happy-ferret / worker-threads-pool

Easily manage a pool of Node.js Worker Threads

worker-threads-pool

Easily manage a pool of Node.js Worker Threads.

Installation

npm install worker-threads-pool --save

Prerequisites

Worker Threads in Node.js are still an experimental feature and is only supported in Node.js v10.5.0 and above. To use Worker Threads, you need to run node with the --experimental-worker flag:

node --experimental-worker app.js

Usage

const Pool = require('worker-threads-pool')

const pool = new Pool({max: 5})

for (let i = 0; i < 100; i++) {
  pool.acquire('/my/worker.js', {}, function (worker) {
    console.log(`started worker ${i} (pool size: ${pool.size})`)
    worker.on('exit', function () {
      console.log(`worker ${i} exited (pool size: ${pool.size})`)
    })
  })
}

API

pool = new Pool([options])

options is an optional object/dictionary with the any of the following properties:

• max - Maximum number of workers allowed in the pool. Other workers will be queued and started once there's room in the pool (default: 1)

pool.size

Number of active workers in the pool.

pool.acquire(filename, options, callback)

The filename and options arguments are passed directly to new Worker(filename, options).

The callback argument will be called with the worker once it's created.

pool.destroy([callback])

Calls worker.terminate() on all workers in the pool.

Will call the optional callback once all workers have terminated.

License

MIT