- /**
- * Choose a worker for the next task.
- *
- * It will first check for and return an idle worker.
- * If all workers are busy, then it will try to create a new one up to the `max` worker count.
- * If the max worker count is reached, the emitter will emit a `FullPool` event and it will fall back to using a round robin algorithm to distribute the load.
- *
- * @returns Cluster worker.
- */
- protected chooseWorker (): Worker {
- let worker: Worker | undefined
- for (const entry of this.tasks) {
- if (entry[1] === 0) {
- worker = entry[0]
- break
- }
- }
-
- if (worker) {
- // A worker is free, use it
- return worker
- } else {
- if (this.workers.length === this.max) {
- this.emitter.emit('FullPool')
- return super.chooseWorker()
- }
- // All workers are busy, create a new worker
- const worker = this.createAndSetupWorker()
- worker.on('message', (message: MessageValue<Data>) => {
- if (message.kill) {
- this.sendToWorker(worker, { kill: 1 })
- void this.destroyWorker(worker)
- }
- })
- return worker
- }