Easily manage a pool of Node.js Worker Threads.
npm install worker-threads-pool --save
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
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 (err, worker) {
if (err) throw err
console.log(`started worker ${i} (pool size: ${pool.size})`)
worker.on('exit', function () {
console.log(`worker ${i} exited (pool size: ${pool.size})`)
})
})
}
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
)maxWaiting
- Maximum number of workers waiting to be started when
the pool is full. The callback to pool.acquire
will be called with
an error in case this limit is reachedpool.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 an optional error object
and 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.