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