool options.
308 - Make the `LEAST_BUSY` strategy only relies on task runtime.
310 ## [2.5.3] - 2023-06-04
314 - Refine pool information content.
315 - Limit pool internals public exposure.
317 ## [2.5.2] - 2023-06-02
321 - Add `taskError` pool event for task execution error.
322 - Add pool information `info` property to pool.
323 - Emit pool information on `busy` and `full` pool events.
325 ## [2.5.1] - 2023-06-01
329 - Add pool option `restartWorkerOnError` to restart worker on uncaught error. Default to `true`.
330 - Add `error` pool event for uncaught worker error.
332 ## [2.5.0] - 2023-05-31
336 - Switch pool event emitter to `EventEmitterAsyncResource`.
337 - Add tasks wait time accounting in per worker tasks usage.
338 - Add interleaved weighted round robin `INTERLEAVED_WEIGHTED_ROUND_ROBIN` worker choice strategy (experimental).
342 - Renamed worker choice strategy `LESS_BUSY` to `LEAST_BUSY` and `LESS_USED` to `LEAST_USED`.
344 ## [2.4.14] - 2023-05-09
348 - Ensure no undefined task runtime can land in the tasks history.
349 - Fix median computation implementation once again.
353 - Unit tests for median and queue implementations.
355 ## [2.4.13] - 2023-05-08
359 - Fix worker choice strategy options validation.
360 - Fix fair share worker choice strategy internals update: ensure virtual task end timestamp is computed at task submission.
362 ## [2.4.12] - 2023-05-06
366 - Support multiple task functions per worker.
367 - Add custom worker weights support to worker choice strategies options.
371 - Use O(1) queue implementation for tasks queueing.
375 - Fix median computation implementation.
376 - Fix fair share worker choice strategy internals update.
378 ## [2.4.11] - 2023-04-23
382 - Optimize free worker finding in worker choice strategies.
384 ## [2.4.10] - 2023-04-15
388 - Fix typescript type definition for task function: ensure the input data is optional.
389 - Fix typescript type definition for pool execute(): ensure the input data is optional.
391 ## [2.4.9] - 2023-04-15
395 - Add tasks queue enablement runtime setter to pool.
396 - Add tasks queue options runtime setter to pool.
397 - Add worker choice strategy options runtime setter to pool.
401 - Remove the tasks queuing experimental status.
405 - Fix task function type definition and validation.
406 - Fix worker choice strategy options handling.
408 ## [2.4.8] - 2023-04-12
412 - Fix message between main worker and worker type definition for tasks.
413 - Fix code documentation.
415 ## [2.4.7] - 2023-04-11
419 - Add worker tasks queue options to pool options.
423 - Fix missing documentation.
425 ## [2.4.6] - 2023-04-10
429 - Ensure one task at a time is executed per worker with tasks queueing enabled.
430 - Properly count worker executing tasks with tasks queueing enabled.
432 ## [2.4.5] - 2023-04-09
436 - Use monotonic high resolution timer for worker tasks runtime.
437 - Add worker tasks median runtime to statistics.
438 - Add worker tasks queue (experimental).
440 ## [2.4.4] - 2023-04-07
444 - Add `PoolEvents` enumeration and `PoolEvent` type.
448 - Destroy worker only on alive check.
450 ## [2.4.3] - 2023-04-07
454 - Fix typedoc generation with inheritance.
456 ## [2.4.2] - 2023-04-06
460 - Add `full` event to dynamic pool.
461 - Keep worker choice strategy in memory for conditional reuse.
465 - Fix possible negative worker key at worker removal in worker choice strategies.
467 ## [2.4.1] - 2023-04-05
471 - Optimize worker choice strategy for dynamic pool.
475 - Ensure dynamic pool does not alter worker choice strategy expected behavior.
477 ## [2.4.0] - 2023-04-04
481 - Add `LESS_BUSY` worker choice strategy.
485 - Optimize worker storage in pool.
486 - Optimize worker alive status check.
487 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
488 - Optimize `LESS_USED` worker choice strategy.
489 - Update benchmarks versus external threads pools.
490 - Optimize tasks usage statistics requirements for worker choice strategy.
494 - Ensure trimmable characters are checked at pool initialization.
495 - Fix message id integer overflow.
496 - Fix pool worker removal in worker choice strategy internals.
497 - Fix package publication with pnpm.
499 ## [2.4.0-3] - 2023-04-04
503 - Add `LESS_BUSY` worker choice strategy.
507 - Optimize worker storage in pool.
508 - Optimize worker alive status check.
509 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
510 - Optimize `LESS_USED` worker choice strategy.
511 - Update benchmarks versus external threads pools.
515 - Ensure trimmable characters are checked at pool initialization.
516 - Fix message id integer overflow.
517 - Fix pool worker removal in worker choice strategy internals.
518 - Fix package publication with pnpm.
520 ## [2.4.0-2] - 2023-04-03
524 - Add `LESS_BUSY` worker choice strategy.
528 - Optimize worker storage in pool.
529 - Optimize worker alive status check.
530 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
531 - Optimize `LESS_USED` worker choice strategy.
535 - Ensure trimmable characters are checked at pool initialization.
536 - Fix message id integer overflow.
537 - Fix pool worker removal in worker choice strategy internals.
538 - Fix package publication with pnpm.
540 ## [2.4.0-1] - 2023-04-03
544 - Add `LESS_BUSY` worker choice strategy.
548 - Optimize worker storage in pool.
549 - Optimize worker alive status check.
550 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
551 - Optimize `LESS_USED` worker choice strategy.
555 - Ensure trimmable characters are checked at pool initialization.
556 - Fix message id integer overflow.
557 - Fix pool worker removal in worker choice strategy internals.
559 ## [2.4.0-0] - 2023-04-03
563 - Add `LESS_BUSY` worker choice strategy.
567 - Optimize worker storage in pool.
568 - Optimize worker alive status check.
569 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
570 - Optimize `LESS_USED` worker choice strategy.
574 - Ensure trimmable characters are checked at pool initialization.
575 - Fix message id integer overflow.
576 - Fix pool worker removal in worker choice strategy internals.
578 ## [2.3.10] - 2023-03-18
582 - Fix package.json `exports` syntax for ESM and CommonJS.
586 - Permit SemVer pre-release publication.
588 ## [2.3.10-2] - 2023-03-18
592 - Fix package.json `exports` syntax for ESM and CommonJS.
594 ## [2.3.10-1] - 2023-03-18
598 - Permit SemVer pre-release publication.
600 ## [2.3.10-0] - 2023-03-18
604 - Fix package.json `exports` syntax for ESM and CommonJS.
606 ## [2.3.9] - 2023-03-18
610 - Introduce ESM module support along with CommonJS one.
614 - Fix brown paper bag bug referencing the same object literal.
616 ## [2.3.8] - 2023-03-18
620 - Switch internal benchmarking code to benny.
621 - Switch to TypeScript 5.x.x.
622 - Switch rollup bundler plugins to core ones.
623 - Switch to TSDoc syntax.
624 - Enforce conventional commits.
628 - Fix random integer generator.
629 - Fix worker choice strategy pool type identification at initialization.
631 ## [2.3.7] - 2022-10-23
635 - Switch to open collective FOSS project funding platform.
636 - Switch to ts-standard linter configuration on TypeScript code.
640 - Fixed missing async on pool execute method.
641 - Fixed typing in TypeScript example.
642 - Fixed types in unit tests.
644 ## [2.3.6] - 2022-10-22
648 - Cleanup pool attributes and methods.
649 - Refine error types thrown.
653 - Fix continuous integration build on windows.
654 - Fix code coverage reporting by using c8 instead of nyc.
656 ## [2.3.5] - 2022-10-21
660 - Improve benchmarks: add IO intensive task workload, add task size option, integrate code into linter.
661 - Optimize tasks usage lookup implementation.
665 - Fix missed pool event emitter type export.
666 - Fix typedoc documentation generation.
668 ## [2.3.4] - 2022-10-17
672 - Fully automate release process with release-it.
676 - Optimize fair share task scheduling algorithm implementation.
677 - Update benchmarks versus external pools results with latest version.
679 ## [2.3.3] - 2022-10-15
683 - Add support for [cluster settings](https://nodejs.org/api/cluster.html#cluster_cluster_settings) in cluster pool options.
685 ## [2.3.2] - 2022-10-14
689 - Optimize fair share worker selection strategy implementation.
693 - Fix WRR worker selection strategy: ensure the condition triggering the round robin can be fulfilled.
695 ## [2.3.1] - 2022-10-13
699 - Pool worker choice strategies:
700 - `WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN` strategy based on weighted round robin scheduling algorithm using tasks execution time for now.
701 - `WorkerChoiceStrategies.FAIR_SHARE` strategy based on fair share scheduling algorithm using tasks execution time for now.
703 ## [2.2.2] - 2022-10-09
707 - Fixed `README.md` file.
709 ## [2.2.1] - 2022-10-08
713 - Dynamic worker choice strategy change at runtime.
715 ## [2.2.0] - 2022-01-05
719 - Support only Node.js version 16.x.x for cluster pool: upstream cluster API have changed on that version.
721 ## [2.1.0] - 2021-08-29
725 - Add an optional pool option `messageHandler` to `PoolOptions<Worker>` for registering a message handler callback on each worker.
729 - `AbstractWorker` class `maxInactiveTime`, `killBehavior` and `async` attributes have been removed in favour of the same ones in the worker options `opts` public attribute.
730 - `AbstractWorker` class `lastTask` attribute have been renamed to `lastTaskTimestamp`.
731 - `AbstractWorker` class `interval` attribute have been renamed to `aliveInterval`.
732 - `AbstractWorker` class cannot be instantiated without specifying the `mainWorker` argument referencing the main worker.
734 ## [2.0.2] - 2021-05-12
738 - Fix `busy` event emission on fixed pool type
740 ## [2.0.1] - 2021-03-16
744 - Check if pool options are properly set.
745 - `busy` event is emitted on all pool types.
747 ## [2.0.0] - 2021-03-01
751 - Now a thread/process by default is not deleted when the task submitted take more time than maxInactiveTime configured (issue #70).
755 - `FullPool` event is now renamed to `busy`.
756 - `maxInactiveTime` on `ThreadWorker` default behavior is now changed, if you want to keep the old behavior set `killBehavior` to `KillBehaviors.HARD`.
757 _Find more details on our JSDoc._
759 - `maxTasks` option on `FixedThreadPool` and `DynamicThreadPool` is now removed since is no more needed.
761 - We changed some internal structures, but you shouldn't be too affected by them as these are internal changes.
763 ### Pool options types declaration merge
765 `FixedThreadPoolOptions` and `DynamicThreadPoolOptions` type declarations have been merged to `PoolOptions<Worker>`.
767 #### New `export` strategy
771 const DynamicThreadPool = require('poolifier/lib/dynamic')
773 const { DynamicThreadPool } = require('poolifier/lib/dynamic')
776 But you should always prefer just using
779 const { DynamicThreadPool } = require('poolifier')
782 #### New type definitions for input data and response
784 For cluster worker and worker-thread pools, you can now only send and receive structured-cloneable data.
785 _This is not a limitation by poolifier but Node.js._
787 #### Public property replacements
789 `numWorkers` property is now `numberOfWorkers`
791 #### Internal (protected) properties and methods renaming
793 These properties are not intended for end users
795 - `id` => `nextMessageId`
797 These methods are not intended for end users
799 - `_chooseWorker` => `chooseWorker`
800 - `_newWorker` => `createWorker`
801 - `_execute` => `internalExecute`
802 - `_chooseWorker` => `chooseWorker`
803 - `_checkAlive` => `checkAlive`
805 - `_runAsync` => `runAsync`
807 ## [1.1.0] - 2020-05-21
811 - ThreadWorker support async functions as option
812 - Various external library patches
814 ## [1.0.0] - 2020-01-24
818 - FixedThreadPool implementation
819 - DynamicThreadPool implementation
820 - WorkerThread implementation to improve developer experience