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

   1 import type { IPoolWorker } from '../pool-worker'
   2 import { AbstractWorkerChoiceStrategy } from './abstract-worker-choice-strategy'
   3 import type {
   4   IWorkerChoiceStrategy,
   5   RequiredStatistics
   6 } from './selection-strategies-types'
   7
   8 /**
   9  * Selects the less busy worker.
  10  *
  11  * @typeParam Worker - Type of worker which manages the strategy.
  12  * @typeParam Data - Type of data sent to the worker. This can only be serializable data.
  13  * @typeParam Response - Type of response of execution. This can only be serializable data.
  14  */
  15 export class LessBusyWorkerChoiceStrategy<
  16     Worker extends IPoolWorker,
  17     Data,
  18     Response
  19   >
  20   extends AbstractWorkerChoiceStrategy<Worker, Data, Response>
  21   implements IWorkerChoiceStrategy {
  22   /** {@inheritDoc} */
  23   public readonly requiredStatistics: RequiredStatistics = {
  24     runTime: true
  25   }
  26
  27   /** {@inheritDoc} */
  28   public reset (): boolean {
  29     return true
  30   }
  31
  32   /** {@inheritDoc} */
  33   public choose (): number {
  34     const freeWorkerKey = this.pool.findFreeWorkerKey()
  35     if (!this.isDynamicPool && freeWorkerKey !== -1) {
  36       return freeWorkerKey
  37     }
  38     let minRunTime = Infinity
  39     let lessBusyWorkerKey!: number
  40     for (const [index, workerItem] of this.pool.workers.entries()) {
  41       const workerRunTime = workerItem.tasksUsage.runTime
  42       if (workerRunTime === 0) {
  43         return index
  44       } else if (workerRunTime < minRunTime) {
  45         minRunTime = workerRunTime
  46         lessBusyWorkerKey = index
  47       }
  48     }
  49     return lessBusyWorkerKey
  50   }
  51
  52   /** {@inheritDoc} */
  53   public remove (workerKey: number): boolean {
  54     return true
  55   }
  56 }