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 - Add `queueMaxSize` option to tasks queue options.
13 - Add O(1) deque implementation implemented with doubly linked list and use it for tasks queueing.
15 ## [2.6.31] - 2023-08-20
19 - Fix worker choice strategy retries mechanism in some edge cases.
23 - Make orthogonal worker choice strategies tasks distribution and created dynamic worker usage.
24 - Remove the experimental status of the `LEAST_ELU` worker choice strategy.
26 ## [2.6.30] - 2023-08-19
30 - Ensure pool event `backPressure` is emitted.
31 - Ensure pool event `full` is emitted only once.
32 - Ensure worker node cannot be instantiated without proper arguments.
34 ## [2.6.29] - 2023-08-18
38 - Fix race condition between ready and task functions worker message handling at startup.
39 - Fix duplicate task function worker usage statistics computation per task function.
40 - Update task function worker usage statistics if and only if there's at least two different task functions.
41 - Fix race condition at task function worker usage executing task computation leading to negative value.
45 - 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).
46 - Use back pressure detection in worker choice strategies.
47 - Add worker choice strategies retries mechanism if no worker is eligible.
49 ## [2.6.28] - 2023-08-16
53 - Ensure pool workers are properly initialized.
57 - HTTP server pool examples: express-cluster, express-hybrid.
61 - Remove now useless branching in worker hot code path.
63 ## [2.6.27] - 2023-08-15
67 - Add `KillHandler` type definition to exported types.
71 - Add `destroy` event to pool API.
73 ## [2.6.26] - 2023-08-15
77 - Add kill handler to worker options allowing to execute custom code when worker is killed.
78 - Add `listTaskFunctions()` method to pool API.
79 - SMTP server pool example: nodemailer.
81 ## [2.6.25] - 2023-08-13
85 - HTTP server pool examples: fastify-cluster, fastify-hybrid.
86 - WebSocket server pool examples: ws-cluster, ws-hybrid.
88 ## [2.6.24] - 2023-08-12
92 - Add array of transferable objects to the `execute()` method arguments.
93 - WebSocket server pool examples: ws-worker_threads.
95 ## [2.6.23] - 2023-08-11
99 - 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.
103 - HTTP client pool examples: fetch, node-fetch and axios with multiple task functions.
104 - HTTP server pool examples: express-worker_threads, fastify-worker_threads.
106 ## [2.6.22] - 2023-08-10
110 - Add missing `types` field to package.json `exports`.
114 - Structure markdown documentation (PR #811).
116 ## [2.6.21] - 2023-08-03
120 - Improve code documentation.
121 - Code refactoring and cleanup for better maintainability and readability.
123 ## [2.6.20] - 2023-07-21
127 - Fix queued tasks redistribution on error task execution starvation.
128 - Ensure tasks queueing per worker condition is untangled from the pool busyness semantic.
132 - Drastically reduce lookups by worker in the worker nodes.
134 ## [2.6.19] - 2023-07-20
138 - Dedicated internal communication channel for worker_threads pools.
140 ## [2.6.18] - 2023-07-19
144 - Code refactoring and cleanup for better maintainability and readability. Bundle size is a bit smaller.
146 ## [2.6.17] - 2023-07-16
150 - Add `listTaskFunctions()` method to worker API.
152 ## [2.6.16] - 2023-07-12
156 - Fix pool startup detection.
157 - Fix worker task functions handling.
159 ## [2.6.15] - 2023-07-11
163 - Take into account worker node readiness in worker choice strategies.
165 ## [2.6.14] - 2023-07-10
169 - Fix task function statistics tracking.
171 ## [2.6.13] - 2023-07-10
175 - Add per task function statistics tracking.
176 - Add public methods to manipulate the worker task functions at runtime.
178 ## [2.6.12] - 2023-07-09
182 - Workaround import issue with `node:os` module in node 16.x.x.
184 ## [2.6.11] - 2023-07-09
188 - Fix pool readiness semantic.
190 ## [2.6.10] - 2023-07-08
194 - Ensure workers are not recreated on error at pool startup.
198 - Add `ready` and `strategy` fields to pool information.
199 - Add pool event `ready` to notify when the number of workers created in the pool has reached the maximum size expected and are ready.
200 - Add dynamic pool sizing checks.
202 ## [2.6.9] - 2023-07-07
206 - Recreate the right worker type on uncaught exception.
210 - Add minimum and maximum to internal measurement statistics.
211 - Add `runTime` and `waitTime` to pool information.
212 - Check worker inactive time only on dynamic worker.
214 ## [2.6.8] - 2023-07-03
218 - Brown paper bag release to fix version handling in pool information.
220 ## [2.6.7] - 2023-07-03
224 - Ensure worker queued tasks at error are reassigned to other pool workers.
228 - Add pool `utilization` ratio to pool information.
229 - Add `version` to pool information.
230 - Add worker information to worker nodes.
232 ## [2.6.6] - 2023-07-01
236 - Add safe helper `availableParallelism()` to help sizing the pool.
240 - Ensure message handler is only registered in worker.
242 ## [2.6.5] - 2023-06-27
246 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
250 - Artificial version bump to 2.6.5 to workaround publication issue.
251 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
252 - Ensure pool event is emitted before task error promise rejection.
253 - Fix queued tasks count computation.
257 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
259 ## [2.6.4] - 2023-06-27
263 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
267 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
268 - Ensure pool event is emitted before task error promise rejection.
269 - Fix queued tasks count computation.
273 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
275 ## [2.6.3] - 2023-06-19
279 - Ensure no tasks are queued when trying to soft kill a dynamic worker.
280 - Update strategies internals after statistics computation.
284 - Optimize O(1) queue implementation.
286 ## [2.6.2] - 2023-06-12
290 - Fix new worker use after creation in dynamic pool given the current worker choice strategy.
292 ## [2.6.1] - 2023-06-10
296 - Add worker choice strategy documentation: [README.md](./docs/worker-choice-strategies.md).
300 - Fix average statistics computation: ensure failed tasks are not accounted.
302 ## [2.6.0] - 2023-06-09
306 - Add `LEAST_ELU` worker choice strategy (experimental).
307 - Add tasks ELU instead of runtime support to `FAIR_SHARE` worker choice strategy.
311 - Refactor pool worker node usage internals.
312 - Breaking change: refactor worker choice strategy statistics requirements: the syntax of the worker choice strategy options has changed.
313 - Breaking change: pool information `info` property object fields have been renamed.
317 - Fix wait time accounting.
318 - Ensure worker choice strategy `LEAST_BUSY` accounts also tasks wait time.
319 - Ensure worker choice strategy `LEAST_USED` accounts also queued tasks.
321 ## [2.5.4] - 2023-06-07
325 - Add Event Loop Utilization (ELU) statistics to worker tasks usage.
329 - Compute statistics at the worker level only if needed.
330 - Add `worker_threads` options to thread pool options.
334 - Make the `LEAST_BUSY` strategy only relies on task runtime.
336 ## [2.5.3] - 2023-06-04
340 - Refine pool information content.
341 - Limit pool internals public exposure.
343 ## [2.5.2] - 2023-06-02
347 - Add `taskError` pool event for task execution error.
348 - Add pool information `info` property to pool.
349 - Emit pool information on `busy` and `full` pool events.
351 ## [2.5.1] - 2023-06-01
355 - Add pool option `restartWorkerOnError` to restart worker on uncaught error. Default to `true`.
356 - Add `error` pool event for uncaught worker error.
358 ## [2.5.0] - 2023-05-31
362 - Switch pool event emitter to `EventEmitterAsyncResource`.
363 - Add tasks wait time accounting in per worker tasks usage.
364 - Add interleaved weighted round robin `INTERLEAVED_WEIGHTED_ROUND_ROBIN` worker choice strategy (experimental).
368 - Renamed worker choice strategy `LESS_BUSY` to `LEAST_BUSY` and `LESS_USED` to `LEAST_USED`.
370 ## [2.4.14] - 2023-05-09
374 - Ensure no undefined task runtime can land in the tasks history.
375 - Fix median computation implementation once again.
379 - Unit tests for median and queue implementations.
381 ## [2.4.13] - 2023-05-08
385 - Fix worker choice strategy options validation.
386 - Fix fair share worker choice strategy internals update: ensure virtual task end timestamp is computed at task submission.
388 ## [2.4.12] - 2023-05-06
392 - Support multiple task functions per worker.
393 - Add custom worker weights support to worker choice strategies options.
397 - Use O(1) queue implementation for tasks queueing.
401 - Fix median computation implementation.
402 - Fix fair share worker choice strategy internals update.
404 ## [2.4.11] - 2023-04-23
408 - Optimize free worker finding in worker choice strategies.
410 ## [2.4.10] - 2023-04-15
414 - Fix typescript type definition for task function: ensure the input data is optional.
415 - Fix typescript type definition for pool execute(): ensure the input data is optional.
417 ## [2.4.9] - 2023-04-15
421 - Add tasks queue enablement runtime setter to pool.
422 - Add tasks queue options runtime setter to pool.
423 - Add worker choice strategy options runtime setter to pool.
427 - Remove the tasks queuing experimental status.
431 - Fix task function type definition and validation.
432 - Fix worker choice strategy options handling.
434 ## [2.4.8] - 2023-04-12
438 - Fix message between main worker and worker type definition for tasks.
439 - Fix code documentation.
441 ## [2.4.7] - 2023-04-11
445 - Add worker tasks queue options to pool options.
449 - Fix missing documentation.
451 ## [2.4.6] - 2023-04-10
455 - Ensure one task at a time is executed per worker with tasks queueing enabled.
456 - Properly count worker executing tasks with tasks queueing enabled.
458 ## [2.4.5] - 2023-04-09
462 - Use monotonic high resolution timer for worker tasks runtime.
463 - Add worker tasks median runtime to statistics.
464 - Add worker tasks queue (experimental).
466 ## [2.4.4] - 2023-04-07
470 - Add `PoolEvents` enumeration and `PoolEvent` type.
474 - Destroy worker only on alive check.
476 ## [2.4.3] - 2023-04-07
480 - Fix typedoc generation with inheritance.
482 ## [2.4.2] - 2023-04-06
486 - Add `full` event to dynamic pool.
487 - Keep worker choice strategy in memory for conditional reuse.
491 - Fix possible negative worker key at worker removal in worker choice strategies.
493 ## [2.4.1] - 2023-04-05
497 - Optimize worker choice strategy for dynamic pool.
501 - Ensure dynamic pool does not alter worker choice strategy expected behavior.
503 ## [2.4.0] - 2023-04-04
507 - Add `LESS_BUSY` worker choice strategy.
511 - Optimize worker storage in pool.
512 - Optimize worker alive status check.
513 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
514 - Optimize `LESS_USED` worker choice strategy.
515 - Update benchmarks versus external threads pools.
516 - Optimize tasks usage statistics requirements for worker choice strategy.
520 - Ensure trimmable characters are checked at pool initialization.
521 - Fix message id integer overflow.
522 - Fix pool worker removal in worker choice strategy internals.
523 - Fix package publication with pnpm.
525 ## [2.4.0-3] - 2023-04-04
529 - Add `LESS_BUSY` worker choice strategy.
533 - Optimize worker storage in pool.
534 - Optimize worker alive status check.
535 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
536 - Optimize `LESS_USED` worker choice strategy.
537 - Update benchmarks versus external threads pools.
541 - Ensure trimmable characters are checked at pool initialization.
542 - Fix message id integer overflow.
543 - Fix pool worker removal in worker choice strategy internals.
544 - Fix package publication with pnpm.
546 ## [2.4.0-2] - 2023-04-03
550 - Add `LESS_BUSY` worker choice strategy.
554 - Optimize worker storage in pool.
555 - Optimize worker alive status check.
556 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
557 - Optimize `LESS_USED` worker choice strategy.
561 - Ensure trimmable characters are checked at pool initialization.
562 - Fix message id integer overflow.
563 - Fix pool worker removal in worker choice strategy internals.
564 - Fix package publication with pnpm.
566 ## [2.4.0-1] - 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 ## [2.4.0-0] - 2023-04-03
589 - Add `LESS_BUSY` worker choice strategy.
593 - Optimize worker storage in pool.
594 - Optimize worker alive status check.
595 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
596 - Optimize `LESS_USED` worker choice strategy.
600 - Ensure trimmable characters are checked at pool initialization.
601 - Fix message id integer overflow.
602 - Fix pool worker removal in worker choice strategy internals.
604 ## [2.3.10] - 2023-03-18
608 - Fix package.json `exports` syntax for ESM and CommonJS.
612 - Permit SemVer pre-release publication.
614 ## [2.3.10-2] - 2023-03-18
618 - Fix package.json `exports` syntax for ESM and CommonJS.
620 ## [2.3.10-1] - 2023-03-18
624 - Permit SemVer pre-release publication.
626 ## [2.3.10-0] - 2023-03-18
630 - Fix package.json `exports` syntax for ESM and CommonJS.
632 ## [2.3.9] - 2023-03-18
636 - Introduce ESM module support along with CommonJS one.
640 - Fix brown paper bag bug referencing the same object literal.
642 ## [2.3.8] - 2023-03-18
646 - Switch internal benchmarking code to benny.
647 - Switch to TypeScript 5.x.x.
648 - Switch rollup bundler plugins to core ones.
649 - Switch to TSDoc syntax.
650 - Enforce conventional commits.
654 - Fix random integer generator.
655 - Fix worker choice strategy pool type identification at initialization.
657 ## [2.3.7] - 2022-10-23
661 - Switch to open collective FOSS project funding platform.
662 - Switch to ts-standard linter configuration on TypeScript code.
666 - Fixed missing async on pool execute method.
667 - Fixed typing in TypeScript example.
668 - Fixed types in unit tests.
670 ## [2.3.6] - 2022-10-22
674 - Cleanup pool attributes and methods.
675 - Refine error types thrown.
679 - Fix continuous integration build on windows.
680 - Fix code coverage reporting by using c8 instead of nyc.
682 ## [2.3.5] - 2022-10-21
686 - Improve benchmarks: add IO intensive task workload, add task size option, integrate code into linter.
687 - Optimize tasks usage lookup implementation.
691 - Fix missed pool event emitter type export.
692 - Fix typedoc documentation generation.
694 ## [2.3.4] - 2022-10-17
698 - Fully automate release process with release-it.
702 - Optimize fair share task scheduling algorithm implementation.
703 - Update benchmarks versus external pools results with latest version.
705 ## [2.3.3] - 2022-10-15
709 - Add support for [cluster settings](https://nodejs.org/api/cluster.html#cluster_cluster_settings) in cluster pool options.
711 ## [2.3.2] - 2022-10-14
715 - Optimize fair share worker selection strategy implementation.
719 - Fix WRR worker selection strategy: ensure the condition triggering the round robin can be fulfilled.
721 ## [2.3.1] - 2022-10-13
725 - Pool worker choice strategies:
726 - `WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN` strategy based on weighted round robin scheduling algorithm using tasks execution time for now.
727 - `WorkerChoiceStrategies.FAIR_SHARE` strategy based on fair share scheduling algorithm using tasks execution time for now.
729 ## [2.2.2] - 2022-10-09
733 - Fixed `README.md` file.
735 ## [2.2.1] - 2022-10-08
739 - Dynamic worker choice strategy change at runtime.
741 ## [2.2.0] - 2022-01-05
745 - Support only Node.js version 16.x.x for cluster pool: upstream cluster API have changed on that version.
747 ## [2.1.0] - 2021-08-29
751 - Add an optional pool option `messageHandler` to `PoolOptions<Worker>` for registering a message handler callback on each worker.
755 - `AbstractWorker` class `maxInactiveTime`, `killBehavior` and `async` attributes have been removed in favour of the same ones in the worker options `opts` public attribute.
756 - `AbstractWorker` class `lastTask` attribute have been renamed to `lastTaskTimestamp`.
757 - `AbstractWorker` class `interval` attribute have been renamed to `aliveInterval`.
758 - `AbstractWorker` class cannot be instantiated without specifying the `mainWorker` argument referencing the main worker.
760 ## [2.0.2] - 2021-05-12
764 - Fix `busy` event emission on fixed pool type
766 ## [2.0.1] - 2021-03-16
770 - Check if pool options are properly set.
771 - `busy` event is emitted on all pool types.
773 ## [2.0.0] - 2021-03-01
777 - Now a thread/process by default is not deleted when the task submitted take more time than maxInactiveTime configured (issue #70).
781 - `FullPool` event is now renamed to `busy`.
782 - `maxInactiveTime` on `ThreadWorker` default behavior is now changed, if you want to keep the old behavior set `killBehavior` to `KillBehaviors.HARD`.
783 _Find more details on our JSDoc._
785 - `maxTasks` option on `FixedThreadPool` and `DynamicThreadPool` is now removed since is no more needed.
787 - We changed some internal structures, but you shouldn't be too affected by them as these are internal changes.
789 ### Pool options types declaration merge
791 `FixedThreadPoolOptions` and `DynamicThreadPoolOptions` type declarations have been merged to `PoolOptions<Worker>`.
793 #### New `export` strategy
797 const DynamicThreadPool = require('poolifier/lib/dynamic')
799 const { DynamicThreadPool } = require('poolifier/lib/dynamic')
802 But you should always prefer just using
805 const { DynamicThreadPool } = require('poolifier')
808 #### New type definitions for input data and response
810 For cluster worker and worker-thread pools, you can now only send and receive structured-cloneable data.
811 _This is not a limitation by poolifier but Node.js._
813 #### Public property replacements
815 `numWorkers` property is now `numberOfWorkers`
817 #### Internal (protected) properties and methods renaming
819 These properties are not intended for end users
821 - `id` => `nextMessageId`
823 These methods are not intended for end users
825 - `_chooseWorker` => `chooseWorker`
826 - `_newWorker` => `createWorker`
827 - `_execute` => `internalExecute`
828 - `_chooseWorker` => `chooseWorker`
829 - `_checkAlive` => `checkAlive`
831 - `_runAsync` => `runAsync`
833 ## [1.1.0] - 2020-05-21
837 - ThreadWorker support async functions as option
838 - Various external library patches
840 ## [1.0.0] - 2020-01-24
844 - FixedThreadPool implementation
845 - DynamicThreadPool implementation
846 - WorkerThread implementation to improve developer experience