src/pools/selection-strategies/least-elu-worker-choice-strategy.ts

   1 import type { IPool } from '../pool.js'
   2 import type { IWorker } from '../worker.js'
   3 import type {
   4   IWorkerChoiceStrategy,
   5   TaskStatisticsRequirements,
   6   WorkerChoiceStrategyOptions,
   7 } from './selection-strategies-types.js'
   8
   9 import { DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS } from '../utils.js'
  10 import { AbstractWorkerChoiceStrategy } from './abstract-worker-choice-strategy.js'
  11
  12 /**
  13  * Selects the worker with the least ELU.
  14  * @typeParam Worker - Type of worker which manages the strategy.
  15  * @typeParam Data - Type of data sent to the worker. This can only be structured-cloneable data.
  16  * @typeParam Response - Type of execution response. This can only be structured-cloneable data.
  17  */
  18 export class LeastEluWorkerChoiceStrategy<
  19     Worker extends IWorker,
  20     Data = unknown,
  21     Response = unknown
  22   >
  23   extends AbstractWorkerChoiceStrategy<Worker, Data, Response>
  24   implements IWorkerChoiceStrategy {
  25   /** @inheritDoc */
  26   public override readonly taskStatisticsRequirements: TaskStatisticsRequirements =
  27     {
  28       elu: {
  29         aggregate: true,
  30         average: false,
  31         median: false,
  32       },
  33       runTime: DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS,
  34       waitTime: DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS,
  35     }
  36
  37   /** @inheritDoc */
  38   public constructor (
  39     pool: IPool<Worker, Data, Response>,
  40     opts?: WorkerChoiceStrategyOptions
  41   ) {
  42     super(pool, opts)
  43     this.setTaskStatisticsRequirements(this.opts)
  44   }
  45
  46   private leastEluNextWorkerNodeKey (): number | undefined {
  47     return this.pool.workerNodes.reduce(
  48       (minWorkerNodeKey, workerNode, workerNodeKey, workerNodes) => {
  49         return this.isWorkerNodeReady(workerNodeKey) &&
  50           (workerNode.usage.elu.active.aggregate ?? 0) <
  51             (workerNodes[minWorkerNodeKey].usage.elu.active.aggregate ?? 0)
  52           ? workerNodeKey
  53           : minWorkerNodeKey
  54       },
  55       0
  56     )
  57   }
  58
  59   /** @inheritDoc */
  60   public choose (): number | undefined {
  61     this.setPreviousWorkerNodeKey(this.nextWorkerNodeKey)
  62     this.nextWorkerNodeKey = this.leastEluNextWorkerNodeKey()
  63     return this.nextWorkerNodeKey
  64   }
  65
  66   /** @inheritDoc */
  67   public remove (): boolean {
  68     return true
  69   }
  70
  71   /** @inheritDoc */
  72   public reset (): boolean {
  73     return true
  74   }
  75
  76   /** @inheritDoc */
  77   public update (): boolean {
  78     return true
  79   }
  80 }