src/pools/selection-strategies/less-recently-used-worker-choice-strategy.ts

   1 import type { AbstractPoolWorker } from '../abstract-pool-worker'
   2 import { AbstractWorkerChoiceStrategy } from './abstract-worker-choice-strategy'
   3
   4 /**
   5  * Selects the less recently used worker.
   6  *
   7  * @template Worker Type of worker which manages the strategy.
   8  * @template Data Type of data sent to the worker. This can only be serializable data.
   9  * @template Response Type of response of execution. This can only be serializable data.
  10  */
  11 export class LessRecentlyUsedWorkerChoiceStrategy<
  12   Worker extends AbstractPoolWorker,
  13   Data,
  14   Response
  15 > extends AbstractWorkerChoiceStrategy<Worker, Data, Response> {
  16   /** @inheritdoc */
  17   public choose (): Worker {
  18     let minNumberOfRunningTasks = Infinity
  19     // A worker is always found because it picks the one with fewer tasks
  20     let lessRecentlyUsedWorker!: Worker
  21     for (const worker of this.pool.workers) {
  22       const workerRunningTasks = this.pool.getWorkerRunningTasks(worker)
  23       if (!this.isDynamicPool && workerRunningTasks === 0) {
  24         return worker
  25       } else if (
  26         workerRunningTasks !== undefined &&
  27         workerRunningTasks < minNumberOfRunningTasks
  28       ) {
  29         lessRecentlyUsedWorker = worker
  30         minNumberOfRunningTasks = workerRunningTasks
  31       }
  32     }
  33     return lessRecentlyUsedWorker
  34   }
  35 }