| 1 | import { DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS } from '../../utils' |
| 2 | import type { IPool } from '../pool' |
| 3 | import type { IWorker } from '../worker' |
| 4 | import type { |
| 5 | IWorkerChoiceStrategy, |
| 6 | RequiredStatistics, |
| 7 | WorkerChoiceStrategyOptions |
| 8 | } from './selection-strategies-types' |
| 9 | |
| 10 | /** |
| 11 | * Worker choice strategy abstract base class. |
| 12 | * |
| 13 | * @typeParam Worker - Type of worker which manages the strategy. |
| 14 | * @typeParam Data - Type of data sent to the worker. This can only be serializable data. |
| 15 | * @typeParam Response - Type of execution response. This can only be serializable data. |
| 16 | */ |
| 17 | export abstract class AbstractWorkerChoiceStrategy< |
| 18 | Worker extends IWorker, |
| 19 | Data = unknown, |
| 20 | Response = unknown |
| 21 | > implements IWorkerChoiceStrategy { |
| 22 | /** |
| 23 | * Toggles finding the last free worker node key. |
| 24 | */ |
| 25 | private toggleFindLastFreeWorkerNodeKey: boolean = false |
| 26 | /** @inheritDoc */ |
| 27 | public readonly requiredStatistics: RequiredStatistics = { |
| 28 | runTime: false, |
| 29 | avgRunTime: false, |
| 30 | medRunTime: false, |
| 31 | waitTime: false, |
| 32 | avgWaitTime: false, |
| 33 | medWaitTime: false |
| 34 | } |
| 35 | |
| 36 | /** |
| 37 | * Constructs a worker choice strategy bound to the pool. |
| 38 | * |
| 39 | * @param pool - The pool instance. |
| 40 | * @param opts - The worker choice strategy options. |
| 41 | */ |
| 42 | public constructor ( |
| 43 | protected readonly pool: IPool<Worker, Data, Response>, |
| 44 | protected opts: WorkerChoiceStrategyOptions = DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS |
| 45 | ) { |
| 46 | this.choose = this.choose.bind(this) |
| 47 | } |
| 48 | |
| 49 | protected setRequiredStatistics (opts: WorkerChoiceStrategyOptions): void { |
| 50 | if (this.requiredStatistics.avgRunTime && opts.medRunTime === true) { |
| 51 | this.requiredStatistics.avgRunTime = false |
| 52 | this.requiredStatistics.medRunTime = opts.medRunTime as boolean |
| 53 | } |
| 54 | if (this.requiredStatistics.medRunTime && opts.medRunTime === false) { |
| 55 | this.requiredStatistics.avgRunTime = true |
| 56 | this.requiredStatistics.medRunTime = opts.medRunTime as boolean |
| 57 | } |
| 58 | if (this.requiredStatistics.avgWaitTime && opts.medWaitTime === true) { |
| 59 | this.requiredStatistics.avgWaitTime = false |
| 60 | this.requiredStatistics.medWaitTime = opts.medWaitTime as boolean |
| 61 | } |
| 62 | if (this.requiredStatistics.medWaitTime && opts.medWaitTime === false) { |
| 63 | this.requiredStatistics.avgWaitTime = true |
| 64 | this.requiredStatistics.medWaitTime = opts.medWaitTime as boolean |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | /** @inheritDoc */ |
| 69 | public abstract reset (): boolean |
| 70 | |
| 71 | /** @inheritDoc */ |
| 72 | public abstract update (workerNodeKey: number): boolean |
| 73 | |
| 74 | /** @inheritDoc */ |
| 75 | public abstract choose (): number |
| 76 | |
| 77 | /** @inheritDoc */ |
| 78 | public abstract remove (workerNodeKey: number): boolean |
| 79 | |
| 80 | /** @inheritDoc */ |
| 81 | public setOptions (opts: WorkerChoiceStrategyOptions): void { |
| 82 | opts = opts ?? DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS |
| 83 | this.setRequiredStatistics(opts) |
| 84 | this.opts = opts |
| 85 | } |
| 86 | |
| 87 | /** |
| 88 | * Finds a free worker node key. |
| 89 | * |
| 90 | * @returns The free worker node key or `-1` if there is no free worker node. |
| 91 | */ |
| 92 | protected findFreeWorkerNodeKey (): number { |
| 93 | if (this.toggleFindLastFreeWorkerNodeKey) { |
| 94 | this.toggleFindLastFreeWorkerNodeKey = false |
| 95 | return this.findLastFreeWorkerNodeKey() |
| 96 | } |
| 97 | this.toggleFindLastFreeWorkerNodeKey = true |
| 98 | return this.findFirstFreeWorkerNodeKey() |
| 99 | } |
| 100 | |
| 101 | /** |
| 102 | * Gets the worker task runtime. |
| 103 | * If the required statistics are `avgRunTime`, the average runtime is returned. |
| 104 | * If the required statistics are `medRunTime`, the median runtime is returned. |
| 105 | * |
| 106 | * @param workerNodeKey - The worker node key. |
| 107 | * @returns The worker task runtime. |
| 108 | */ |
| 109 | protected getWorkerTaskRunTime (workerNodeKey: number): number { |
| 110 | return this.requiredStatistics.medRunTime |
| 111 | ? this.pool.workerNodes[workerNodeKey].tasksUsage.medRunTime |
| 112 | : this.pool.workerNodes[workerNodeKey].tasksUsage.avgRunTime |
| 113 | } |
| 114 | |
| 115 | /** |
| 116 | * Finds the first free worker node key based on the number of tasks the worker has applied. |
| 117 | * |
| 118 | * If a worker is found with `0` running tasks, it is detected as free and its worker node key is returned. |
| 119 | * |
| 120 | * If no free worker is found, `-1` is returned. |
| 121 | * |
| 122 | * @returns A worker node key if there is one, `-1` otherwise. |
| 123 | */ |
| 124 | private findFirstFreeWorkerNodeKey (): number { |
| 125 | return this.pool.workerNodes.findIndex(workerNode => { |
| 126 | return workerNode.tasksUsage.running === 0 |
| 127 | }) |
| 128 | } |
| 129 | |
| 130 | /** |
| 131 | * Finds the last free worker node key based on the number of tasks the worker has applied. |
| 132 | * |
| 133 | * If a worker is found with `0` running tasks, it is detected as free and its worker node key is returned. |
| 134 | * |
| 135 | * If no free worker is found, `-1` is returned. |
| 136 | * |
| 137 | * @returns A worker node key if there is one, `-1` otherwise. |
| 138 | */ |
| 139 | private findLastFreeWorkerNodeKey (): number { |
| 140 | // It requires node >= 18.0.0: |
| 141 | // return this.workerNodes.findLastIndex(workerNode => { |
| 142 | // return workerNode.tasksUsage.running === 0 |
| 143 | // }) |
| 144 | for ( |
| 145 | let workerNodeKey = this.pool.workerNodes.length - 1; |
| 146 | workerNodeKey >= 0; |
| 147 | workerNodeKey-- |
| 148 | ) { |
| 149 | if (this.pool.workerNodes[workerNodeKey].tasksUsage.running === 0) { |
| 150 | return workerNodeKey |
| 151 | } |
| 152 | } |
| 153 | return -1 |
| 154 | } |
| 155 | } |