2 <img src="./images/logo.png" width="340px" height="266px"/>
7 # Node.js Worker_Threads and Cluster Worker Pool
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28 Poolifier is used to perform CPU and/or I/O intensive tasks on Node.js servers, it implements worker pools using [worker_threads](https://nodejs.org/api/worker_threads.html) and [cluster](https://nodejs.org/api/cluster.html) Node.js modules.
29 With poolifier you can improve your **performance** and resolve problems related to the event loop.
30 Moreover you can execute your tasks using an API designed to improve the **developer experience**.
31 Please consult our [general guidelines](#general-guidelines).
33 - Easy to use :white_check_mark:
34 - Fixed and dynamic pool size :white_check_mark:
35 - Easy switch from a pool type to another :white_check_mark:
36 - Performance [benchmarks](./benchmarks/README.md) :white_check_mark:
37 - No runtime dependencies :white_check_mark:
38 - Proper integration with Node.js [async_hooks](https://nodejs.org/api/async_hooks.html) :white_check_mark:
39 - Support for CommonJS, ESM and TypeScript :white_check_mark:
40 - Support for [worker_threads](https://nodejs.org/api/worker_threads.html) and [cluster](https://nodejs.org/api/cluster.html) Node.js modules :white_check_mark:
41 - Support for multiple task functions :white_check_mark:
42 - Support for task functions [CRUD](https://en.wikipedia.org/wiki/Create,_read,_update_and_delete) operations at runtime :white_check_mark:
43 - Support for sync and async task functions :white_check_mark:
44 - Tasks distribution strategies :white_check_mark:
45 - Lockless tasks queueing :white_check_mark:
46 - Queued tasks rescheduling:
47 - Task stealing on idle :white_check_mark:
48 - Tasks stealing under back pressure :white_check_mark:
49 - Tasks redistribution on worker error :white_check_mark:
50 - General guidelines on pool choice :white_check_mark:
51 - Error handling out of the box :white_check_mark:
52 - Widely tested :white_check_mark:
53 - Active community :white_check_mark:
54 - Code quality [![Bugs](https://sonarcloud.io/api/project_badges/measure?project=poolifier_poolifier&metric=bugs)](https://sonarcloud.io/dashboard?id=poolifier_poolifier)
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60 - Code security [![Security Rating](https://sonarcloud.io/api/project_badges/measure?project=poolifier_poolifier&metric=security_rating)](https://sonarcloud.io/dashboard?id=poolifier_poolifier) [![Vulnerabilities](https://sonarcloud.io/api/project_badges/measure?project=poolifier_poolifier&metric=vulnerabilities)](https://sonarcloud.io/dashboard?id=poolifier_poolifier)
64 - [Overview](#overview)
65 - [Installation](#installation)
67 - [Node.js versions](#nodejs-versions)
69 - [General guidelines](#general-guidelines)
70 - [Worker choice strategies](#worker-choice-strategies)
71 - [Contribute](#contribute)
77 Poolifier contains two [worker_threads](https://nodejs.org/api/worker_threads.html#class-worker)/[cluster](https://nodejs.org/api/cluster.html#cluster_class_worker) worker pool implementations, you don't have to deal with [worker_threads](https://nodejs.org/api/worker_threads.html)/[cluster](https://nodejs.org/api/cluster.html) complexity.
78 The first implementation is a fixed worker pool, with a defined number of workers that are started at creation time and will be reused.
79 The second implementation is a dynamic worker pool, with a number of worker started at creation time (these workers will be always active and reused) and other workers created when the load will increase (with an upper limit, these workers will be reused when active), the newly created workers will be stopped after a configurable period of inactivity.
80 You have to implement your worker by extending the _ThreadWorker_ or _ClusterWorker_ class.
85 npm install poolifier --save
90 You can implement a [worker_threads](https://nodejs.org/api/worker_threads.html#class-worker) worker in a simple way by extending the class _ThreadWorker_:
93 import { ThreadWorker } from 'poolifier'
95 function yourFunction(data) {
96 // this will be executed in the worker thread,
97 // the data will be received by using the execute method
101 module.exports = new ThreadWorker(yourFunction, {
102 maxInactiveTime: 60000
106 Instantiate your pool based on your needs :
109 import { DynamicThreadPool, FixedThreadPool, PoolEvents, availableParallelism } from 'poolifier'
111 // a fixed worker_threads pool
112 const pool = new FixedThreadPool(availableParallelism(), './yourWorker.js', {
113 errorHandler: (e) => console.error(e),
114 onlineHandler: () => console.info('worker is online')
117 pool.emitter?.on(PoolEvents.ready, () => console.info('Pool is ready'))
118 pool.emitter?.on(PoolEvents.busy, () => console.info('Pool is busy'))
120 // or a dynamic worker_threads pool
121 const pool = new DynamicThreadPool(Math.floor(availableParallelism() / 2), availableParallelism(), './yourWorker.js', {
122 errorHandler: (e) => console.error(e),
123 onlineHandler: () => console.info('worker is online')
126 pool.emitter?.on(PoolEvents.full, () => console.info('Pool is full'))
127 pool.emitter?.on(PoolEvents.ready, () => console.info('Pool is ready'))
128 pool.emitter?.on(PoolEvents.busy, () => console.info('Pool is busy'))
130 // the execute method signature is the same for both implementations,
131 // so you can easily switch from one to another
142 You can do the same with the classes _ClusterWorker_, _FixedClusterPool_ and _DynamicClusterPool_.
144 **See [examples](./examples/) for more details**:
146 - [Javascript](./examples/javascript/)
147 - [Typescript](./examples/typescript/)
148 - [HTTP client pool](./examples/typescript/http-client-pool/)
149 - [SMTP client pool](./examples/typescript/smtp-client-pool/)
150 - [HTTP server pool](./examples/typescript/http-server-pool/)
151 - [Express worker_threads pool](./examples/typescript/http-server-pool/express-worker_threads/)
152 - [Express cluster pool](./examples/typescript/http-server-pool/express-cluster/)
153 - [Express hybrid pool](./examples/typescript/http-server-pool/express-hybrid/)
154 - [Fastify worker_threads pool](./examples/typescript/http-server-pool/fastify-worker_threads/)
155 - [Fastify cluster pool](./examples/typescript/http-server-pool/fastify-cluster/)
156 - [Fastify hybrid pool](./examples/typescript/http-server-pool/fastify-hybrid/)
157 - [WebSocket server pool](./examples/typescript/websocket-server-pool/)
158 - [ws worker_threads pool](./examples/typescript/websocket-server-pool/ws-worker_threads/)
159 - [ws cluster pool](./examples/typescript/websocket-server-pool/ws-cluster/)
160 - [ws hybrid pool](./examples/typescript/websocket-server-pool/ws-hybrid/)
162 Remember that workers can only send and receive structured-cloneable data.
166 Node.js versions >= 18.x.x are supported.
168 ## [API](./docs/api.md)
170 ## [General guidelines](./docs/general-guidelines.md)
172 ## [Worker choice strategies](./docs/worker-choice-strategies.md)
176 Choose your task [here](https://github.com/orgs/poolifier/projects/1), propose an idea, a fix, an improvement.
178 See [CONTRIBUTING](./CONTRIBUTING.md) guidelines.
184 - [**Alessandro Pio Ardizio**](https://github.com/pioardi)
188 - [**Jérôme Benoit**](https://github.com/jerome-benoit)
192 - [**Shinigami92**](https://github.com/Shinigami92)