-import { cpus } from 'node:os'
-import type { IPoolInternal } from '../pool-internal'
-import type { IPoolWorker } from '../pool-worker'
+import type { IWorker } from '../worker'
+import type { IPool } from '../pool'
+import { DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS } from '../../utils'
import { AbstractWorkerChoiceStrategy } from './abstract-worker-choice-strategy'
import type {
IWorkerChoiceStrategy,
- RequiredStatistics
+ InternalWorkerChoiceStrategyOptions,
+ TaskStatisticsRequirements
} from './selection-strategies-types'
-/**
- * Virtual task runtime.
- */
-interface TaskRunTime {
- weight: number
- runTime: number
-}
-
/**
* Selects the next worker with a weighted round robin scheduling algorithm.
* Loosely modeled after the weighted round robin queueing algorithm: https://en.wikipedia.org/wiki/Weighted_round_robin.
*
* @typeParam Worker - Type of worker which manages the strategy.
- * @typeParam Data - Type of data sent to the worker. This can only be serializable data.
- * @typeParam Response - Type of response of execution. This can only be serializable data.
+ * @typeParam Data - Type of data sent to the worker. This can only be structured-cloneable data.
+ * @typeParam Response - Type of execution response. This can only be structured-cloneable data.
*/
export class WeightedRoundRobinWorkerChoiceStrategy<
- Worker extends IPoolWorker,
- Data,
- Response
+ Worker extends IWorker,
+ Data = unknown,
+ Response = unknown
>
extends AbstractWorkerChoiceStrategy<Worker, Data, Response>
implements IWorkerChoiceStrategy {
- /** {@inheritDoc} */
- public readonly requiredStatistics: RequiredStatistics = {
- runTime: true
+ /** @inheritDoc */
+ public readonly taskStatisticsRequirements: TaskStatisticsRequirements = {
+ runTime: {
+ aggregate: true,
+ average: true,
+ median: false
+ },
+ waitTime: DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS,
+ elu: DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS
}
/**
- * Worker id where the current task will be submitted.
- */
- private currentWorkerId: number = 0
- /**
- * Default worker weight.
- */
- private readonly defaultWorkerWeight: number
- /**
- * Per worker virtual task runtime map.
+ * Worker node virtual task runtime.
*/
- private readonly workersTaskRunTime: Map<number, TaskRunTime> = new Map<
- number,
- TaskRunTime
- >()
+ private workerNodeVirtualTaskRunTime: number = 0
- /**
- * Constructs a worker choice strategy that selects with a weighted round robin scheduling algorithm.
- *
- * @param pool - The pool instance.
- */
- public constructor (pool: IPoolInternal<Worker, Data, Response>) {
- super(pool)
- this.defaultWorkerWeight = this.computeWorkerWeight()
- this.initWorkersTaskRunTime()
+ /** @inheritDoc */
+ public constructor (
+ pool: IPool<Worker, Data, Response>,
+ opts: InternalWorkerChoiceStrategyOptions
+ ) {
+ super(pool, opts)
+ this.setTaskStatisticsRequirements(this.opts)
}
- /** {@inheritDoc} */
+ /** @inheritDoc */
public reset (): boolean {
- this.currentWorkerId = 0
- this.workersTaskRunTime.clear()
- this.initWorkersTaskRunTime()
+ this.resetWorkerNodeKeyProperties()
+ this.workerNodeVirtualTaskRunTime = 0
return true
}
- /** {@inheritDoc} */
- public choose (): number {
- const chosenWorkerKey = this.currentWorkerId
- if (this.isDynamicPool && !this.workersTaskRunTime.has(chosenWorkerKey)) {
- this.initWorkerTaskRunTime(chosenWorkerKey)
- }
- const workerTaskRunTime =
- this.workersTaskRunTime.get(chosenWorkerKey)?.runTime ?? 0
- const workerTaskWeight =
- this.workersTaskRunTime.get(chosenWorkerKey)?.weight ??
- this.defaultWorkerWeight
- if (workerTaskRunTime < workerTaskWeight) {
- this.setWorkerTaskRunTime(
- chosenWorkerKey,
- workerTaskWeight,
- workerTaskRunTime +
- (this.getWorkerVirtualTaskRunTime(chosenWorkerKey) ?? 0)
- )
- } else {
- this.currentWorkerId =
- this.currentWorkerId === this.pool.workers.length - 1
- ? 0
- : this.currentWorkerId + 1
- this.setWorkerTaskRunTime(this.currentWorkerId, workerTaskWeight, 0)
- }
- return chosenWorkerKey
+ /** @inheritDoc */
+ public update (): boolean {
+ return true
+ }
+
+ /** @inheritDoc */
+ public choose (): number | undefined {
+ this.setPreviousWorkerNodeKey(this.nextWorkerNodeKey)
+ this.weightedRoundRobinNextWorkerNodeKey()
+ this.checkNextWorkerNodeReadiness()
+ return this.nextWorkerNodeKey
}
- /** {@inheritDoc} */
- public remove (workerKey: number): boolean {
- if (this.currentWorkerId === workerKey) {
- this.currentWorkerId =
- this.currentWorkerId > this.pool.workers.length - 1
- ? this.pool.workers.length - 1
- : this.currentWorkerId
+ /** @inheritDoc */
+ public remove (workerNodeKey: number): boolean {
+ if (this.pool.workerNodes.length === 0) {
+ this.reset()
}
- const workerDeleted = this.workersTaskRunTime.delete(workerKey)
- for (const [key, value] of this.workersTaskRunTime) {
- if (key > workerKey) {
- this.workersTaskRunTime.set(key - 1, value)
+ if (this.nextWorkerNodeKey === workerNodeKey) {
+ this.workerNodeVirtualTaskRunTime = 0
+ if (this.nextWorkerNodeKey > this.pool.workerNodes.length - 1) {
+ this.nextWorkerNodeKey = this.pool.workerNodes.length - 1
}
}
- return workerDeleted
- }
-
- private initWorkersTaskRunTime (): void {
- for (const [index] of this.pool.workers.entries()) {
- this.initWorkerTaskRunTime(index)
+ if (
+ this.previousWorkerNodeKey === workerNodeKey &&
+ this.previousWorkerNodeKey > this.pool.workerNodes.length - 1
+ ) {
+ this.previousWorkerNodeKey = this.pool.workerNodes.length - 1
}
+ return true
}
- private initWorkerTaskRunTime (workerKey: number): void {
- this.setWorkerTaskRunTime(workerKey, this.defaultWorkerWeight, 0)
- }
-
- private setWorkerTaskRunTime (
- workerKey: number,
- weight: number,
- runTime: number
- ): void {
- this.workersTaskRunTime.set(workerKey, {
- weight,
- runTime
- })
- }
-
- private getWorkerVirtualTaskRunTime (workerKey: number): number {
- return this.pool.workers[workerKey].tasksUsage.avgRunTime
- }
-
- private computeWorkerWeight (): number {
- let cpusCycleTimeWeight = 0
- for (const cpu of cpus()) {
- // CPU estimated cycle time
- const numberOfDigits = cpu.speed.toString().length - 1
- const cpuCycleTime = 1 / (cpu.speed / Math.pow(10, numberOfDigits))
- cpusCycleTimeWeight += cpuCycleTime * Math.pow(10, numberOfDigits)
+ private weightedRoundRobinNextWorkerNodeKey (): number | undefined {
+ const workerWeight = this.opts.weights?.[
+ this.nextWorkerNodeKey ?? this.previousWorkerNodeKey
+ ] as number
+ if (this.workerNodeVirtualTaskRunTime < workerWeight) {
+ this.workerNodeVirtualTaskRunTime =
+ this.workerNodeVirtualTaskRunTime +
+ this.getWorkerNodeTaskRunTime(
+ this.nextWorkerNodeKey ?? this.previousWorkerNodeKey
+ )
+ } else {
+ this.nextWorkerNodeKey =
+ this.nextWorkerNodeKey === this.pool.workerNodes.length - 1
+ ? 0
+ : (this.nextWorkerNodeKey ?? this.previousWorkerNodeKey) + 1
+ this.workerNodeVirtualTaskRunTime = 0
}
- return Math.round(cpusCycleTimeWeight / cpus().length)
+ return this.nextWorkerNodeKey
}
}