-import crypto from 'node:crypto'
-import type { MessageValue, PromiseResponseWrapper } from '../utility-types'
+import { randomUUID } from 'node:crypto'
+import { performance } from 'node:perf_hooks'
+import type {
+ MessageValue,
+ PromiseResponseWrapper,
+ Task
+} from '../utility-types'
import {
+ DEFAULT_TASK_NAME,
DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS,
EMPTY_FUNCTION,
- median
+ isKillBehavior,
+ isPlainObject,
+ median,
+ round
} from '../utils'
-import { KillBehaviors, isKillBehavior } from '../worker/worker-options'
+import { KillBehaviors } from '../worker/worker-options'
import {
- PoolEvents,
type IPool,
+ PoolEmitter,
+ PoolEvents,
+ type PoolInfo,
type PoolOptions,
- type TasksQueueOptions,
- PoolType
+ type PoolType,
+ PoolTypes,
+ type TasksQueueOptions
} from './pool'
-import { PoolEmitter } from './pool'
-import type { IWorker, Task, TasksUsage, WorkerNode } from './worker'
+import type {
+ IWorker,
+ IWorkerNode,
+ MessageHandler,
+ WorkerInfo,
+ WorkerType,
+ WorkerUsage
+} from './worker'
import {
+ Measurements,
WorkerChoiceStrategies,
- type WorkerChoiceStrategy
+ type WorkerChoiceStrategy,
+ type WorkerChoiceStrategyOptions
} from './selection-strategies/selection-strategies-types'
import { WorkerChoiceStrategyContext } from './selection-strategies/worker-choice-strategy-context'
-import { CircularArray } from '../circular-array'
+import { version } from './version'
+import { WorkerNode } from './worker-node'
/**
* Base class that implements some shared logic for all poolifier pools.
*
* @typeParam Worker - Type of worker which manages this pool.
- * @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 abstract class AbstractPool<
Worker extends IWorker,
Response = unknown
> implements IPool<Worker, Data, Response> {
/** @inheritDoc */
- public readonly workerNodes: Array<WorkerNode<Worker, Data>> = []
+ public readonly workerNodes: Array<IWorkerNode<Worker, Data>> = []
/** @inheritDoc */
public readonly emitter?: PoolEmitter
/**
* Worker choice strategy context referencing a worker choice algorithm implementation.
- *
- * Default to a round robin algorithm.
*/
protected workerChoiceStrategyContext: WorkerChoiceStrategyContext<
Worker,
Response
>
+ /**
+ * The start timestamp of the pool.
+ */
+ private readonly startTimestamp
+
/**
* Constructs a new poolifier pool.
*
* @param numberOfWorkers - Number of workers that this pool should manage.
- * @param filePath - Path to the worker-file.
+ * @param filePath - Path to the worker file.
* @param opts - Options for the pool.
*/
public constructor (
- public readonly numberOfWorkers: number,
- public readonly filePath: string,
- public readonly opts: PoolOptions<Worker>
+ protected readonly numberOfWorkers: number,
+ protected readonly filePath: string,
+ protected readonly opts: PoolOptions<Worker>
) {
if (!this.isMain()) {
throw new Error('Cannot start a pool from a worker!')
this.checkFilePath(this.filePath)
this.checkPoolOptions(this.opts)
- this.chooseWorkerNode.bind(this)
- this.executeTask.bind(this)
- this.enqueueTask.bind(this)
- this.checkAndEmitEvents.bind(this)
-
- this.setupHook()
-
- for (let i = 1; i <= this.numberOfWorkers; i++) {
- this.createAndSetupWorker()
- }
+ this.chooseWorkerNode = this.chooseWorkerNode.bind(this)
+ this.executeTask = this.executeTask.bind(this)
+ this.enqueueTask = this.enqueueTask.bind(this)
+ this.checkAndEmitEvents = this.checkAndEmitEvents.bind(this)
if (this.opts.enableEvents === true) {
this.emitter = new PoolEmitter()
this.opts.workerChoiceStrategy,
this.opts.workerChoiceStrategyOptions
)
+
+ this.setupHook()
+
+ while (this.workerNodes.length < this.numberOfWorkers) {
+ this.createAndSetupWorker()
+ }
+
+ this.startTimestamp = performance.now()
}
private checkFilePath (filePath: string): void {
)
} else if (!Number.isSafeInteger(numberOfWorkers)) {
throw new TypeError(
- 'Cannot instantiate a pool with a non integer number of workers'
+ 'Cannot instantiate a pool with a non safe integer number of workers'
)
} else if (numberOfWorkers < 0) {
throw new RangeError(
'Cannot instantiate a pool with a negative number of workers'
)
- } else if (this.type === PoolType.FIXED && numberOfWorkers === 0) {
- throw new Error('Cannot instantiate a fixed pool with no worker')
+ } else if (this.type === PoolTypes.fixed && numberOfWorkers === 0) {
+ throw new RangeError('Cannot instantiate a fixed pool with zero worker')
}
}
- private checkPoolOptions (opts: PoolOptions<Worker>): void {
- this.opts.workerChoiceStrategy =
- opts.workerChoiceStrategy ?? WorkerChoiceStrategies.ROUND_ROBIN
- this.checkValidWorkerChoiceStrategy(this.opts.workerChoiceStrategy)
- this.opts.workerChoiceStrategyOptions =
- opts.workerChoiceStrategyOptions ?? DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
- this.opts.enableEvents = opts.enableEvents ?? true
- this.opts.enableTasksQueue = opts.enableTasksQueue ?? false
- if (this.opts.enableTasksQueue) {
- if ((opts.tasksQueueOptions?.concurrency as number) <= 0) {
- throw new Error(
- `Invalid worker tasks concurrency '${
- (opts.tasksQueueOptions as TasksQueueOptions).concurrency as number
- }'`
+ protected checkDynamicPoolSize (min: number, max: number): void {
+ if (this.type === PoolTypes.dynamic) {
+ if (min > max) {
+ throw new RangeError(
+ 'Cannot instantiate a dynamic pool with a maximum pool size inferior to the minimum pool size'
+ )
+ } else if (min === 0 && max === 0) {
+ throw new RangeError(
+ 'Cannot instantiate a dynamic pool with a minimum pool size and a maximum pool size equal to zero'
+ )
+ } else if (min === max) {
+ throw new RangeError(
+ 'Cannot instantiate a dynamic pool with a minimum pool size equal to the maximum pool size. Use a fixed pool instead'
)
}
- this.opts.tasksQueueOptions = {
- concurrency: opts.tasksQueueOptions?.concurrency ?? 1
+ }
+ }
+
+ private checkPoolOptions (opts: PoolOptions<Worker>): void {
+ if (isPlainObject(opts)) {
+ this.opts.workerChoiceStrategy =
+ opts.workerChoiceStrategy ?? WorkerChoiceStrategies.ROUND_ROBIN
+ this.checkValidWorkerChoiceStrategy(this.opts.workerChoiceStrategy)
+ this.opts.workerChoiceStrategyOptions =
+ opts.workerChoiceStrategyOptions ??
+ DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
+ this.checkValidWorkerChoiceStrategyOptions(
+ this.opts.workerChoiceStrategyOptions
+ )
+ this.opts.restartWorkerOnError = opts.restartWorkerOnError ?? true
+ this.opts.enableEvents = opts.enableEvents ?? true
+ this.opts.enableTasksQueue = opts.enableTasksQueue ?? false
+ if (this.opts.enableTasksQueue) {
+ this.checkValidTasksQueueOptions(
+ opts.tasksQueueOptions as TasksQueueOptions
+ )
+ this.opts.tasksQueueOptions = this.buildTasksQueueOptions(
+ opts.tasksQueueOptions as TasksQueueOptions
+ )
}
+ } else {
+ throw new TypeError('Invalid pool options: must be a plain object')
}
}
}
}
+ private checkValidWorkerChoiceStrategyOptions (
+ workerChoiceStrategyOptions: WorkerChoiceStrategyOptions
+ ): void {
+ if (!isPlainObject(workerChoiceStrategyOptions)) {
+ throw new TypeError(
+ 'Invalid worker choice strategy options: must be a plain object'
+ )
+ }
+ if (
+ workerChoiceStrategyOptions.weights != null &&
+ Object.keys(workerChoiceStrategyOptions.weights).length !== this.maxSize
+ ) {
+ throw new Error(
+ 'Invalid worker choice strategy options: must have a weight for each worker node'
+ )
+ }
+ if (
+ workerChoiceStrategyOptions.measurement != null &&
+ !Object.values(Measurements).includes(
+ workerChoiceStrategyOptions.measurement
+ )
+ ) {
+ throw new Error(
+ `Invalid worker choice strategy options: invalid measurement '${workerChoiceStrategyOptions.measurement}'`
+ )
+ }
+ }
+
+ private checkValidTasksQueueOptions (
+ tasksQueueOptions: TasksQueueOptions
+ ): void {
+ if (tasksQueueOptions != null && !isPlainObject(tasksQueueOptions)) {
+ throw new TypeError('Invalid tasks queue options: must be a plain object')
+ }
+ if (
+ tasksQueueOptions?.concurrency != null &&
+ !Number.isSafeInteger(tasksQueueOptions.concurrency)
+ ) {
+ throw new TypeError(
+ 'Invalid worker tasks concurrency: must be an integer'
+ )
+ }
+ if (
+ tasksQueueOptions?.concurrency != null &&
+ tasksQueueOptions.concurrency <= 0
+ ) {
+ throw new Error(
+ `Invalid worker tasks concurrency '${tasksQueueOptions.concurrency}'`
+ )
+ }
+ }
+
/** @inheritDoc */
- public abstract get type (): PoolType
+ public get info (): PoolInfo {
+ return {
+ version,
+ type: this.type,
+ worker: this.worker,
+ ready: this.ready,
+ strategy: this.opts.workerChoiceStrategy as WorkerChoiceStrategy,
+ minSize: this.minSize,
+ maxSize: this.maxSize,
+ ...(this.workerChoiceStrategyContext.getTaskStatisticsRequirements()
+ .runTime.aggregate &&
+ this.workerChoiceStrategyContext.getTaskStatisticsRequirements()
+ .waitTime.aggregate && { utilization: round(this.utilization) }),
+ workerNodes: this.workerNodes.length,
+ idleWorkerNodes: this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ workerNode.usage.tasks.executing === 0
+ ? accumulator + 1
+ : accumulator,
+ 0
+ ),
+ busyWorkerNodes: this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ workerNode.usage.tasks.executing > 0 ? accumulator + 1 : accumulator,
+ 0
+ ),
+ executedTasks: this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ accumulator + workerNode.usage.tasks.executed,
+ 0
+ ),
+ executingTasks: this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ accumulator + workerNode.usage.tasks.executing,
+ 0
+ ),
+ queuedTasks: this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ accumulator + workerNode.usage.tasks.queued,
+ 0
+ ),
+ maxQueuedTasks: this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ accumulator + (workerNode.usage.tasks?.maxQueued ?? 0),
+ 0
+ ),
+ failedTasks: this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ accumulator + workerNode.usage.tasks.failed,
+ 0
+ ),
+ ...(this.workerChoiceStrategyContext.getTaskStatisticsRequirements()
+ .runTime.aggregate && {
+ runTime: {
+ minimum: round(
+ Math.min(
+ ...this.workerNodes.map(
+ workerNode => workerNode.usage.runTime?.minimum ?? Infinity
+ )
+ )
+ ),
+ maximum: round(
+ Math.max(
+ ...this.workerNodes.map(
+ workerNode => workerNode.usage.runTime?.maximum ?? -Infinity
+ )
+ )
+ ),
+ average: round(
+ this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ accumulator + (workerNode.usage.runTime?.aggregate ?? 0),
+ 0
+ ) /
+ this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ accumulator + (workerNode.usage.tasks?.executed ?? 0),
+ 0
+ )
+ ),
+ ...(this.workerChoiceStrategyContext.getTaskStatisticsRequirements()
+ .runTime.median && {
+ median: round(
+ median(
+ this.workerNodes.map(
+ workerNode => workerNode.usage.runTime?.median ?? 0
+ )
+ )
+ )
+ })
+ }
+ }),
+ ...(this.workerChoiceStrategyContext.getTaskStatisticsRequirements()
+ .waitTime.aggregate && {
+ waitTime: {
+ minimum: round(
+ Math.min(
+ ...this.workerNodes.map(
+ workerNode => workerNode.usage.waitTime?.minimum ?? Infinity
+ )
+ )
+ ),
+ maximum: round(
+ Math.max(
+ ...this.workerNodes.map(
+ workerNode => workerNode.usage.waitTime?.maximum ?? -Infinity
+ )
+ )
+ ),
+ average: round(
+ this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ accumulator + (workerNode.usage.waitTime?.aggregate ?? 0),
+ 0
+ ) /
+ this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ accumulator + (workerNode.usage.tasks?.executed ?? 0),
+ 0
+ )
+ ),
+ ...(this.workerChoiceStrategyContext.getTaskStatisticsRequirements()
+ .waitTime.median && {
+ median: round(
+ median(
+ this.workerNodes.map(
+ workerNode => workerNode.usage.waitTime?.median ?? 0
+ )
+ )
+ )
+ })
+ }
+ })
+ }
+ }
+
+ private get starting (): boolean {
+ return (
+ this.workerNodes.length < this.minSize ||
+ (this.workerNodes.length >= this.minSize &&
+ this.workerNodes.some(workerNode => !workerNode.info.ready))
+ )
+ }
+
+ private get ready (): boolean {
+ return (
+ this.workerNodes.length >= this.minSize &&
+ this.workerNodes.every(workerNode => workerNode.info.ready)
+ )
+ }
/**
- * Number of tasks running in the pool.
+ * Gets the approximate pool utilization.
+ *
+ * @returns The pool utilization.
*/
- private get numberOfRunningTasks (): number {
- return this.workerNodes.reduce(
- (accumulator, workerNode) => accumulator + workerNode.tasksUsage.running,
+ private get utilization (): number {
+ const poolRunTimeCapacity =
+ (performance.now() - this.startTimestamp) * this.maxSize
+ const totalTasksRunTime = this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ accumulator + (workerNode.usage.runTime?.aggregate ?? 0),
+ 0
+ )
+ const totalTasksWaitTime = this.workerNodes.reduce(
+ (accumulator, workerNode) =>
+ accumulator + (workerNode.usage.waitTime?.aggregate ?? 0),
0
)
+ return (totalTasksRunTime + totalTasksWaitTime) / poolRunTimeCapacity
}
/**
- * Number of tasks queued in the pool.
+ * Pool type.
+ *
+ * If it is `'dynamic'`, it provides the `max` property.
+ */
+ protected abstract get type (): PoolType
+
+ /**
+ * Gets the worker type.
+ */
+ protected abstract get worker (): WorkerType
+
+ /**
+ * Pool minimum size.
+ */
+ protected abstract get minSize (): number
+
+ /**
+ * Pool maximum size.
*/
- private get numberOfQueuedTasks (): number {
- if (this.opts.enableTasksQueue === false) {
- return 0
+ protected abstract get maxSize (): number
+
+ /**
+ * Get the worker given its id.
+ *
+ * @param workerId - The worker id.
+ * @returns The worker if found in the pool worker nodes, `undefined` otherwise.
+ */
+ private getWorkerById (workerId: number): Worker | undefined {
+ return this.workerNodes.find(workerNode => workerNode.info.id === workerId)
+ ?.worker
+ }
+
+ private checkMessageWorkerId (message: MessageValue<Response>): void {
+ if (
+ message.workerId != null &&
+ this.getWorkerById(message.workerId) == null
+ ) {
+ throw new Error(
+ `Worker message received from unknown worker '${message.workerId}'`
+ )
}
- return this.workerNodes.reduce(
- (accumulator, workerNode) => accumulator + workerNode.tasksQueue.length,
- 0
- )
}
/**
* Gets the given worker its worker node key.
*
* @param worker - The worker.
- * @returns The worker node key if the worker is found in the pool worker nodes, `-1` otherwise.
+ * @returns The worker node key if found in the pool worker nodes, `-1` otherwise.
*/
private getWorkerNodeKey (worker: Worker): number {
return this.workerNodes.findIndex(
/** @inheritDoc */
public setWorkerChoiceStrategy (
- workerChoiceStrategy: WorkerChoiceStrategy
+ workerChoiceStrategy: WorkerChoiceStrategy,
+ workerChoiceStrategyOptions?: WorkerChoiceStrategyOptions
): void {
this.checkValidWorkerChoiceStrategy(workerChoiceStrategy)
this.opts.workerChoiceStrategy = workerChoiceStrategy
+ this.workerChoiceStrategyContext.setWorkerChoiceStrategy(
+ this.opts.workerChoiceStrategy
+ )
+ if (workerChoiceStrategyOptions != null) {
+ this.setWorkerChoiceStrategyOptions(workerChoiceStrategyOptions)
+ }
for (const workerNode of this.workerNodes) {
- this.setWorkerNodeTasksUsage(workerNode, {
- run: 0,
- running: 0,
- runTime: 0,
- runTimeHistory: new CircularArray(),
- avgRunTime: 0,
- medRunTime: 0,
- error: 0
- })
+ workerNode.resetUsage()
+ this.setWorkerStatistics(workerNode.worker)
}
- this.workerChoiceStrategyContext.setWorkerChoiceStrategy(
- workerChoiceStrategy
+ }
+
+ /** @inheritDoc */
+ public setWorkerChoiceStrategyOptions (
+ workerChoiceStrategyOptions: WorkerChoiceStrategyOptions
+ ): void {
+ this.checkValidWorkerChoiceStrategyOptions(workerChoiceStrategyOptions)
+ this.opts.workerChoiceStrategyOptions = workerChoiceStrategyOptions
+ this.workerChoiceStrategyContext.setOptions(
+ this.opts.workerChoiceStrategyOptions
)
}
/** @inheritDoc */
- public abstract get full (): boolean
+ public enableTasksQueue (
+ enable: boolean,
+ tasksQueueOptions?: TasksQueueOptions
+ ): void {
+ if (this.opts.enableTasksQueue === true && !enable) {
+ this.flushTasksQueues()
+ }
+ this.opts.enableTasksQueue = enable
+ this.setTasksQueueOptions(tasksQueueOptions as TasksQueueOptions)
+ }
/** @inheritDoc */
- public abstract get busy (): boolean
+ public setTasksQueueOptions (tasksQueueOptions: TasksQueueOptions): void {
+ if (this.opts.enableTasksQueue === true) {
+ this.checkValidTasksQueueOptions(tasksQueueOptions)
+ this.opts.tasksQueueOptions =
+ this.buildTasksQueueOptions(tasksQueueOptions)
+ } else if (this.opts.tasksQueueOptions != null) {
+ delete this.opts.tasksQueueOptions
+ }
+ }
- protected internalBusy (): boolean {
- return this.findFreeWorkerNodeKey() === -1
+ private buildTasksQueueOptions (
+ tasksQueueOptions: TasksQueueOptions
+ ): TasksQueueOptions {
+ return {
+ concurrency: tasksQueueOptions?.concurrency ?? 1
+ }
}
- /** @inheritDoc */
- public findFreeWorkerNodeKey (): number {
- return this.workerNodes.findIndex(workerNode => {
- return workerNode.tasksUsage?.running === 0
- })
+ /**
+ * Whether the pool is full or not.
+ *
+ * The pool filling boolean status.
+ */
+ protected get full (): boolean {
+ return this.workerNodes.length >= this.maxSize
+ }
+
+ /**
+ * Whether the pool is busy or not.
+ *
+ * The pool busyness boolean status.
+ */
+ protected abstract get busy (): boolean
+
+ /**
+ * Whether worker nodes are executing at least one task.
+ *
+ * @returns Worker nodes busyness boolean status.
+ */
+ protected internalBusy (): boolean {
+ return (
+ this.workerNodes.findIndex(workerNode => {
+ return workerNode.usage.tasks.executing === 0
+ }) === -1
+ )
}
/** @inheritDoc */
- public async execute (data: Data): Promise<Response> {
- const [workerNodeKey, workerNode] = this.chooseWorkerNode()
+ public async execute (data?: Data, name?: string): Promise<Response> {
+ const timestamp = performance.now()
+ const workerNodeKey = this.chooseWorkerNode()
const submittedTask: Task<Data> = {
+ name: name ?? DEFAULT_TASK_NAME,
// eslint-disable-next-line @typescript-eslint/consistent-type-assertions
data: data ?? ({} as Data),
- id: crypto.randomUUID()
+ timestamp,
+ workerId: this.getWorkerInfo(workerNodeKey).id as number,
+ id: randomUUID()
}
const res = new Promise<Response>((resolve, reject) => {
- this.promiseResponseMap.set(submittedTask.id, {
+ this.promiseResponseMap.set(submittedTask.id as string, {
resolve,
reject,
- worker: workerNode.worker
+ worker: this.workerNodes[workerNodeKey].worker
})
})
if (
this.opts.enableTasksQueue === true &&
(this.busy ||
- this.workerNodes[workerNodeKey].tasksUsage.running >=
+ this.workerNodes[workerNodeKey].usage.tasks.executing >=
((this.opts.tasksQueueOptions as TasksQueueOptions)
.concurrency as number))
) {
await Promise.all(
this.workerNodes.map(async (workerNode, workerNodeKey) => {
this.flushTasksQueue(workerNodeKey)
+ // FIXME: wait for tasks to be finished
+ const workerExitPromise = new Promise<void>(resolve => {
+ workerNode.worker.on('exit', () => {
+ resolve()
+ })
+ })
await this.destroyWorker(workerNode.worker)
+ await workerExitPromise
})
)
}
/**
- * Shutdowns the given worker.
+ * Terminates the given worker.
*
* @param worker - A worker within `workerNodes`.
*/
protected abstract destroyWorker (worker: Worker): void | Promise<void>
/**
- * Setup hook to execute code before worker node are created in the abstract constructor.
- * Can be overridden
+ * Setup hook to execute code before worker nodes are created in the abstract constructor.
+ * Can be overridden.
*
* @virtual
*/
* Can be overridden.
*
* @param workerNodeKey - The worker node key.
+ * @param task - The task to execute.
*/
- protected beforeTaskExecutionHook (workerNodeKey: number): void {
- ++this.workerNodes[workerNodeKey].tasksUsage.running
+ protected beforeTaskExecutionHook (
+ workerNodeKey: number,
+ task: Task<Data>
+ ): void {
+ const workerUsage = this.workerNodes[workerNodeKey].usage
+ ++workerUsage.tasks.executing
+ this.updateWaitTimeWorkerUsage(workerUsage, task)
+ const taskWorkerUsage = this.workerNodes[workerNodeKey].getTaskWorkerUsage(
+ task.name as string
+ ) as WorkerUsage
+ ++taskWorkerUsage.tasks.executing
+ this.updateWaitTimeWorkerUsage(taskWorkerUsage, task)
}
/**
worker: Worker,
message: MessageValue<Response>
): void {
- const workerTasksUsage = this.getWorkerTasksUsage(worker) as TasksUsage
- --workerTasksUsage.running
- ++workerTasksUsage.run
- if (message.error != null) {
- ++workerTasksUsage.error
- }
- if (this.workerChoiceStrategyContext.getRequiredStatistics().runTime) {
- workerTasksUsage.runTime += message.runTime ?? 0
+ const workerNodeKey = this.getWorkerNodeKey(worker)
+ const workerUsage = this.workerNodes[workerNodeKey].usage
+ this.updateTaskStatisticsWorkerUsage(workerUsage, message)
+ this.updateRunTimeWorkerUsage(workerUsage, message)
+ this.updateEluWorkerUsage(workerUsage, message)
+ const taskWorkerUsage = this.workerNodes[workerNodeKey].getTaskWorkerUsage(
+ message.name as string
+ ) as WorkerUsage
+ this.updateTaskStatisticsWorkerUsage(taskWorkerUsage, message)
+ this.updateRunTimeWorkerUsage(taskWorkerUsage, message)
+ this.updateEluWorkerUsage(taskWorkerUsage, message)
+ }
+
+ private updateTaskStatisticsWorkerUsage (
+ workerUsage: WorkerUsage,
+ message: MessageValue<Response>
+ ): void {
+ const workerTaskStatistics = workerUsage.tasks
+ --workerTaskStatistics.executing
+ if (message.taskError == null) {
+ ++workerTaskStatistics.executed
+ } else {
+ ++workerTaskStatistics.failed
+ }
+ }
+
+ private updateRunTimeWorkerUsage (
+ workerUsage: WorkerUsage,
+ message: MessageValue<Response>
+ ): void {
+ if (
+ this.workerChoiceStrategyContext.getTaskStatisticsRequirements().runTime
+ .aggregate
+ ) {
+ const taskRunTime = message.taskPerformance?.runTime ?? 0
+ workerUsage.runTime.aggregate =
+ (workerUsage.runTime.aggregate ?? 0) + taskRunTime
+ workerUsage.runTime.minimum = Math.min(
+ taskRunTime,
+ workerUsage.runTime?.minimum ?? Infinity
+ )
+ workerUsage.runTime.maximum = Math.max(
+ taskRunTime,
+ workerUsage.runTime?.maximum ?? -Infinity
+ )
+ if (
+ this.workerChoiceStrategyContext.getTaskStatisticsRequirements().runTime
+ .average &&
+ workerUsage.tasks.executed !== 0
+ ) {
+ workerUsage.runTime.average =
+ workerUsage.runTime.aggregate / workerUsage.tasks.executed
+ }
+ if (
+ this.workerChoiceStrategyContext.getTaskStatisticsRequirements().runTime
+ .median &&
+ message.taskPerformance?.runTime != null
+ ) {
+ workerUsage.runTime.history.push(message.taskPerformance.runTime)
+ workerUsage.runTime.median = median(workerUsage.runTime.history)
+ }
+ }
+ }
+
+ private updateWaitTimeWorkerUsage (
+ workerUsage: WorkerUsage,
+ task: Task<Data>
+ ): void {
+ const timestamp = performance.now()
+ const taskWaitTime = timestamp - (task.timestamp ?? timestamp)
+ if (
+ this.workerChoiceStrategyContext.getTaskStatisticsRequirements().waitTime
+ .aggregate
+ ) {
+ workerUsage.waitTime.aggregate =
+ (workerUsage.waitTime?.aggregate ?? 0) + taskWaitTime
+ workerUsage.waitTime.minimum = Math.min(
+ taskWaitTime,
+ workerUsage.waitTime?.minimum ?? Infinity
+ )
+ workerUsage.waitTime.maximum = Math.max(
+ taskWaitTime,
+ workerUsage.waitTime?.maximum ?? -Infinity
+ )
if (
- this.workerChoiceStrategyContext.getRequiredStatistics().avgRunTime &&
- workerTasksUsage.run !== 0
+ this.workerChoiceStrategyContext.getTaskStatisticsRequirements()
+ .waitTime.average &&
+ workerUsage.tasks.executed !== 0
) {
- workerTasksUsage.avgRunTime =
- workerTasksUsage.runTime / workerTasksUsage.run
+ workerUsage.waitTime.average =
+ workerUsage.waitTime.aggregate / workerUsage.tasks.executed
}
- if (this.workerChoiceStrategyContext.getRequiredStatistics().medRunTime) {
- workerTasksUsage.runTimeHistory.push(message.runTime ?? 0)
- workerTasksUsage.medRunTime = median(workerTasksUsage.runTimeHistory)
+ if (
+ this.workerChoiceStrategyContext.getTaskStatisticsRequirements()
+ .waitTime.median
+ ) {
+ workerUsage.waitTime.history.push(taskWaitTime)
+ workerUsage.waitTime.median = median(workerUsage.waitTime.history)
+ }
+ }
+ }
+
+ private updateEluWorkerUsage (
+ workerUsage: WorkerUsage,
+ message: MessageValue<Response>
+ ): void {
+ if (
+ this.workerChoiceStrategyContext.getTaskStatisticsRequirements().elu
+ .aggregate
+ ) {
+ if (message.taskPerformance?.elu != null) {
+ workerUsage.elu.idle.aggregate =
+ (workerUsage.elu.idle?.aggregate ?? 0) +
+ message.taskPerformance.elu.idle
+ workerUsage.elu.active.aggregate =
+ (workerUsage.elu.active?.aggregate ?? 0) +
+ message.taskPerformance.elu.active
+ if (workerUsage.elu.utilization != null) {
+ workerUsage.elu.utilization =
+ (workerUsage.elu.utilization +
+ message.taskPerformance.elu.utilization) /
+ 2
+ } else {
+ workerUsage.elu.utilization = message.taskPerformance.elu.utilization
+ }
+ workerUsage.elu.idle.minimum = Math.min(
+ message.taskPerformance.elu.idle,
+ workerUsage.elu.idle?.minimum ?? Infinity
+ )
+ workerUsage.elu.idle.maximum = Math.max(
+ message.taskPerformance.elu.idle,
+ workerUsage.elu.idle?.maximum ?? -Infinity
+ )
+ workerUsage.elu.active.minimum = Math.min(
+ message.taskPerformance.elu.active,
+ workerUsage.elu.active?.minimum ?? Infinity
+ )
+ workerUsage.elu.active.maximum = Math.max(
+ message.taskPerformance.elu.active,
+ workerUsage.elu.active?.maximum ?? -Infinity
+ )
+ if (
+ this.workerChoiceStrategyContext.getTaskStatisticsRequirements().elu
+ .average &&
+ workerUsage.tasks.executed !== 0
+ ) {
+ workerUsage.elu.idle.average =
+ workerUsage.elu.idle.aggregate / workerUsage.tasks.executed
+ workerUsage.elu.active.average =
+ workerUsage.elu.active.aggregate / workerUsage.tasks.executed
+ }
+ if (
+ this.workerChoiceStrategyContext.getTaskStatisticsRequirements().elu
+ .median
+ ) {
+ workerUsage.elu.idle.history.push(message.taskPerformance.elu.idle)
+ workerUsage.elu.active.history.push(
+ message.taskPerformance.elu.active
+ )
+ workerUsage.elu.idle.median = median(workerUsage.elu.idle.history)
+ workerUsage.elu.active.median = median(workerUsage.elu.active.history)
+ }
}
}
}
/**
* Chooses a worker node for the next task.
*
- * The default uses a round robin algorithm to distribute the load.
+ * The default worker choice strategy uses a round robin algorithm to distribute the tasks.
*
- * @returns [worker node key, worker node].
+ * @returns The worker node key
*/
- protected chooseWorkerNode (): [number, WorkerNode<Worker, Data>] {
- let workerNodeKey: number
- if (this.type === PoolType.DYNAMIC && !this.full && this.internalBusy()) {
- const workerCreated = this.createAndSetupWorker()
- this.registerWorkerMessageListener(workerCreated, message => {
- if (
- isKillBehavior(KillBehaviors.HARD, message.kill) ||
- (message.kill != null &&
- this.getWorkerTasksUsage(workerCreated)?.running === 0)
- ) {
- // Kill message received from the worker: no new tasks are submitted to that worker for a while ( > maxInactiveTime)
- this.flushTasksQueueByWorker(workerCreated)
- void this.destroyWorker(workerCreated)
- }
- })
- workerNodeKey = this.getWorkerNodeKey(workerCreated)
- } else {
- workerNodeKey = this.workerChoiceStrategyContext.execute()
+ private chooseWorkerNode (): number {
+ if (this.shallCreateDynamicWorker()) {
+ const worker = this.createAndSetupDynamicWorker()
+ if (
+ this.workerChoiceStrategyContext.getStrategyPolicy().useDynamicWorker
+ ) {
+ return this.getWorkerNodeKey(worker)
+ }
}
- return [workerNodeKey, this.workerNodes[workerNodeKey]]
+ return this.workerChoiceStrategyContext.execute()
+ }
+
+ /**
+ * Conditions for dynamic worker creation.
+ *
+ * @returns Whether to create a dynamic worker or not.
+ */
+ private shallCreateDynamicWorker (): boolean {
+ return this.type === PoolTypes.dynamic && !this.full && this.internalBusy()
}
/**
* @param worker - The worker which should register a listener.
* @param listener - The message listener callback.
*/
- protected abstract registerWorkerMessageListener<
- Message extends Data | Response
- >(worker: Worker, listener: (message: MessageValue<Message>) => void): void
+ private registerWorkerMessageListener<Message extends Data | Response>(
+ worker: Worker,
+ listener: (message: MessageValue<Message>) => void
+ ): void {
+ worker.on('message', listener as MessageHandler<Worker>)
+ }
/**
- * Returns a newly created worker.
+ * Creates a new worker.
+ *
+ * @returns Newly created worker.
*/
protected abstract createWorker (): Worker
/**
* Function that can be hooked up when a worker has been newly created and moved to the pool worker nodes.
- *
- * Can be used to update the `maxListeners` or binding the `main-worker`\<-\>`worker` connection if not bind by default.
+ * Can be overridden.
*
* @param worker - The newly created worker.
*/
- protected abstract afterWorkerSetup (worker: Worker): void
+ protected afterWorkerSetup (worker: Worker): void {
+ // Listen to worker messages.
+ this.registerWorkerMessageListener(worker, this.workerListener())
+ // Send startup message to worker.
+ this.sendToWorker(worker, {
+ ready: false,
+ workerId: this.getWorkerInfo(this.getWorkerNodeKey(worker)).id as number
+ })
+ // Setup worker task statistics computation.
+ this.setWorkerStatistics(worker)
+ }
/**
* Creates a new worker and sets it up completely in the pool worker nodes.
worker.on('message', this.opts.messageHandler ?? EMPTY_FUNCTION)
worker.on('error', this.opts.errorHandler ?? EMPTY_FUNCTION)
+ worker.on('error', error => {
+ if (this.emitter != null) {
+ this.emitter.emit(PoolEvents.error, error)
+ }
+ if (this.opts.enableTasksQueue === true) {
+ this.redistributeQueuedTasks(worker)
+ }
+ if (this.opts.restartWorkerOnError === true && !this.starting) {
+ if (this.getWorkerInfo(this.getWorkerNodeKey(worker)).dynamic) {
+ this.createAndSetupDynamicWorker()
+ } else {
+ this.createAndSetupWorker()
+ }
+ }
+ })
worker.on('online', this.opts.onlineHandler ?? EMPTY_FUNCTION)
worker.on('exit', this.opts.exitHandler ?? EMPTY_FUNCTION)
worker.once('exit', () => {
return worker
}
+ private redistributeQueuedTasks (worker: Worker): void {
+ const workerNodeKey = this.getWorkerNodeKey(worker)
+ while (this.tasksQueueSize(workerNodeKey) > 0) {
+ let targetWorkerNodeKey: number = workerNodeKey
+ let minQueuedTasks = Infinity
+ for (const [workerNodeId, workerNode] of this.workerNodes.entries()) {
+ if (
+ workerNodeId !== workerNodeKey &&
+ workerNode.usage.tasks.queued === 0
+ ) {
+ targetWorkerNodeKey = workerNodeId
+ break
+ }
+ if (
+ workerNodeId !== workerNodeKey &&
+ workerNode.usage.tasks.queued < minQueuedTasks
+ ) {
+ minQueuedTasks = workerNode.usage.tasks.queued
+ targetWorkerNodeKey = workerNodeId
+ }
+ }
+ this.enqueueTask(
+ targetWorkerNodeKey,
+ this.dequeueTask(workerNodeKey) as Task<Data>
+ )
+ }
+ }
+
+ /**
+ * Creates a new dynamic worker and sets it up completely in the pool worker nodes.
+ *
+ * @returns New, completely set up dynamic worker.
+ */
+ protected createAndSetupDynamicWorker (): Worker {
+ const worker = this.createAndSetupWorker()
+ this.registerWorkerMessageListener(worker, message => {
+ const workerNodeKey = this.getWorkerNodeKey(worker)
+ if (
+ isKillBehavior(KillBehaviors.HARD, message.kill) ||
+ (message.kill != null &&
+ ((this.opts.enableTasksQueue === false &&
+ this.workerNodes[workerNodeKey].usage.tasks.executing === 0) ||
+ (this.opts.enableTasksQueue === true &&
+ this.workerNodes[workerNodeKey].usage.tasks.executing === 0 &&
+ this.tasksQueueSize(workerNodeKey) === 0)))
+ ) {
+ // Kill message received from the worker: no new tasks are submitted to that worker for a while ( > maxInactiveTime)
+ void (this.destroyWorker(worker) as Promise<void>)
+ }
+ })
+ const workerInfo = this.getWorkerInfo(this.getWorkerNodeKey(worker))
+ workerInfo.dynamic = true
+ this.sendToWorker(worker, {
+ checkAlive: true,
+ workerId: workerInfo.id as number
+ })
+ return worker
+ }
+
/**
* This function is the listener registered for each worker message.
*
*/
protected workerListener (): (message: MessageValue<Response>) => void {
return message => {
- if (message.id != null) {
+ this.checkMessageWorkerId(message)
+ if (message.ready != null && message.workerId != null) {
+ // Worker ready message received
+ this.handleWorkerReadyMessage(message)
+ } else if (message.id != null) {
// Task execution response received
- const promiseResponse = this.promiseResponseMap.get(message.id)
- if (promiseResponse != null) {
- if (message.error != null) {
- promiseResponse.reject(message.error)
- } else {
- promiseResponse.resolve(message.data as Response)
- }
- this.afterTaskExecutionHook(promiseResponse.worker, message)
- this.promiseResponseMap.delete(message.id)
- const workerNodeKey = this.getWorkerNodeKey(promiseResponse.worker)
- if (
- this.opts.enableTasksQueue === true &&
- this.tasksQueueSize(workerNodeKey) > 0
- ) {
- this.executeTask(
- workerNodeKey,
- this.dequeueTask(workerNodeKey) as Task<Data>
- )
- }
+ this.handleTaskExecutionResponse(message)
+ }
+ }
+ }
+
+ private handleWorkerReadyMessage (message: MessageValue<Response>): void {
+ const worker = this.getWorkerById(message.workerId)
+ this.getWorkerInfo(this.getWorkerNodeKey(worker as Worker)).ready =
+ message.ready as boolean
+ if (this.emitter != null && this.ready) {
+ this.emitter.emit(PoolEvents.ready, this.info)
+ }
+ }
+
+ private handleTaskExecutionResponse (message: MessageValue<Response>): void {
+ const promiseResponse = this.promiseResponseMap.get(message.id as string)
+ if (promiseResponse != null) {
+ if (message.taskError != null) {
+ if (this.emitter != null) {
+ this.emitter.emit(PoolEvents.taskError, message.taskError)
}
+ promiseResponse.reject(message.taskError.message)
+ } else {
+ promiseResponse.resolve(message.data as Response)
+ }
+ this.afterTaskExecutionHook(promiseResponse.worker, message)
+ this.promiseResponseMap.delete(message.id as string)
+ const workerNodeKey = this.getWorkerNodeKey(promiseResponse.worker)
+ if (
+ this.opts.enableTasksQueue === true &&
+ this.tasksQueueSize(workerNodeKey) > 0
+ ) {
+ this.executeTask(
+ workerNodeKey,
+ this.dequeueTask(workerNodeKey) as Task<Data>
+ )
}
+ this.workerChoiceStrategyContext.update(workerNodeKey)
}
}
private checkAndEmitEvents (): void {
- if (this.opts.enableEvents === true) {
+ if (this.emitter != null) {
if (this.busy) {
- this.emitter?.emit(PoolEvents.busy)
+ this.emitter.emit(PoolEvents.busy, this.info)
}
- if (this.type === PoolType.DYNAMIC && this.full) {
- this.emitter?.emit(PoolEvents.full)
+ if (this.type === PoolTypes.dynamic && this.full) {
+ this.emitter.emit(PoolEvents.full, this.info)
}
}
}
/**
- * Sets the given worker node its tasks usage in the pool.
+ * Gets the worker information.
*
- * @param workerNode - The worker node.
- * @param tasksUsage - The worker node tasks usage.
- */
- private setWorkerNodeTasksUsage (
- workerNode: WorkerNode<Worker, Data>,
- tasksUsage: TasksUsage
- ): void {
- workerNode.tasksUsage = tasksUsage
- }
-
- /**
- * Gets the given worker its tasks usage in the pool.
- *
- * @param worker - The worker.
- * @returns The worker tasks usage.
+ * @param workerNodeKey - The worker node key.
*/
- private getWorkerTasksUsage (worker: Worker): TasksUsage | undefined {
- const workerNodeKey = this.getWorkerNodeKey(worker)
- if (workerNodeKey !== -1) {
- return this.workerNodes[workerNodeKey].tasksUsage
- }
- throw new Error('Worker could not be found in the pool worker nodes')
+ private getWorkerInfo (workerNodeKey: number): WorkerInfo {
+ return this.workerNodes[workerNodeKey].info
}
/**
* @returns The worker nodes length.
*/
private pushWorkerNode (worker: Worker): number {
- return this.workerNodes.push({
- worker,
- tasksUsage: {
- run: 0,
- running: 0,
- runTime: 0,
- runTimeHistory: new CircularArray(),
- avgRunTime: 0,
- medRunTime: 0,
- error: 0
- },
- tasksQueue: []
- })
- }
-
- /**
- * Sets the given worker in the pool worker nodes.
- *
- * @param workerNodeKey - The worker node key.
- * @param worker - The worker.
- * @param tasksUsage - The worker tasks usage.
- * @param tasksQueue - The worker task queue.
- */
- private setWorkerNode (
- workerNodeKey: number,
- worker: Worker,
- tasksUsage: TasksUsage,
- tasksQueue: Array<Task<Data>>
- ): void {
- this.workerNodes[workerNodeKey] = {
- worker,
- tasksUsage,
- tasksQueue
- }
+ return this.workerNodes.push(new WorkerNode(worker, this.worker))
}
/**
*/
private removeWorkerNode (worker: Worker): void {
const workerNodeKey = this.getWorkerNodeKey(worker)
- this.workerNodes.splice(workerNodeKey, 1)
- this.workerChoiceStrategyContext.remove(workerNodeKey)
+ if (workerNodeKey !== -1) {
+ this.workerNodes.splice(workerNodeKey, 1)
+ this.workerChoiceStrategyContext.remove(workerNodeKey)
+ }
}
private executeTask (workerNodeKey: number, task: Task<Data>): void {
- this.beforeTaskExecutionHook(workerNodeKey)
+ this.beforeTaskExecutionHook(workerNodeKey, task)
this.sendToWorker(this.workerNodes[workerNodeKey].worker, task)
}
private enqueueTask (workerNodeKey: number, task: Task<Data>): number {
- return this.workerNodes[workerNodeKey].tasksQueue.push(task)
+ return this.workerNodes[workerNodeKey].enqueueTask(task)
}
private dequeueTask (workerNodeKey: number): Task<Data> | undefined {
- return this.workerNodes[workerNodeKey].tasksQueue.shift()
+ return this.workerNodes[workerNodeKey].dequeueTask()
}
private tasksQueueSize (workerNodeKey: number): number {
- return this.workerNodes[workerNodeKey].tasksQueue.length
+ return this.workerNodes[workerNodeKey].tasksQueueSize()
}
private flushTasksQueue (workerNodeKey: number): void {
- if (this.tasksQueueSize(workerNodeKey) > 0) {
- for (const task of this.workerNodes[workerNodeKey].tasksQueue) {
- this.executeTask(workerNodeKey, task)
- }
+ while (this.tasksQueueSize(workerNodeKey) > 0) {
+ this.executeTask(
+ workerNodeKey,
+ this.dequeueTask(workerNodeKey) as Task<Data>
+ )
}
+ this.workerNodes[workerNodeKey].clearTasksQueue()
}
- private flushTasksQueueByWorker (worker: Worker): void {
- const workerNodeKey = this.getWorkerNodeKey(worker)
- this.flushTasksQueue(workerNodeKey)
+ private flushTasksQueues (): void {
+ for (const [workerNodeKey] of this.workerNodes.entries()) {
+ this.flushTasksQueue(workerNodeKey)
+ }
+ }
+
+ private setWorkerStatistics (worker: Worker): void {
+ this.sendToWorker(worker, {
+ statistics: {
+ runTime:
+ this.workerChoiceStrategyContext.getTaskStatisticsRequirements()
+ .runTime.aggregate,
+ elu: this.workerChoiceStrategyContext.getTaskStatisticsRequirements()
+ .elu.aggregate
+ },
+ workerId: this.getWorkerInfo(this.getWorkerNodeKey(worker)).id as number
+ })
}
}