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 ## [2.6.35] - 2023-08-25
14 - Don't account worker usage statistics for tasks that have failed.
15 - Fix pool information runtime and wait time median computation.
19 - Update simple moving average implementation to use a circular buffer.
20 - Update simple moving median implementation to use a circular buffer.
21 - Account for stolen tasks in worker usage statistics and pool information.
25 - Continuous tasks stealing algorithm.
27 ## [2.6.34] - 2023-08-24
31 - Avoid cascading tasks stealing under back pressure.
35 - Add fastpath to queued tasks rescheduling.
37 ## [2.6.33] - 2023-08-24
41 - Fix queued tasks rescheduling.
45 - Rename tasks queue options `queueMaxSize` to `size`.
49 - Task stealing scheduling algorithm if tasks queueing is enabled.
51 ## [2.6.32] - 2023-08-23
55 - Ensure no task can be executed when the pool is destroyed.
59 - Add `queueMaxSize` option to tasks queue options.
60 - Add O(1) deque implementation implemented with doubly linked list and use it for tasks queueing.
61 - Add tasks stealing algorithm when a worker node queue is back pressured if tasks queueing is enabled.
63 ## [2.6.31] - 2023-08-20
67 - Fix worker choice strategy retries mechanism in some edge cases.
71 - Make orthogonal worker choice strategies tasks distribution and created dynamic worker usage.
72 - Remove the experimental status of the `LEAST_ELU` worker choice strategy.
74 ## [2.6.30] - 2023-08-19
78 - Ensure pool event `backPressure` is emitted.
79 - Ensure pool event `full` is emitted only once.
80 - Ensure worker node cannot be instantiated without proper arguments.
82 ## [2.6.29] - 2023-08-18
86 - Fix race condition between ready and task functions worker message handling at startup.
87 - Fix duplicate task function worker usage statistics computation per task function.
88 - Update task function worker usage statistics if and only if there's at least two different task functions.
89 - Fix race condition at task function worker usage executing task computation leading to negative value.
93 - 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).
94 - Use back pressure detection in worker choice strategies.
95 - Add worker choice strategies retries mechanism if no worker is eligible.
97 ## [2.6.28] - 2023-08-16
101 - Ensure pool workers are properly initialized.
105 - HTTP server pool examples: express-cluster, express-hybrid.
109 - Remove now useless branching in worker hot code path.
111 ## [2.6.27] - 2023-08-15
115 - Add `KillHandler` type definition to exported types.
119 - Add `destroy` event to pool API.
121 ## [2.6.26] - 2023-08-15
125 - Add kill handler to worker options allowing to execute custom code when worker is killed.
126 - Add `listTaskFunctions()` method to pool API.
127 - SMTP server pool example: nodemailer.
129 ## [2.6.25] - 2023-08-13
133 - HTTP server pool examples: fastify-cluster, fastify-hybrid.
134 - WebSocket server pool examples: ws-cluster, ws-hybrid.
136 ## [2.6.24] - 2023-08-12
140 - Add array of transferable objects to the `execute()` method arguments.
141 - WebSocket server pool examples: ws-worker_threads.
143 ## [2.6.23] - 2023-08-11
147 - 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.
151 - HTTP client pool examples: fetch, node-fetch and axios with multiple task functions.
152 - HTTP server pool examples: express-worker_threads, fastify-worker_threads.
154 ## [2.6.22] - 2023-08-10
158 - Add missing `types` field to package.json `exports`.
162 - Structure markdown documentation (PR #811).
164 ## [2.6.21] - 2023-08-03
168 - Improve code documentation.
169 - Code refactoring and cleanup for better maintainability and readability.
171 ## [2.6.20] - 2023-07-21
175 - Fix queued tasks redistribution on error task execution starvation.
176 - Ensure tasks queueing per worker condition is untangled from the pool busyness semantic.
180 - Drastically reduce lookups by worker in the worker nodes.
182 ## [2.6.19] - 2023-07-20
186 - Dedicated internal communication channel for worker_threads pools.
188 ## [2.6.18] - 2023-07-19
192 - Code refactoring and cleanup for better maintainability and readability. Bundle size is a bit smaller.
194 ## [2.6.17] - 2023-07-16
198 - Add `listTaskFunctions()` method to worker API.
200 ## [2.6.16] - 2023-07-12
204 - Fix pool startup detection.
205 - Fix worker task functions handling.
207 ## [2.6.15] - 2023-07-11
211 - Take into account worker node readiness in worker choice strategies.
213 ## [2.6.14] - 2023-07-10
217 - Fix task function statistics tracking.
219 ## [2.6.13] - 2023-07-10
223 - Add per task function statistics tracking.
224 - Add public methods to manipulate the worker task functions at runtime.
226 ## [2.6.12] - 2023-07-09
230 - Workaround import issue with `node:os` module in node 16.x.x.
232 ## [2.6.11] - 2023-07-09
236 - Fix pool readiness semantic.
238 ## [2.6.10] - 2023-07-08
242 - Ensure workers are not recreated on error at pool startup.
246 - Add `ready` and `strategy` fields to pool information.
247 - Add pool event `ready` to notify when the number of workers created in the pool has reached the maximum size expected and are ready.
248 - Add dynamic pool sizing checks.
250 ## [2.6.9] - 2023-07-07
254 - Recreate the right worker type on uncaught exception.
258 - Add minimum and maximum to internal measurement statistics.
259 - Add `runTime` and `waitTime` to pool information.
260 - Check worker inactive time only on dynamic worker.
262 ## [2.6.8] - 2023-07-03
266 - Brown paper bag release to fix version handling in pool information.
268 ## [2.6.7] - 2023-07-03
272 - Ensure worker queued tasks at error are reassigned to other pool workers.
276 - Add pool `utilization` ratio to pool information.
277 - Add `version` to pool information.
278 - Add worker information to worker nodes.
280 ## [2.6.6] - 2023-07-01
284 - Add safe helper `availableParallelism()` to help sizing the pool.
288 - Ensure message handler is only registered in worker.
290 ## [2.6.5] - 2023-06-27
294 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
298 - Artificial version bump to 2.6.5 to workaround publication issue.
299 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
300 - Ensure pool event is emitted before task error promise rejection.
301 - Fix queued tasks count computation.
305 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
307 ## [2.6.4] - 2023-06-27
311 - Cluster pools tasks execution are not working by using ESM files extension: https://github.com/poolifier/poolifier/issues/782
315 - Ensure cluster pool `destroy()` gracefully shutdowns worker's server.
316 - Ensure pool event is emitted before task error promise rejection.
317 - Fix queued tasks count computation.
321 - Remove unneeded worker_threads worker `MessageChannel` internal usage for IPC.
323 ## [2.6.3] - 2023-06-19
327 - Ensure no tasks are queued when trying to soft kill a dynamic worker.
328 - Update strategies internals after statistics computation.
332 - Optimize O(1) queue implementation.
334 ## [2.6.2] - 2023-06-12
338 - Fix new worker use after creation in dynamic pool given the current worker choice strategy.
340 ## [2.6.1] - 2023-06-10
344 - Add worker choice strategy documentation: [README.md](./docs/worker-choice-strategies.md).
348 - Fix average statistics computation: ensure failed tasks are not accounted.
350 ## [2.6.0] - 2023-06-09
354 - Add `LEAST_ELU` worker choice strategy (experimental).
355 - Add tasks ELU instead of runtime support to `FAIR_SHARE` worker choice strategy.
359 - Refactor pool worker node usage internals.
360 - Breaking change: refactor worker choice strategy statistics requirements: the syntax of the worker choice strategy options has changed.
361 - Breaking change: pool information `info` property object fields have been renamed.
365 - Fix wait time accounting.
366 - Ensure worker choice strategy `LEAST_BUSY` accounts also tasks wait time.
367 - Ensure worker choice strategy `LEAST_USED` accounts also queued tasks.
369 ## [2.5.4] - 2023-06-07
373 - Add Event Loop Utilization (ELU) statistics to worker tasks usage.
377 - Compute statistics at the worker level only if needed.
378 - Add `worker_threads` options to thread pool options.
382 - Make the `LEAST_BUSY` strategy only relies on task runtime.
384 ## [2.5.3] - 2023-06-04
388 - Refine pool information content.
389 - Limit pool internals public exposure.
391 ## [2.5.2] - 2023-06-02
395 - Add `taskError` pool event for task execution error.
396 - Add pool information `info` property to pool.
397 - Emit pool information on `busy` and `full` pool events.
399 ## [2.5.1] - 2023-06-01
403 - Add pool option `restartWorkerOnError` to restart worker on uncaught error. Default to `true`.
404 - Add `error` pool event for uncaught worker error.
406 ## [2.5.0] - 2023-05-31
410 - Switch pool event emitter to `EventEmitterAsyncResource`.
411 - Add tasks wait time accounting in per worker tasks usage.
412 - Add interleaved weighted round robin `INTERLEAVED_WEIGHTED_ROUND_ROBIN` worker choice strategy (experimental).
416 - Renamed worker choice strategy `LESS_BUSY` to `LEAST_BUSY` and `LESS_USED` to `LEAST_USED`.
418 ## [2.4.14] - 2023-05-09
422 - Ensure no undefined task runtime can land in the tasks history.
423 - Fix median computation implementation once again.
427 - Unit tests for median and queue implementations.
429 ## [2.4.13] - 2023-05-08
433 - Fix worker choice strategy options validation.
434 - Fix fair share worker choice strategy internals update: ensure virtual task end timestamp is computed at task submission.
436 ## [2.4.12] - 2023-05-06
440 - Support multiple task functions per worker.
441 - Add custom worker weights support to worker choice strategies options.
445 - Use O(1) queue implementation for tasks queueing.
449 - Fix median computation implementation.
450 - Fix fair share worker choice strategy internals update.
452 ## [2.4.11] - 2023-04-23
456 - Optimize free worker finding in worker choice strategies.
458 ## [2.4.10] - 2023-04-15
462 - Fix typescript type definition for task function: ensure the input data is optional.
463 - Fix typescript type definition for pool execute(): ensure the input data is optional.
465 ## [2.4.9] - 2023-04-15
469 - Add tasks queue enablement runtime setter to pool.
470 - Add tasks queue options runtime setter to pool.
471 - Add worker choice strategy options runtime setter to pool.
475 - Remove the tasks queuing experimental status.
479 - Fix task function type definition and validation.
480 - Fix worker choice strategy options handling.
482 ## [2.4.8] - 2023-04-12
486 - Fix message between main worker and worker type definition for tasks.
487 - Fix code documentation.
489 ## [2.4.7] - 2023-04-11
493 - Add worker tasks queue options to pool options.
497 - Fix missing documentation.
499 ## [2.4.6] - 2023-04-10
503 - Ensure one task at a time is executed per worker with tasks queueing enabled.
504 - Properly count worker executing tasks with tasks queueing enabled.
506 ## [2.4.5] - 2023-04-09
510 - Use monotonic high resolution timer for worker tasks runtime.
511 - Add worker tasks median runtime to statistics.
512 - Add worker tasks queue (experimental).
514 ## [2.4.4] - 2023-04-07
518 - Add `PoolEvents` enumeration and `PoolEvent` type.
522 - Destroy worker only on alive check.
524 ## [2.4.3] - 2023-04-07
528 - Fix typedoc generation with inheritance.
530 ## [2.4.2] - 2023-04-06
534 - Add `full` event to dynamic pool.
535 - Keep worker choice strategy in memory for conditional reuse.
539 - Fix possible negative worker key at worker removal in worker choice strategies.
541 ## [2.4.1] - 2023-04-05
545 - Optimize worker choice strategy for dynamic pool.
549 - Ensure dynamic pool does not alter worker choice strategy expected behavior.
551 ## [2.4.0] - 2023-04-04
555 - Add `LESS_BUSY` worker choice strategy.
559 - Optimize worker storage in pool.
560 - Optimize worker alive status check.
561 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
562 - Optimize `LESS_USED` worker choice strategy.
563 - Update benchmarks versus external threads pools.
564 - Optimize tasks usage statistics requirements for 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 ## [2.4.0-3] - 2023-04-04
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.
585 - Update benchmarks versus external threads pools.
589 - Ensure trimmable characters are checked at pool initialization.
590 - Fix message id integer overflow.
591 - Fix pool worker removal in worker choice strategy internals.
592 - Fix package publication with pnpm.
594 ## [2.4.0-2] - 2023-04-03
598 - Add `LESS_BUSY` worker choice strategy.
602 - Optimize worker storage in pool.
603 - Optimize worker alive status check.
604 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
605 - Optimize `LESS_USED` worker choice strategy.
609 - Ensure trimmable characters are checked at pool initialization.
610 - Fix message id integer overflow.
611 - Fix pool worker removal in worker choice strategy internals.
612 - Fix package publication with pnpm.
614 ## [2.4.0-1] - 2023-04-03
618 - Add `LESS_BUSY` worker choice strategy.
622 - Optimize worker storage in pool.
623 - Optimize worker alive status check.
624 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
625 - Optimize `LESS_USED` worker choice strategy.
629 - Ensure trimmable characters are checked at pool initialization.
630 - Fix message id integer overflow.
631 - Fix pool worker removal in worker choice strategy internals.
633 ## [2.4.0-0] - 2023-04-03
637 - Add `LESS_BUSY` worker choice strategy.
641 - Optimize worker storage in pool.
642 - Optimize worker alive status check.
643 - BREAKING CHANGE: Rename worker choice strategy `LESS_RECENTLY_USED` to `LESS_USED`.
644 - Optimize `LESS_USED` worker choice strategy.
648 - Ensure trimmable characters are checked at pool initialization.
649 - Fix message id integer overflow.
650 - Fix pool worker removal in worker choice strategy internals.
652 ## [2.3.10] - 2023-03-18
656 - Fix package.json `exports` syntax for ESM and CommonJS.
660 - Permit SemVer pre-release publication.
662 ## [2.3.10-2] - 2023-03-18
666 - Fix package.json `exports` syntax for ESM and CommonJS.
668 ## [2.3.10-1] - 2023-03-18
672 - Permit SemVer pre-release publication.
674 ## [2.3.10-0] - 2023-03-18
678 - Fix package.json `exports` syntax for ESM and CommonJS.
680 ## [2.3.9] - 2023-03-18
684 - Introduce ESM module support along with CommonJS one.
688 - Fix brown paper bag bug referencing the same object literal.
690 ## [2.3.8] - 2023-03-18
694 - Switch internal benchmarking code to benny.
695 - Switch to TypeScript 5.x.x.
696 - Switch rollup bundler plugins to core ones.
697 - Switch to TSDoc syntax.
698 - Enforce conventional commits.
702 - Fix random integer generator.
703 - Fix worker choice strategy pool type identification at initialization.
705 ## [2.3.7] - 2022-10-23
709 - Switch to open collective FOSS project funding platform.
710 - Switch to ts-standard linter configuration on TypeScript code.
714 - Fixed missing async on pool execute method.
715 - Fixed typing in TypeScript example.
716 - Fixed types in unit tests.
718 ## [2.3.6] - 2022-10-22
722 - Cleanup pool attributes and methods.
723 - Refine error types thrown.
727 - Fix continuous integration build on windows.
728 - Fix code coverage reporting by using c8 instead of nyc.
730 ## [2.3.5] - 2022-10-21
734 - Improve benchmarks: add IO intensive task workload, add task size option, integrate code into linter.
735 - Optimize tasks usage lookup implementation.
739 - Fix missed pool event emitter type export.
740 - Fix typedoc documentation generation.
742 ## [2.3.4] - 2022-10-17
746 - Fully automate release process with release-it.
750 - Optimize fair share task scheduling algorithm implementation.
751 - Update benchmarks versus external pools results with latest version.
753 ## [2.3.3] - 2022-10-15
757 - Add support for [cluster settings](https://nodejs.org/api/cluster.html#cluster_cluster_settings) in cluster pool options.
759 ## [2.3.2] - 2022-10-14
763 - Optimize fair share worker selection strategy implementation.
767 - Fix WRR worker selection strategy: ensure the condition triggering the round robin can be fulfilled.
769 ## [2.3.1] - 2022-10-13
773 - Pool worker choice strategies:
774 - `WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN` strategy based on weighted round robin scheduling algorithm using tasks execution time for now.
775 - `WorkerChoiceStrategies.FAIR_SHARE` strategy based on fair share scheduling algorithm using tasks execution time for now.
777 ## [2.2.2] - 2022-10-09
781 - Fixed `README.md` file.
783 ## [2.2.1] - 2022-10-08
787 - Dynamic worker choice strategy change at runtime.
789 ## [2.2.0] - 2022-01-05
793 - Support only Node.js version 16.x.x for cluster pool: upstream cluster API have changed on that version.
795 ## [2.1.0] - 2021-08-29
799 - Add an optional pool option `messageHandler` to `PoolOptions<Worker>` for registering a message handler callback on each worker.
803 - `AbstractWorker` class `maxInactiveTime`, `killBehavior` and `async` attributes have been removed in favour of the same ones in the worker options `opts` public attribute.
804 - `AbstractWorker` class `lastTask` attribute have been renamed to `lastTaskTimestamp`.
805 - `AbstractWorker` class `interval` attribute have been renamed to `aliveInterval`.
806 - `AbstractWorker` class cannot be instantiated without specifying the `mainWorker` argument referencing the main worker.
808 ## [2.0.2] - 2021-05-12
812 - Fix `busy` event emission on fixed pool type
814 ## [2.0.1] - 2021-03-16
818 - Check if pool options are properly set.
819 - `busy` event is emitted on all pool types.
821 ## [2.0.0] - 2021-03-01
825 - Now a thread/process by default is not deleted when the task submitted take more time than maxInactiveTime configured (issue #70).
829 - `FullPool` event is now renamed to `busy`.
830 - `maxInactiveTime` on `ThreadWorker` default behavior is now changed, if you want to keep the old behavior set `killBehavior` to `KillBehaviors.HARD`.
831 _Find more details on our JSDoc._
833 - `maxTasks` option on `FixedThreadPool` and `DynamicThreadPool` is now removed since is no more needed.
835 - We changed some internal structures, but you shouldn't be too affected by them as these are internal changes.
837 ### Pool options types declaration merge
839 `FixedThreadPoolOptions` and `DynamicThreadPoolOptions` type declarations have been merged to `PoolOptions<Worker>`.
841 #### New `export` strategy
845 const DynamicThreadPool = require('poolifier/lib/dynamic')
847 const { DynamicThreadPool } = require('poolifier/lib/dynamic')
850 But you should always prefer just using
853 const { DynamicThreadPool } = require('poolifier')
856 #### New type definitions for input data and response
858 For cluster worker and worker-thread pools, you can now only send and receive structured-cloneable data.
859 _This is not a limitation by poolifier but Node.js._
861 #### Public property replacements
863 `numWorkers` property is now `numberOfWorkers`
865 #### Internal (protected) properties and methods renaming
867 These properties are not intended for end users
869 - `id` => `nextMessageId`
871 These methods are not intended for end users
873 - `_chooseWorker` => `chooseWorker`
874 - `_newWorker` => `createWorker`
875 - `_execute` => `internalExecute`
876 - `_chooseWorker` => `chooseWorker`
877 - `_checkAlive` => `checkAlive`
879 - `_runAsync` => `runAsync`
881 ## [1.1.0] - 2020-05-21
885 - ThreadWorker support async functions as option
886 - Various external library patches
888 ## [1.0.0] - 2020-01-24
892 - FixedThreadPool implementation
893 - DynamicThreadPool implementation
894 - WorkerThread implementation to improve developer experience