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 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.
18 - Add back pressure detection on the worker node queue. Event `backPressure` is emitted all worker node queues are full (size > poolMaxSize^2).
19 - Use back pressure detection in worker choice strategies.
20 - Add worker choice strategies retries mechanism if no worker is eligible.
22 ## [2.6.28] - 2023-08-16
26 - Ensure pool workers are properly initialized.
30 - HTTP server pool examples: express-cluster, express-hybrid.
34 - Remove now useless branching in worker hot code path.
36 ## [2.6.27] - 2023-08-15
40 - Add `KillHandler` type definition to exported types.
44 - Add `destroy` event to pool API.
46 ## [2.6.26] - 2023-08-15
50 - Add kill handler to worker options allowing to execute custom code when worker is killed.
51 - Add `listTaskFunctions()` method to pool API.
52 - SMTP server pool example: nodemailer.
54 ## [2.6.25] - 2023-08-13
58 - HTTP server pool examples: fastify-cluster, fastify-hybrid.
59 - WebSocket server pool examples: ws-cluster, ws-hybrid.
61 ## [2.6.24] - 2023-08-12
65 - Add array of transferable objects to the `execute()` method arguments.
66 - WebSocket server pool examples: ws-worker_threads.
68 ## [2.6.23] - 2023-08-11
72 - 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.
76 - HTTP client pool examples: fetch, node-fetch and axios with multiple task functions.
77 - HTTP server pool examples: express-worker_threads, fastify-worker_threads.
79 ## [2.6.22] - 2023-08-10
83 - Add missing `types` field to package.json `exports`.
87 - Structure markdown documentation (PR #811).
89 ## [2.6.21] - 2023-08-03
93 - Improve code documentation.
94 - Code refactoring and cleanup for better maintainability and readability.
96 ## [2.6.20] - 2023-07-21
100 - Fix queued tasks redistribution on error task execution starvation.
101 - Ensure task queueing per worker condition is untangled from the pool busyness semantic.
105 - Drastically reduce lookups by worker in the worker nodes.
107 ## [2.6.19] - 2023-07-20
111 - Dedicated internal communication channel for worker_threads pools.
113 ## [2.6.18] - 2023-07-19
117 - Code refactoring and cleanup for better maintainability and readability. Bundle size is a bit smaller.
119 ## [2.6.17] - 2023-07-16
123 - Add `listTaskFunctions()` method to worker API.
125 ## [2.6.16] - 2023-07-12
129 - Fix pool startup detection.
130 - Fix worker task functions handling.
132 ## [2.6.15] - 2023-07-11
136 - Take into account worker node readiness in worker choice strategies.
138 ## [2.6.14] - 2023-07-10
142 - Fix task function statistics tracking.
144 ## [2.6.13] - 2023-07-10
148 - Add per task function statistics tracking.
149 - Add public methods to manipulate the worker task functions at runtime.
151 ## [2.6.12] - 2023-07-09
155 - Workaround import issue with `node:os` module in node 16.x.x.
157 ## [2.6.11] - 2023-07-09
161 - Fix pool readiness semantic.
163 ## [2.6.10] - 2023-07-08
167 - Ensure workers are not recreated on error at pool startup.
171 - Add `ready` and `strategy` fields to pool information.
172 - Add pool event `ready` to notify when the number of workers created in the pool has reached the maximum size expected and are ready.
173 - Add dynamic pool sizing checks.
175 ## [2.6.9] - 2023-07-07
179 - Recreate the right worker type on uncaught exception.
183 - Add minimum and maximum to internal measurement statistics.
184 - Add `runTime` and `waitTime` to pool information.
185 - Check worker inactive time only on dynamic worker.
187 ## [2.6.8] - 2023-07-03
191 - Brown paper bag release to fix version handling in pool information.
193 ## [2.6.7] - 2023-07-03
197 - Ensure worker queued tasks at error are reassigned to other pool workers.
201 - Add pool `utilization` ratio to pool information.
202 - Add `version` to pool information.
203 - Add worker information to worker nodes.
205 ## [2.6.6] - 2023-07-01
209 - Add safe helper `availableParallelism` to help sizing the pool.
213 - Ensure message handler is only registered in worker.
215 ## [2.6.5] - 2023-06-27
219 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
223 - Artificial version bump to 2.6.5 to workaround publication issue.
224 - Ensure cluster pool destroy() gracefully shutdowns worker's server.
225 - Ensure pool event is emitted before task error promise rejection.
226 - Fix queued tasks count computation.
230 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
232 ## [2.6.4] - 2023-06-27
236 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
240 - Ensure cluster pool destroy() gracefully shutdowns worker's server.
241 - Ensure pool event is emitted before task error promise rejection.
242 - Fix queued tasks count computation.
246 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
248 ## [2.6.3] - 2023-06-19
252 - Ensure no tasks are queued when trying to soft kill a dynamic worker.
253 - Update strategies internals after statistics computation.
257 - Optimize O(1) queue implementation.
259 ## [2.6.2] - 2023-06-12
263 - Fix new worker use after creation in dynamic pool given the current worker choice strategy.
265 ## [2.6.1] - 2023-06-10
269 - Add worker choice strategy documentation: [README.md](./docs/worker-choice-strategies.md).
273 - Fix average statistics computation: ensure failed tasks are not accounted.
275 ## [2.6.0] - 2023-06-09
279 - Add `LEAST_ELU` worker choice strategy (experimental).
280 - Add tasks ELU instead of runtime support to `FAIR_SHARE` worker choice strategy.
284 - Refactor pool worker node usage internals.
285 - Breaking change: refactor worker choice strategy statistics requirements: the syntax of the worker choice strategy options has changed.
286 - Breaking change: pool information `info` property object fields have been renamed.
290 - Fix wait time accounting.
291 - Ensure worker choice strategy `LEAST_BUSY` accounts also tasks wait time.
292 - Ensure worker choice strategy `LEAST_USED` accounts also queued tasks.
294 ## [2.5.4] - 2023-06-07
298 - Add Event Loop Utilization (ELU) statistics to worker tasks usage.
302 - Compute statistics at the worker level only if needed.
303 - Add `worker_threads` options to thread pool options.
307 - Make the `LEAST_BUSY` strategy only relies on task runtime.
309 ## [2.5.3] - 2023-06-04
313 - Refine pool information content.
314 - Limit pool internals public exposure.
316 ## [2.5.2] - 2023-06-02
320 - Add `taskError` pool event for task execution error.
321 - Add pool information `info` property to pool.
322 - Emit pool information on `busy` and `full` pool events.
324 ## [2.5.1] - 2023-06-01
328 - Add pool option `restartWorkerOnError` to restart worker on uncaught error. Default to `true`.
329 - Add `error` pool event for uncaught worker error.
331 ## [2.5.0] - 2023-05-31
335 - Switch pool event emitter to `EventEmitterAsyncResource`.
336 - Add tasks wait time accounting in per worker tasks usage.
337 - Add interleaved weighted round robin `INTERLEAVED_WEIGHTED_ROUND_ROBIN` worker choice strategy (experimental).
341 - Renamed worker choice strategy `LESS_BUSY` to `LEAST_BUSY` and `LESS_USED` to `LEAST_USED`.
343 ## [2.4.14] - 2023-05-09
347 - Ensure no undefined task runtime can land in the tasks history.
348 - Fix median computation implementation once again.
352 - Unit tests for median and queue implementations.
354 ## [2.4.13] - 2023-05-08
358 - Fix worker choice strategy options validation.
359 - Fix fair share worker choice strategy internals update: ensure virtual task end timestamp is computed at task submission.
361 ## [2.4.12] - 2023-05-06
365 - Support multiple task functions per worker.
366 - Add custom worker weights support to worker choice strategies options.
370 - Use O(1) queue implementation for tasks queueing.
374 - Fix median computation implementation.
375 - Fix fair share worker choice strategy internals update.
377 ## [2.4.11] - 2023-04-23
381 - Optimize free worker finding in worker choice strategies.
383 ## [2.4.10] - 2023-04-15
387 - Fix typescript type definition for task function: ensure the input data is optional.
388 - Fix typescript type definition for pool execute(): ensure the input data is optional.
390 ## [2.4.9] - 2023-04-15
394 - Add tasks queue enablement runtime setter to pool.
395 - Add tasks queue options runtime setter to pool.
396 - Add worker choice strategy options runtime setter to pool.
400 - Remove the tasks queuing experimental status.
404 - Fix task function type definition and validation.
405 - Fix worker choice strategy options handling.
407 ## [2.4.8] - 2023-04-12
411 - Fix message between main worker and worker type definition for tasks.
412 - Fix code documentation.
414 ## [2.4.7] - 2023-04-11
418 - Add worker tasks queue options to pool options.
422 - Fix missing documentation.
424 ## [2.4.6] - 2023-04-10
428 - Ensure one task at a time is executed per worker with tasks queueing enabled.
429 - Properly count worker executing tasks with tasks queueing enabled.
431 ## [2.4.5] - 2023-04-09
435 - Use monotonic high resolution timer for worker tasks runtime.
436 - Add worker tasks median runtime to statistics.
437 - Add worker tasks queue (experimental).
439 ## [2.4.4] - 2023-04-07
443 - Add `PoolEvents` enumeration and `PoolEvent` type.
447 - Destroy worker only on alive check.
449 ## [2.4.3] - 2023-04-07
453 - Fix typedoc generation with inheritance.
455 ## [2.4.2] - 2023-04-06
459 - Add `full` event to dynamic pool.
460 - Keep worker choice strategy in memory for conditional reuse.
464 - Fix possible negative worker key at worker removal in worker choice strategies.
466 ## [2.4.1] - 2023-04-05
470 - Optimize worker choice strategy for dynamic pool.
474 - Ensure dynamic pool does not alter worker choice strategy expected behavior.
476 ## [2.4.0] - 2023-04-04
480 - Add `LESS_BUSY` worker choice strategy.
484 - Optimize worker storage in pool.
485 - Optimize worker alive status check.
486 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
487 - Optimize `LESS_USED` worker choice strategy.
488 - Update benchmarks versus external threads pools.
489 - Optimize tasks usage statistics requirements for worker choice strategy.
493 - Ensure trimmable characters are checked at pool initialization.
494 - Fix message id integer overflow.
495 - Fix pool worker removal in worker choice strategy internals.
496 - Fix package publication with pnpm.
498 ## [2.4.0-3] - 2023-04-04
502 - Add `LESS_BUSY` worker choice strategy.
506 - Optimize worker storage in pool.
507 - Optimize worker alive status check.
508 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
509 - Optimize `LESS_USED` worker choice strategy.
510 - Update benchmarks versus external threads pools.
514 - Ensure trimmable characters are checked at pool initialization.
515 - Fix message id integer overflow.
516 - Fix pool worker removal in worker choice strategy internals.
517 - Fix package publication with pnpm.
519 ## [2.4.0-2] - 2023-04-03
523 - Add `LESS_BUSY` worker choice strategy.
527 - Optimize worker storage in pool.
528 - Optimize worker alive status check.
529 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
530 - Optimize `LESS_USED` worker choice strategy.
534 - Ensure trimmable characters are checked at pool initialization.
535 - Fix message id integer overflow.
536 - Fix pool worker removal in worker choice strategy internals.
537 - Fix package publication with pnpm.
539 ## [2.4.0-1] - 2023-04-03
543 - Add `LESS_BUSY` worker choice strategy.
547 - Optimize worker storage in pool.
548 - Optimize worker alive status check.
549 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
550 - Optimize `LESS_USED` worker choice strategy.
554 - Ensure trimmable characters are checked at pool initialization.
555 - Fix message id integer overflow.
556 - Fix pool worker removal in worker choice strategy internals.
558 ## [2.4.0-0] - 2023-04-03
562 - Add `LESS_BUSY` worker choice strategy.
566 - Optimize worker storage in pool.
567 - Optimize worker alive status check.
568 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
569 - Optimize `LESS_USED` worker choice strategy.
573 - Ensure trimmable characters are checked at pool initialization.
574 - Fix message id integer overflow.
575 - Fix pool worker removal in worker choice strategy internals.
577 ## [2.3.10] - 2023-03-18
581 - Fix package.json `exports` syntax for ESM and CommonJS.
585 - Permit SemVer pre-release publication.
587 ## [2.3.10-2] - 2023-03-18
591 - Fix package.json `exports` syntax for ESM and CommonJS.
593 ## [2.3.10-1] - 2023-03-18
597 - Permit SemVer pre-release publication.
599 ## [2.3.10-0] - 2023-03-18
603 - Fix package.json `exports` syntax for ESM and CommonJS.
605 ## [2.3.9] - 2023-03-18
609 - Introduce ESM module support along with CommonJS one.
613 - Fix brown paper bag bug referencing the same object literal.
615 ## [2.3.8] - 2023-03-18
619 - Switch internal benchmarking code to benny.
620 - Switch to TypeScript 5.x.x.
621 - Switch rollup bundler plugins to core ones.
622 - Switch to TSDoc syntax.
623 - Enforce conventional commits.
627 - Fix random integer generator.
628 - Fix worker choice strategy pool type identification at initialization.
630 ## [2.3.7] - 2022-10-23
634 - Switch to open collective FOSS project funding platform.
635 - Switch to ts-standard linter configuration on TypeScript code.
639 - Fixed missing async on pool execute method.
640 - Fixed typing in TypeScript example.
641 - Fixed types in unit tests.
643 ## [2.3.6] - 2022-10-22
647 - Cleanup pool attributes and methods.
648 - Refine error types thrown.
652 - Fix continuous integration build on windows.
653 - Fix code coverage reporting by using c8 instead of nyc.
655 ## [2.3.5] - 2022-10-21
659 - Improve benchmarks: add IO intensive task workload, add task size option, integrate code into linter.
660 - Optimize tasks usage lookup implementation.
664 - Fix missed pool event emitter type export.
665 - Fix typedoc documentation generation.
667 ## [2.3.4] - 2022-10-17
671 - Fully automate release process with release-it.
675 - Optimize fair share task scheduling algorithm implementation.
676 - Update benchmarks versus external pools results with latest version.
678 ## [2.3.3] - 2022-10-15
682 - Add support for [cluster settings](https://nodejs.org/api/cluster.html#cluster_cluster_settings) in cluster pool options.
684 ## [2.3.2] - 2022-10-14
688 - Optimize fair share worker selection strategy implementation.
692 - Fix WRR worker selection strategy: ensure the condition triggering the round robin can be fulfilled.
694 ## [2.3.1] - 2022-10-13
698 - Pool worker choice strategies:
699 - `WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN` strategy based on weighted round robin scheduling algorithm using tasks execution time for now.
700 - `WorkerChoiceStrategies.FAIR_SHARE` strategy based on fair share scheduling algorithm using tasks execution time for now.
702 ## [2.2.2] - 2022-10-09
706 - Fixed `README.md` file.
708 ## [2.2.1] - 2022-10-08
712 - Dynamic worker choice strategy change at runtime.
714 ## [2.2.0] - 2022-01-05
718 - Support only Node.js version 16.x.x for cluster pool: upstream cluster API have changed on that version.
720 ## [2.1.0] - 2021-08-29
724 - Add an optional pool option `messageHandler` to `PoolOptions<Worker>` for registering a message handler callback on each worker.
728 - `AbstractWorker` class `maxInactiveTime`, `killBehavior` and `async` attributes have been removed in favour of the same ones in the worker options `opts` public attribute.
729 - `AbstractWorker` class `lastTask` attribute have been renamed to `lastTaskTimestamp`.
730 - `AbstractWorker` class `interval` attribute have been renamed to `aliveInterval`.
731 - `AbstractWorker` class cannot be instantiated without specifying the `mainWorker` argument referencing the main worker.
733 ## [2.0.2] - 2021-05-12
737 - Fix `busy` event emission on fixed pool type
739 ## [2.0.1] - 2021-03-16
743 - Check if pool options are properly set.
744 - `busy` event is emitted on all pool types.
746 ## [2.0.0] - 2021-03-01
750 - Now a thread/process by default is not deleted when the task submitted take more time than maxInactiveTime configured (issue #70).
754 - `FullPool` event is now renamed to `busy`.
755 - `maxInactiveTime` on `ThreadWorker` default behavior is now changed, if you want to keep the old behavior set `killBehavior` to `KillBehaviors.HARD`.
756 _Find more details on our JSDoc._
758 - `maxTasks` option on `FixedThreadPool` and `DynamicThreadPool` is now removed since is no more needed.
760 - We changed some internal structures, but you shouldn't be too affected by them as these are internal changes.
762 ### Pool options types declaration merge
764 `FixedThreadPoolOptions` and `DynamicThreadPoolOptions` type declarations have been merged to `PoolOptions<Worker>`.
766 #### New `export` strategy
770 const DynamicThreadPool = require('poolifier/lib/dynamic')
772 const { DynamicThreadPool } = require('poolifier/lib/dynamic')
775 But you should always prefer just using
778 const { DynamicThreadPool } = require('poolifier')
781 #### New type definitions for input data and response
783 For cluster worker and worker-thread pools, you can now only send and receive structured-cloneable data.
784 _This is not a limitation by poolifier but Node.js._
786 #### Public property replacements
788 `numWorkers` property is now `numberOfWorkers`
790 #### Internal (protected) properties and methods renaming
792 These properties are not intended for end users
794 - `id` => `nextMessageId`
796 These methods are not intended for end users
798 - `_chooseWorker` => `chooseWorker`
799 - `_newWorker` => `createWorker`
800 - `_execute` => `internalExecute`
801 - `_chooseWorker` => `chooseWorker`
802 - `_checkAlive` => `checkAlive`
804 - `_runAsync` => `runAsync`
806 ## [1.1.0] - 2020-05-21
810 - ThreadWorker support async functions as option
811 - Various external library patches
813 ## [1.0.0] - 2020-01-24
817 - FixedThreadPool implementation
818 - DynamicThreadPool implementation
819 - WorkerThread implementation to improve developer experience