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 ## [2.6.32] - 2023-08-23
14 - Ensure no task can be executed when the pool is destroyed.
18 - Add `queueMaxSize` option to tasks queue options.
19 - Add O(1) deque implementation implemented with doubly linked list and use it for tasks queueing.
20 - Add tasks stealing algorithm when a worker node queue is back pressured if tasks queueing is enabled.
22 ## [2.6.31] - 2023-08-20
26 - Fix worker choice strategy retries mechanism in some edge cases.
30 - Make orthogonal worker choice strategies tasks distribution and created dynamic worker usage.
31 - Remove the experimental status of the `LEAST_ELU` worker choice strategy.
33 ## [2.6.30] - 2023-08-19
37 - Ensure pool event `backPressure` is emitted.
38 - Ensure pool event `full` is emitted only once.
39 - Ensure worker node cannot be instantiated without proper arguments.
41 ## [2.6.29] - 2023-08-18
45 - Fix race condition between ready and task functions worker message handling at startup.
46 - Fix duplicate task function worker usage statistics computation per task function.
47 - Update task function worker usage statistics if and only if there's at least two different task functions.
48 - Fix race condition at task function worker usage executing task computation leading to negative value.
52 - 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).
53 - Use back pressure detection in worker choice strategies.
54 - Add worker choice strategies retries mechanism if no worker is eligible.
56 ## [2.6.28] - 2023-08-16
60 - Ensure pool workers are properly initialized.
64 - HTTP server pool examples: express-cluster, express-hybrid.
68 - Remove now useless branching in worker hot code path.
70 ## [2.6.27] - 2023-08-15
74 - Add `KillHandler` type definition to exported types.
78 - Add `destroy` event to pool API.
80 ## [2.6.26] - 2023-08-15
84 - Add kill handler to worker options allowing to execute custom code when worker is killed.
85 - Add `listTaskFunctions()` method to pool API.
86 - SMTP server pool example: nodemailer.
88 ## [2.6.25] - 2023-08-13
92 - HTTP server pool examples: fastify-cluster, fastify-hybrid.
93 - WebSocket server pool examples: ws-cluster, ws-hybrid.
95 ## [2.6.24] - 2023-08-12
99 - Add array of transferable objects to the `execute()` method arguments.
100 - WebSocket server pool examples: ws-worker_threads.
102 ## [2.6.23] - 2023-08-11
106 - 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.
110 - HTTP client pool examples: fetch, node-fetch and axios with multiple task functions.
111 - HTTP server pool examples: express-worker_threads, fastify-worker_threads.
113 ## [2.6.22] - 2023-08-10
117 - Add missing `types` field to package.json `exports`.
121 - Structure markdown documentation (PR #811).
123 ## [2.6.21] - 2023-08-03
127 - Improve code documentation.
128 - Code refactoring and cleanup for better maintainability and readability.
130 ## [2.6.20] - 2023-07-21
134 - Fix queued tasks redistribution on error task execution starvation.
135 - Ensure tasks queueing per worker condition is untangled from the pool busyness semantic.
139 - Drastically reduce lookups by worker in the worker nodes.
141 ## [2.6.19] - 2023-07-20
145 - Dedicated internal communication channel for worker_threads pools.
147 ## [2.6.18] - 2023-07-19
151 - Code refactoring and cleanup for better maintainability and readability. Bundle size is a bit smaller.
153 ## [2.6.17] - 2023-07-16
157 - Add `listTaskFunctions()` method to worker API.
159 ## [2.6.16] - 2023-07-12
163 - Fix pool startup detection.
164 - Fix worker task functions handling.
166 ## [2.6.15] - 2023-07-11
170 - Take into account worker node readiness in worker choice strategies.
172 ## [2.6.14] - 2023-07-10
176 - Fix task function statistics tracking.
178 ## [2.6.13] - 2023-07-10
182 - Add per task function statistics tracking.
183 - Add public methods to manipulate the worker task functions at runtime.
185 ## [2.6.12] - 2023-07-09
189 - Workaround import issue with `node:os` module in node 16.x.x.
191 ## [2.6.11] - 2023-07-09
195 - Fix pool readiness semantic.
197 ## [2.6.10] - 2023-07-08
201 - Ensure workers are not recreated on error at pool startup.
205 - Add `ready` and `strategy` fields to pool information.
206 - Add pool event `ready` to notify when the number of workers created in the pool has reached the maximum size expected and are ready.
207 - Add dynamic pool sizing checks.
209 ## [2.6.9] - 2023-07-07
213 - Recreate the right worker type on uncaught exception.
217 - Add minimum and maximum to internal measurement statistics.
218 - Add `runTime` and `waitTime` to pool information.
219 - Check worker inactive time only on dynamic worker.
221 ## [2.6.8] - 2023-07-03
225 - Brown paper bag release to fix version handling in pool information.
227 ## [2.6.7] - 2023-07-03
231 - Ensure worker queued tasks at error are reassigned to other pool workers.
235 - Add pool `utilization` ratio to pool information.
236 - Add `version` to pool information.
237 - Add worker information to worker nodes.
239 ## [2.6.6] - 2023-07-01
243 - Add safe helper `availableParallelism()` to help sizing the pool.
247 - Ensure message handler is only registered in worker.
249 ## [2.6.5] - 2023-06-27
253 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
257 - Artificial version bump to 2.6.5 to workaround publication issue.
258 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
259 - Ensure pool event is emitted before task error promise rejection.
260 - Fix queued tasks count computation.
264 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
266 ## [2.6.4] - 2023-06-27
270 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
274 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
275 - Ensure pool event is emitted before task error promise rejection.
276 - Fix queued tasks count computation.
280 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
282 ## [2.6.3] - 2023-06-19
286 - Ensure no tasks are queued when trying to soft kill a dynamic worker.
287 - Update strategies internals after statistics computation.
291 - Optimize O(1) queue implementation.
293 ## [2.6.2] - 2023-06-12
297 - Fix new worker use after creation in dynamic pool given the current worker choice strategy.
299 ## [2.6.1] - 2023-06-10
303 - Add worker choice strategy documentation: [README.md](./docs/worker-choice-strategies.md).
307 - Fix average statistics computation: ensure failed tasks are not accounted.
309 ## [2.6.0] - 2023-06-09
313 - Add `LEAST_ELU` worker choice strategy (experimental).
314 - Add tasks ELU instead of runtime support to `FAIR_SHARE` worker choice strategy.
318 - Refactor pool worker node usage internals.
319 - Breaking change: refactor worker choice strategy statistics requirements: the syntax of the worker choice strategy options has changed.
320 - Breaking change: pool information `info` property object fields have been renamed.
324 - Fix wait time accounting.
325 - Ensure worker choice strategy `LEAST_BUSY` accounts also tasks wait time.
326 - Ensure worker choice strategy `LEAST_USED` accounts also queued tasks.
328 ## [2.5.4] - 2023-06-07
332 - Add Event Loop Utilization (ELU) statistics to worker tasks usage.
336 - Compute statistics at the worker level only if needed.
337 - Add `worker_threads` options to thread pool options.
341 - Make the `LEAST_BUSY` strategy only relies on task runtime.
343 ## [2.5.3] - 2023-06-04
347 - Refine pool information content.
348 - Limit pool internals public exposure.
350 ## [2.5.2] - 2023-06-02
354 - Add `taskError` pool event for task execution error.
355 - Add pool information `info` property to pool.
356 - Emit pool information on `busy` and `full` pool events.
358 ## [2.5.1] - 2023-06-01
362 - Add pool option `restartWorkerOnError` to restart worker on uncaught error. Default to `true`.
363 - Add `error` pool event for uncaught worker error.
365 ## [2.5.0] - 2023-05-31
369 - Switch pool event emitter to `EventEmitterAsyncResource`.
370 - Add tasks wait time accounting in per worker tasks usage.
371 - Add interleaved weighted round robin `INTERLEAVED_WEIGHTED_ROUND_ROBIN` worker choice strategy (experimental).
375 - Renamed worker choice strategy `LESS_BUSY` to `LEAST_BUSY` and `LESS_USED` to `LEAST_USED`.
377 ## [2.4.14] - 2023-05-09
381 - Ensure no undefined task runtime can land in the tasks history.
382 - Fix median computation implementation once again.
386 - Unit tests for median and queue implementations.
388 ## [2.4.13] - 2023-05-08
392 - Fix worker choice strategy options validation.
393 - Fix fair share worker choice strategy internals update: ensure virtual task end timestamp is computed at task submission.
395 ## [2.4.12] - 2023-05-06
399 - Support multiple task functions per worker.
400 - Add custom worker weights support to worker choice strategies options.
404 - Use O(1) queue implementation for tasks queueing.
408 - Fix median computation implementation.
409 - Fix fair share worker choice strategy internals update.
411 ## [2.4.11] - 2023-04-23
415 - Optimize free worker finding in worker choice strategies.
417 ## [2.4.10] - 2023-04-15
421 - Fix typescript type definition for task function: ensure the input data is optional.
422 - Fix typescript type definition for pool execute(): ensure the input data is optional.
424 ## [2.4.9] - 2023-04-15
428 - Add tasks queue enablement runtime setter to pool.
429 - Add tasks queue options runtime setter to pool.
430 - Add worker choice strategy options runtime setter to pool.
434 - Remove the tasks queuing experimental status.
438 - Fix task function type definition and validation.
439 - Fix worker choice strategy options handling.
441 ## [2.4.8] - 2023-04-12
445 - Fix message between main worker and worker type definition for tasks.
446 - Fix code documentation.
448 ## [2.4.7] - 2023-04-11
452 - Add worker tasks queue options to pool options.
456 - Fix missing documentation.
458 ## [2.4.6] - 2023-04-10
462 - Ensure one task at a time is executed per worker with tasks queueing enabled.
463 - Properly count worker executing tasks with tasks queueing enabled.
465 ## [2.4.5] - 2023-04-09
469 - Use monotonic high resolution timer for worker tasks runtime.
470 - Add worker tasks median runtime to statistics.
471 - Add worker tasks queue (experimental).
473 ## [2.4.4] - 2023-04-07
477 - Add `PoolEvents` enumeration and `PoolEvent` type.
481 - Destroy worker only on alive check.
483 ## [2.4.3] - 2023-04-07
487 - Fix typedoc generation with inheritance.
489 ## [2.4.2] - 2023-04-06
493 - Add `full` event to dynamic pool.
494 - Keep worker choice strategy in memory for conditional reuse.
498 - Fix possible negative worker key at worker removal in worker choice strategies.
500 ## [2.4.1] - 2023-04-05
504 - Optimize worker choice strategy for dynamic pool.
508 - Ensure dynamic pool does not alter worker choice strategy expected behavior.
510 ## [2.4.0] - 2023-04-04
514 - Add `LESS_BUSY` worker choice strategy.
518 - Optimize worker storage in pool.
519 - Optimize worker alive status check.
520 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
521 - Optimize `LESS_USED` worker choice strategy.
522 - Update benchmarks versus external threads pools.
523 - Optimize tasks usage statistics requirements for worker choice strategy.
527 - Ensure trimmable characters are checked at pool initialization.
528 - Fix message id integer overflow.
529 - Fix pool worker removal in worker choice strategy internals.
530 - Fix package publication with pnpm.
532 ## [2.4.0-3] - 2023-04-04
536 - Add `LESS_BUSY` worker choice strategy.
540 - Optimize worker storage in pool.
541 - Optimize worker alive status check.
542 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
543 - Optimize `LESS_USED` worker choice strategy.
544 - Update benchmarks versus external threads pools.
548 - Ensure trimmable characters are checked at pool initialization.
549 - Fix message id integer overflow.
550 - Fix pool worker removal in worker choice strategy internals.
551 - Fix package publication with pnpm.
553 ## [2.4.0-2] - 2023-04-03
557 - Add `LESS_BUSY` worker choice strategy.
561 - Optimize worker storage in pool.
562 - Optimize worker alive status check.
563 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
564 - Optimize `LESS_USED` worker choice strategy.
568 - Ensure trimmable characters are checked at pool initialization.
569 - Fix message id integer overflow.
570 - Fix pool worker removal in worker choice strategy internals.
571 - Fix package publication with pnpm.
573 ## [2.4.0-1] - 2023-04-03
577 - Add `LESS_BUSY` worker choice strategy.
581 - Optimize worker storage in pool.
582 - Optimize worker alive status check.
583 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
584 - Optimize `LESS_USED` worker choice strategy.
588 - Ensure trimmable characters are checked at pool initialization.
589 - Fix message id integer overflow.
590 - Fix pool worker removal in worker choice strategy internals.
592 ## [2.4.0-0] - 2023-04-03
596 - Add `LESS_BUSY` worker choice strategy.
600 - Optimize worker storage in pool.
601 - Optimize worker alive status check.
602 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
603 - Optimize `LESS_USED` worker choice strategy.
607 - Ensure trimmable characters are checked at pool initialization.
608 - Fix message id integer overflow.
609 - Fix pool worker removal in worker choice strategy internals.
611 ## [2.3.10] - 2023-03-18
615 - Fix package.json `exports` syntax for ESM and CommonJS.
619 - Permit SemVer pre-release publication.
621 ## [2.3.10-2] - 2023-03-18
625 - Fix package.json `exports` syntax for ESM and CommonJS.
627 ## [2.3.10-1] - 2023-03-18
631 - Permit SemVer pre-release publication.
633 ## [2.3.10-0] - 2023-03-18
637 - Fix package.json `exports` syntax for ESM and CommonJS.
639 ## [2.3.9] - 2023-03-18
643 - Introduce ESM module support along with CommonJS one.
647 - Fix brown paper bag bug referencing the same object literal.
649 ## [2.3.8] - 2023-03-18
653 - Switch internal benchmarking code to benny.
654 - Switch to TypeScript 5.x.x.
655 - Switch rollup bundler plugins to core ones.
656 - Switch to TSDoc syntax.
657 - Enforce conventional commits.
661 - Fix random integer generator.
662 - Fix worker choice strategy pool type identification at initialization.
664 ## [2.3.7] - 2022-10-23
668 - Switch to open collective FOSS project funding platform.
669 - Switch to ts-standard linter configuration on TypeScript code.
673 - Fixed missing async on pool execute method.
674 - Fixed typing in TypeScript example.
675 - Fixed types in unit tests.
677 ## [2.3.6] - 2022-10-22
681 - Cleanup pool attributes and methods.
682 - Refine error types thrown.
686 - Fix continuous integration build on windows.
687 - Fix code coverage reporting by using c8 instead of nyc.
689 ## [2.3.5] - 2022-10-21
693 - Improve benchmarks: add IO intensive task workload, add task size option, integrate code into linter.
694 - Optimize tasks usage lookup implementation.
698 - Fix missed pool event emitter type export.
699 - Fix typedoc documentation generation.
701 ## [2.3.4] - 2022-10-17
705 - Fully automate release process with release-it.
709 - Optimize fair share task scheduling algorithm implementation.
710 - Update benchmarks versus external pools results with latest version.
712 ## [2.3.3] - 2022-10-15
716 - Add support for [cluster settings](https://nodejs.org/api/cluster.html#cluster_cluster_settings) in cluster pool options.
718 ## [2.3.2] - 2022-10-14
722 - Optimize fair share worker selection strategy implementation.
726 - Fix WRR worker selection strategy: ensure the condition triggering the round robin can be fulfilled.
728 ## [2.3.1] - 2022-10-13
732 - Pool worker choice strategies:
733 - `WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN` strategy based on weighted round robin scheduling algorithm using tasks execution time for now.
734 - `WorkerChoiceStrategies.FAIR_SHARE` strategy based on fair share scheduling algorithm using tasks execution time for now.
736 ## [2.2.2] - 2022-10-09
740 - Fixed `README.md` file.
742 ## [2.2.1] - 2022-10-08
746 - Dynamic worker choice strategy change at runtime.
748 ## [2.2.0] - 2022-01-05
752 - Support only Node.js version 16.x.x for cluster pool: upstream cluster API have changed on that version.
754 ## [2.1.0] - 2021-08-29
758 - Add an optional pool option `messageHandler` to `PoolOptions<Worker>` for registering a message handler callback on each worker.
762 - `AbstractWorker` class `maxInactiveTime`, `killBehavior` and `async` attributes have been removed in favour of the same ones in the worker options `opts` public attribute.
763 - `AbstractWorker` class `lastTask` attribute have been renamed to `lastTaskTimestamp`.
764 - `AbstractWorker` class `interval` attribute have been renamed to `aliveInterval`.
765 - `AbstractWorker` class cannot be instantiated without specifying the `mainWorker` argument referencing the main worker.
767 ## [2.0.2] - 2021-05-12
771 - Fix `busy` event emission on fixed pool type
773 ## [2.0.1] - 2021-03-16
777 - Check if pool options are properly set.
778 - `busy` event is emitted on all pool types.
780 ## [2.0.0] - 2021-03-01
784 - Now a thread/process by default is not deleted when the task submitted take more time than maxInactiveTime configured (issue #70).
788 - `FullPool` event is now renamed to `busy`.
789 - `maxInactiveTime` on `ThreadWorker` default behavior is now changed, if you want to keep the old behavior set `killBehavior` to `KillBehaviors.HARD`.
790 _Find more details on our JSDoc._
792 - `maxTasks` option on `FixedThreadPool` and `DynamicThreadPool` is now removed since is no more needed.
794 - We changed some internal structures, but you shouldn't be too affected by them as these are internal changes.
796 ### Pool options types declaration merge
798 `FixedThreadPoolOptions` and `DynamicThreadPoolOptions` type declarations have been merged to `PoolOptions<Worker>`.
800 #### New `export` strategy
804 const DynamicThreadPool = require('poolifier/lib/dynamic')
806 const { DynamicThreadPool } = require('poolifier/lib/dynamic')
809 But you should always prefer just using
812 const { DynamicThreadPool } = require('poolifier')
815 #### New type definitions for input data and response
817 For cluster worker and worker-thread pools, you can now only send and receive structured-cloneable data.
818 _This is not a limitation by poolifier but Node.js._
820 #### Public property replacements
822 `numWorkers` property is now `numberOfWorkers`
824 #### Internal (protected) properties and methods renaming
826 These properties are not intended for end users
828 - `id` => `nextMessageId`
830 These methods are not intended for end users
832 - `_chooseWorker` => `chooseWorker`
833 - `_newWorker` => `createWorker`
834 - `_execute` => `internalExecute`
835 - `_chooseWorker` => `chooseWorker`
836 - `_checkAlive` => `checkAlive`
838 - `_runAsync` => `runAsync`
840 ## [1.1.0] - 2020-05-21
844 - ThreadWorker support async functions as option
845 - Various external library patches
847 ## [1.0.0] - 2020-01-24
851 - FixedThreadPool implementation
852 - DynamicThreadPool implementation
853 - WorkerThread implementation to improve developer experience