MessageValue,
PromiseWorkerResponseWrapper
} from '../utility-types'
-import type { IPoolInternal } from './pool-internal'
-import { PoolEmitter } from './pool-internal'
-import type { WorkerChoiceStrategy } from './selection-strategies'
+import { EMPTY_FUNCTION } from '../utils'
+import { isKillBehavior, KillBehaviors } from '../worker/worker-options'
+import type { PoolOptions } from './pool'
+import { PoolEmitter } from './pool'
+import type { IPoolInternal, TasksUsage } from './pool-internal'
+import { PoolType } from './pool-internal'
+import type { IPoolWorker } from './pool-worker'
import {
WorkerChoiceStrategies,
- WorkerChoiceStrategyContext
-} from './selection-strategies'
+ WorkerChoiceStrategy
+} from './selection-strategies/selection-strategies-types'
+import { WorkerChoiceStrategyContext } from './selection-strategies/worker-choice-strategy-context'
/**
- * An intentional empty function.
- */
-const EMPTY_FUNCTION: () => void = () => {
- /* Intentionally empty */
-}
-
-/**
- * Callback invoked if the worker raised an error.
- */
-export type ErrorHandler<Worker> = (this: Worker, e: Error) => void
-
-/**
- * Callback invoked when the worker has started successfully.
- */
-export type OnlineHandler<Worker> = (this: Worker) => void
-
-/**
- * Callback invoked when the worker exits successfully.
- */
-export type ExitHandler<Worker> = (this: Worker, code: number) => void
-
-/**
- * Basic interface that describes the minimum required implementation of listener events for a pool-worker.
- */
-export interface IWorker {
- /**
- * Register a listener to the error event.
- *
- * @param event `'error'`.
- * @param handler The error handler.
- */
- on(event: 'error', handler: ErrorHandler<this>): void
- /**
- * Register a listener to the online event.
- *
- * @param event `'online'`.
- * @param handler The online handler.
- */
- on(event: 'online', handler: OnlineHandler<this>): void
- /**
- * Register a listener to the exit event.
- *
- * @param event `'exit'`.
- * @param handler The exit handler.
- */
- on(event: 'exit', handler: ExitHandler<this>): void
- /**
- * Register a listener to the exit event that will only performed once.
- *
- * @param event `'exit'`.
- * @param handler The exit handler.
- */
- once(event: 'exit', handler: ExitHandler<this>): void
-}
-
-/**
- * Options for a poolifier pool.
- */
-export interface PoolOptions<Worker> {
- /**
- * A function that will listen for error event on each worker.
- */
- errorHandler?: ErrorHandler<Worker>
- /**
- * A function that will listen for online event on each worker.
- */
- onlineHandler?: OnlineHandler<Worker>
- /**
- * A function that will listen for exit event on each worker.
- */
- exitHandler?: ExitHandler<Worker>
- /**
- * This is just to avoid non-useful warning messages.
- *
- * Will be used to set `maxListeners` on event emitters (workers are event emitters).
- *
- * @default 1000
- * @see [Node events emitter.setMaxListeners(n)](https://nodejs.org/api/events.html#events_emitter_setmaxlisteners_n)
- */
- maxTasks?: number
- /**
- * The work choice strategy to use in this pool.
- */
- workerChoiceStrategy?: WorkerChoiceStrategy
-}
-
-/**
- * Base class containing some shared logic for all poolifier pools.
+ * Base class that implements some shared logic for all poolifier pools.
*
* @template Worker Type of worker which manages this pool.
* @template Data Type of data sent to the worker. This can only be serializable data.
* @template Response Type of response of execution. This can only be serializable data.
*/
export abstract class AbstractPool<
- Worker extends IWorker,
+ Worker extends IPoolWorker,
Data = unknown,
Response = unknown
> implements IPoolInternal<Worker, Data, Response> {
+ /** @inheritDoc */
+ public readonly workers: Worker[] = []
+
+ /** @inheritDoc */
+ public readonly workersTasksUsage: Map<Worker, TasksUsage> = new Map<
+ Worker,
+ TasksUsage
+ >()
+
+ /** @inheritDoc */
+ public readonly emitter?: PoolEmitter
+
/**
* The promise map.
*
- * - `key`: This is the message ID of each submitted task.
+ * - `key`: This is the message Id of each submitted task.
* - `value`: An object that contains the worker, the resolve function and the reject function.
*
* When we receive a message from the worker we get a map entry and resolve/reject the promise based on the message.
PromiseWorkerResponseWrapper<Worker, Response>
> = new Map<number, PromiseWorkerResponseWrapper<Worker, Response>>()
- /** @inheritdoc */
- public readonly workers: Worker[] = []
-
- /** @inheritdoc */
- public readonly tasks: Map<Worker, number> = new Map<Worker, number>()
-
- /** @inheritdoc */
- public readonly emitter: PoolEmitter
-
/**
- * ID of the next message.
+ * Id of the next message.
*/
protected nextMessageId: number = 0
*
* @param numberOfWorkers Number of workers that this pool should manage.
* @param filePath Path to the worker-file.
- * @param opts Options for the pool. Default: `{ maxTasks: 1000 }`
+ * @param opts Options for the pool.
*/
public constructor (
public readonly numberOfWorkers: number,
public readonly filePath: string,
- public readonly opts: PoolOptions<Worker> = { maxTasks: 1000 }
+ public readonly opts: PoolOptions<Worker>
) {
- if (!this.isMain()) {
+ if (this.isMain() === false) {
throw new Error('Cannot start a pool from a worker!')
}
this.checkNumberOfWorkers(this.numberOfWorkers)
this.checkFilePath(this.filePath)
+ this.checkPoolOptions(this.opts)
this.setupHook()
for (let i = 1; i <= this.numberOfWorkers; i++) {
this.createAndSetupWorker()
}
- this.emitter = new PoolEmitter()
+ if (this.opts.enableEvents === true) {
+ this.emitter = new PoolEmitter()
+ }
this.workerChoiceStrategyContext = new WorkerChoiceStrategyContext(
this,
- opts.workerChoiceStrategy ?? WorkerChoiceStrategies.ROUND_ROBIN
+ () => {
+ const workerCreated = this.createAndSetupWorker()
+ this.registerWorkerMessageListener(workerCreated, message => {
+ if (
+ isKillBehavior(KillBehaviors.HARD, message.kill) ||
+ this.getWorkerRunningTasks(workerCreated) === 0
+ ) {
+ // Kill received from the worker, means that no new tasks are submitted to that worker for a while ( > maxInactiveTime)
+ this.destroyWorker(workerCreated) as void
+ }
+ })
+ return workerCreated
+ },
+ this.opts.workerChoiceStrategy
)
}
throw new Error(
'Cannot instantiate a pool without specifying the number of workers'
)
- } else if (!Number.isSafeInteger(numberOfWorkers)) {
- throw new Error(
+ } else if (Number.isSafeInteger(numberOfWorkers) === false) {
+ throw new TypeError(
'Cannot instantiate a pool with a non integer number of workers'
)
} else if (numberOfWorkers < 0) {
- throw new Error(
+ throw new RangeError(
'Cannot instantiate a pool with a negative number of workers'
)
- } else if (!this.isDynamic() && numberOfWorkers === 0) {
+ } else if (this.type === PoolType.FIXED && numberOfWorkers === 0) {
throw new Error('Cannot instantiate a fixed pool with no worker')
}
}
- /** @inheritdoc */
- public isDynamic (): boolean {
- return false
+ private checkPoolOptions (opts: PoolOptions<Worker>): void {
+ this.opts.workerChoiceStrategy =
+ opts.workerChoiceStrategy ?? WorkerChoiceStrategies.ROUND_ROBIN
+ this.opts.enableEvents = opts.enableEvents ?? true
+ }
+
+ /** @inheritDoc */
+ public abstract get type (): PoolType
+
+ /** @inheritDoc */
+ public get numberOfRunningTasks (): number {
+ return this.promiseMap.size
+ }
+
+ /** @inheritDoc */
+ public getWorkerIndex (worker: Worker): number {
+ return this.workers.indexOf(worker)
+ }
+
+ /** @inheritDoc */
+ public getWorkerRunningTasks (worker: Worker): number | undefined {
+ return this.workersTasksUsage.get(worker)?.running
}
- /** @inheritdoc */
+ /** @inheritDoc */
+ public getWorkerAverageTasksRunTime (worker: Worker): number | undefined {
+ return this.workersTasksUsage.get(worker)?.avgRunTime
+ }
+
+ /** @inheritDoc */
public setWorkerChoiceStrategy (
workerChoiceStrategy: WorkerChoiceStrategy
): void {
+ this.opts.workerChoiceStrategy = workerChoiceStrategy
+ for (const worker of this.workers) {
+ this.resetWorkerTasksUsage(worker)
+ }
this.workerChoiceStrategyContext.setWorkerChoiceStrategy(
workerChoiceStrategy
)
}
- /** @inheritdoc */
+ /** @inheritDoc */
+ public abstract get busy (): boolean
+
+ protected internalGetBusyStatus (): boolean {
+ return (
+ this.numberOfRunningTasks >= this.numberOfWorkers &&
+ this.findFreeWorker() === false
+ )
+ }
+
+ /** @inheritDoc */
+ public findFreeWorker (): Worker | false {
+ for (const worker of this.workers) {
+ if (this.getWorkerRunningTasks(worker) === 0) {
+ // A worker is free, return the matching worker
+ return worker
+ }
+ }
+ return false
+ }
+
+ /** @inheritDoc */
public execute (data: Data): Promise<Response> {
// Configure worker to handle message with the specified task
const worker = this.chooseWorker()
- this.increaseWorkersTask(worker)
- const messageId = ++this.nextMessageId
- const res = this.internalExecute(worker, messageId)
- this.sendToWorker(worker, { data: data || ({} as Data), id: messageId })
+ const res = this.internalExecute(worker, this.nextMessageId)
+ this.checkAndEmitBusy()
+ this.sendToWorker(worker, {
+ data: data ?? ({} as Data),
+ id: this.nextMessageId
+ })
+ ++this.nextMessageId
return res
}
- /** @inheritdoc */
+ /** @inheritDoc */
public async destroy (): Promise<void> {
await Promise.all(this.workers.map(worker => this.destroyWorker(worker)))
}
- /** @inheritdoc */
- public abstract destroyWorker (worker: Worker): void | Promise<void>
+ /**
+ * Shutdowns given worker.
+ *
+ * @param worker A worker within `workers`.
+ */
+ protected abstract destroyWorker (worker: Worker): void | Promise<void>
/**
* Setup hook that can be overridden by a Poolifier pool implementation
protected abstract isMain (): boolean
/**
- * Increase the number of tasks that the given workers has done.
+ * Hook executed before the worker task promise resolution.
+ * Can be overridden.
*
- * @param worker Worker whose tasks are increased.
+ * @param worker The worker.
*/
- protected increaseWorkersTask (worker: Worker): void {
- this.stepWorkerNumberOfTasks(worker, 1)
+ protected beforePromiseWorkerResponseHook (worker: Worker): void {
+ this.increaseWorkerRunningTasks(worker)
}
/**
- * Decrease the number of tasks that the given workers has done.
+ * Hook executed after the worker task promise resolution.
+ * Can be overridden.
*
- * @param worker Worker whose tasks are decreased.
+ * @param message The received message.
+ * @param promise The Promise response.
*/
- protected decreaseWorkersTasks (worker: Worker): void {
- this.stepWorkerNumberOfTasks(worker, -1)
- }
-
- /**
- * Step the number of tasks that the given workers has done.
- *
- * @param worker Worker whose tasks are set.
- * @param step Worker number of tasks step.
- */
- private stepWorkerNumberOfTasks (worker: Worker, step: number): void {
- const numberOfTasksInProgress = this.tasks.get(worker)
- if (numberOfTasksInProgress !== undefined) {
- this.tasks.set(worker, numberOfTasksInProgress + step)
- } else {
- throw Error('Worker could not be found in tasks map')
- }
+ protected afterPromiseWorkerResponseHook (
+ message: MessageValue<Response>,
+ promise: PromiseWorkerResponseWrapper<Worker, Response>
+ ): void {
+ this.decreaseWorkerRunningTasks(promise.worker)
+ this.stepWorkerRunTasks(promise.worker, 1)
+ this.updateWorkerTasksRunTime(promise.worker, message.taskRunTime)
}
/**
* Removes the given worker from the pool.
*
- * @param worker Worker that will be removed.
+ * @param worker The worker that will be removed.
*/
protected removeWorker (worker: Worker): void {
// Clean worker from data structure
- const workerIndex = this.workers.indexOf(worker)
- this.workers.splice(workerIndex, 1)
- this.tasks.delete(worker)
+ this.workers.splice(this.getWorkerIndex(worker), 1)
+ this.removeWorkerTasksUsage(worker)
}
/**
- * Choose a worker for the next task.
+ * Chooses a worker for the next task.
*
* The default implementation uses a round robin algorithm to distribute the load.
*
}
/**
- * Send a message to the given worker.
+ * Sends a message to the given worker.
*
* @param worker The worker which should receive the message.
* @param message The message.
message: MessageValue<Data>
): void
- /** @inheritdoc */
- public abstract registerWorkerMessageListener<
+ /**
+ * Registers a listener callback on a given worker.
+ *
+ * @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
worker: Worker,
messageId: number
): Promise<Response> {
+ this.beforePromiseWorkerResponseHook(worker)
return new Promise<Response>((resolve, reject) => {
this.promiseMap.set(messageId, { resolve, reject, worker })
})
*/
protected abstract afterWorkerSetup (worker: Worker): void
- /** @inheritdoc */
- public createAndSetupWorker (): Worker {
- const worker: Worker = this.createWorker()
+ /**
+ * Creates a new worker for this pool and sets it up completely.
+ *
+ * @returns New, completely set up worker.
+ */
+ protected createAndSetupWorker (): Worker {
+ const worker = this.createWorker()
+ worker.on('message', this.opts.messageHandler ?? EMPTY_FUNCTION)
worker.on('error', this.opts.errorHandler ?? EMPTY_FUNCTION)
worker.on('online', this.opts.onlineHandler ?? EMPTY_FUNCTION)
worker.on('exit', this.opts.exitHandler ?? EMPTY_FUNCTION)
this.workers.push(worker)
- // Init tasks map
- this.tasks.set(worker, 0)
+ // Init worker tasks usage map
+ this.initWorkerTasksUsage(worker)
this.afterWorkerSetup(worker)
/**
* This function is the listener registered for each worker.
*
- * @returns The listener function to execute when a message is sent from a worker.
+ * @returns The listener function to execute when a message is received from a worker.
*/
protected workerListener (): (message: MessageValue<Response>) => void {
- const listener: (message: MessageValue<Response>) => void = message => {
- if (message.id) {
- const value = this.promiseMap.get(message.id)
- if (value) {
- this.decreaseWorkersTasks(value.worker)
- if (message.error) value.reject(message.error)
- else value.resolve(message.data as Response)
+ return message => {
+ if (message.id !== undefined) {
+ const promise = this.promiseMap.get(message.id)
+ if (promise !== undefined) {
+ if (message.error) {
+ promise.reject(message.error)
+ } else {
+ promise.resolve(message.data as Response)
+ }
+ this.afterPromiseWorkerResponseHook(message, promise)
this.promiseMap.delete(message.id)
}
}
}
- return listener
+ }
+
+ private checkAndEmitBusy (): void {
+ if (this.opts.enableEvents === true && this.busy === true) {
+ this.emitter?.emit('busy')
+ }
+ }
+
+ /**
+ * Increases the number of tasks that the given worker has applied.
+ *
+ * @param worker Worker which running tasks is increased.
+ */
+ private increaseWorkerRunningTasks (worker: Worker): void {
+ this.stepWorkerRunningTasks(worker, 1)
+ }
+
+ /**
+ * Decreases the number of tasks that the given worker has applied.
+ *
+ * @param worker Worker which running tasks is decreased.
+ */
+ private decreaseWorkerRunningTasks (worker: Worker): void {
+ this.stepWorkerRunningTasks(worker, -1)
+ }
+
+ /**
+ * Steps the number of tasks that the given worker has applied.
+ *
+ * @param worker Worker which running tasks are stepped.
+ * @param step Number of running tasks step.
+ */
+ private stepWorkerRunningTasks (worker: Worker, step: number): void {
+ if (this.checkWorkerTasksUsage(worker) === true) {
+ const tasksUsage = this.workersTasksUsage.get(worker) as TasksUsage
+ tasksUsage.running = tasksUsage.running + step
+ this.workersTasksUsage.set(worker, tasksUsage)
+ }
+ }
+
+ /**
+ * Steps the number of tasks that the given worker has run.
+ *
+ * @param worker Worker which has run tasks.
+ * @param step Number of run tasks step.
+ */
+ private stepWorkerRunTasks (worker: Worker, step: number): void {
+ if (this.checkWorkerTasksUsage(worker) === true) {
+ const tasksUsage = this.workersTasksUsage.get(worker) as TasksUsage
+ tasksUsage.run = tasksUsage.run + step
+ this.workersTasksUsage.set(worker, tasksUsage)
+ }
+ }
+
+ /**
+ * Updates tasks runtime for the given worker.
+ *
+ * @param worker Worker which run the task.
+ * @param taskRunTime Worker task runtime.
+ */
+ private updateWorkerTasksRunTime (
+ worker: Worker,
+ taskRunTime: number | undefined
+ ): void {
+ if (
+ this.workerChoiceStrategyContext.getWorkerChoiceStrategy()
+ .requiredStatistics.runTime === true &&
+ this.checkWorkerTasksUsage(worker) === true
+ ) {
+ const tasksUsage = this.workersTasksUsage.get(worker) as TasksUsage
+ tasksUsage.runTime += taskRunTime ?? 0
+ if (tasksUsage.run !== 0) {
+ tasksUsage.avgRunTime = tasksUsage.runTime / tasksUsage.run
+ }
+ this.workersTasksUsage.set(worker, tasksUsage)
+ }
+ }
+
+ /**
+ * Checks if the given worker is registered in the workers tasks usage map.
+ *
+ * @param worker Worker to check.
+ * @returns `true` if the worker is registered in the workers tasks usage map. `false` otherwise.
+ */
+ private checkWorkerTasksUsage (worker: Worker): boolean {
+ const hasTasksUsage = this.workersTasksUsage.has(worker)
+ if (hasTasksUsage === false) {
+ throw new Error('Worker could not be found in workers tasks usage map')
+ }
+ return hasTasksUsage
+ }
+
+ /**
+ * Initializes tasks usage statistics.
+ *
+ * @param worker The worker.
+ */
+ private initWorkerTasksUsage (worker: Worker): void {
+ this.workersTasksUsage.set(worker, {
+ run: 0,
+ running: 0,
+ runTime: 0,
+ avgRunTime: 0
+ })
+ }
+
+ /**
+ * Removes worker tasks usage statistics.
+ *
+ * @param worker The worker.
+ */
+ private removeWorkerTasksUsage (worker: Worker): void {
+ this.workersTasksUsage.delete(worker)
+ }
+
+ /**
+ * Resets worker tasks usage statistics.
+ *
+ * @param worker The worker.
+ */
+ private resetWorkerTasksUsage (worker: Worker): void {
+ this.removeWorkerTasksUsage(worker)
+ this.initWorkerTasksUsage(worker)
}
}
repositories / poolifier.git / blobdiff