import { MessageChannel } from 'node:worker_threads'
import { CircularArray } from '../circular-array'
-import { Queue } from '../queue'
import type { Task } from '../utility-types'
+import {
+ DEFAULT_TASK_NAME,
+ EMPTY_FUNCTION,
+ exponentialDelay,
+ getWorkerId,
+ getWorkerType,
+ sleep
+} from '../utils'
+import { Deque } from '../deque'
import {
type IWorker,
type IWorkerNode,
type WorkerInfo,
+ type WorkerNodeEventCallback,
type WorkerType,
WorkerTypes,
type WorkerUsage
*/
export class WorkerNode<Worker extends IWorker, Data = unknown>
implements IWorkerNode<Worker, Data> {
+ /** @inheritdoc */
public readonly worker: Worker
+ /** @inheritdoc */
public readonly info: WorkerInfo
+ /** @inheritdoc */
public usage: WorkerUsage
- private readonly tasksUsage: Map<string, WorkerUsage>
- private readonly tasksQueue: Queue<Task<Data>>
+ /** @inheritdoc */
+ public messageChannel?: MessageChannel
+ /** @inheritdoc */
+ public tasksQueueBackPressureSize: number
+ /** @inheritdoc */
+ public onBackPressure?: WorkerNodeEventCallback
+ /** @inheritdoc */
+ public onEmptyQueue?: WorkerNodeEventCallback
+ private readonly tasksQueue: Deque<Task<Data>>
+ private onEmptyQueueCount: number
+ private readonly taskFunctionsUsage: Map<string, WorkerUsage>
/**
* Constructs a new worker node.
*
* @param worker - The worker.
- * @param workerType - The worker type.
+ * @param tasksQueueBackPressureSize - The tasks queue back pressure size.
*/
- constructor (worker: Worker, workerType: WorkerType) {
+ constructor (worker: Worker, tasksQueueBackPressureSize: number) {
+ this.checkWorkerNodeArguments(worker, tasksQueueBackPressureSize)
this.worker = worker
- this.info = this.initWorkerInfo(worker, workerType)
+ this.info = this.initWorkerInfo(worker)
this.usage = this.initWorkerUsage()
- this.tasksUsage = new Map<string, WorkerUsage>()
- this.tasksQueue = new Queue<Task<Data>>()
+ if (this.info.type === WorkerTypes.thread) {
+ this.messageChannel = new MessageChannel()
+ }
+ this.tasksQueueBackPressureSize = tasksQueueBackPressureSize
+ this.tasksQueue = new Deque<Task<Data>>()
+ this.onEmptyQueueCount = 0
+ this.taskFunctionsUsage = new Map<string, WorkerUsage>()
}
/** @inheritdoc */
return this.tasksQueue.size
}
- /**
- * Tasks queue maximum size.
- *
- * @returns The tasks queue maximum size.
- */
- private tasksQueueMaxSize (): number {
- return this.tasksQueue.maxSize
+ /** @inheritdoc */
+ public enqueueTask (task: Task<Data>): number {
+ const tasksQueueSize = this.tasksQueue.push(task)
+ if (this.onBackPressure != null && this.hasBackPressure()) {
+ this.onBackPressure(this.info.id as number)
+ }
+ return tasksQueueSize
}
/** @inheritdoc */
- public enqueueTask (task: Task<Data>): number {
- return this.tasksQueue.enqueue(task)
+ public unshiftTask (task: Task<Data>): number {
+ const tasksQueueSize = this.tasksQueue.unshift(task)
+ if (this.onBackPressure != null && this.hasBackPressure()) {
+ this.onBackPressure(this.info.id as number)
+ }
+ return tasksQueueSize
}
/** @inheritdoc */
public dequeueTask (): Task<Data> | undefined {
- return this.tasksQueue.dequeue()
+ const task = this.tasksQueue.shift()
+ if (this.onEmptyQueue != null && this.tasksQueue.size === 0) {
+ this.startOnEmptyQueue().catch(EMPTY_FUNCTION)
+ }
+ return task
+ }
+
+ /** @inheritdoc */
+ public popTask (): Task<Data> | undefined {
+ const task = this.tasksQueue.pop()
+ if (this.onEmptyQueue != null && this.tasksQueue.size === 0) {
+ this.startOnEmptyQueue().catch(EMPTY_FUNCTION)
+ }
+ return task
}
/** @inheritdoc */
this.tasksQueue.clear()
}
+ /** @inheritdoc */
+ public hasBackPressure (): boolean {
+ return this.tasksQueue.size >= this.tasksQueueBackPressureSize
+ }
+
/** @inheritdoc */
public resetUsage (): void {
this.usage = this.initWorkerUsage()
- this.tasksUsage.clear()
+ this.taskFunctionsUsage.clear()
}
/** @inheritdoc */
- public getTaskWorkerUsage (name: string): WorkerUsage | undefined {
- if (!this.tasksUsage.has(name)) {
- this.tasksUsage.set(name, this.initTaskWorkerUsage(name))
+ public closeChannel (): void {
+ if (this.messageChannel != null) {
+ this.messageChannel?.port1.unref()
+ this.messageChannel?.port2.unref()
+ this.messageChannel?.port1.close()
+ this.messageChannel?.port2.close()
+ delete this.messageChannel
+ }
+ }
+
+ /** @inheritdoc */
+ public getTaskFunctionWorkerUsage (name: string): WorkerUsage | undefined {
+ if (!Array.isArray(this.info.taskFunctions)) {
+ throw new Error(
+ `Cannot get task function worker usage for task function name '${name}' when task function names list is not yet defined`
+ )
+ }
+ if (
+ Array.isArray(this.info.taskFunctions) &&
+ this.info.taskFunctions.length < 3
+ ) {
+ throw new Error(
+ `Cannot get task function worker usage for task function name '${name}' when task function names list has less than 3 elements`
+ )
+ }
+ if (name === DEFAULT_TASK_NAME) {
+ name = this.info.taskFunctions[1]
+ }
+ if (!this.taskFunctionsUsage.has(name)) {
+ this.taskFunctionsUsage.set(name, this.initTaskFunctionWorkerUsage(name))
}
- return this.tasksUsage.get(name)
+ return this.taskFunctionsUsage.get(name)
}
- private initWorkerInfo (worker: Worker, workerType: WorkerType): WorkerInfo {
+ private async startOnEmptyQueue (): Promise<void> {
+ if (
+ this.onEmptyQueueCount > 0 &&
+ (this.usage.tasks.executing > 0 || this.tasksQueue.size > 0)
+ ) {
+ this.onEmptyQueueCount = 0
+ return
+ }
+ (this.onEmptyQueue as WorkerNodeEventCallback)(this.info.id as number)
+ ++this.onEmptyQueueCount
+ await sleep(exponentialDelay(this.onEmptyQueueCount))
+ await this.startOnEmptyQueue()
+ }
+
+ private initWorkerInfo (worker: Worker): WorkerInfo {
return {
- id: this.getWorkerId(worker, workerType),
- type: workerType,
+ id: getWorkerId(worker),
+ type: getWorkerType(worker) as WorkerType,
dynamic: false,
- ready: false,
- ...(workerType === WorkerTypes.thread && {
- messageChannel: new MessageChannel()
- })
+ ready: false
}
}
private initWorkerUsage (): WorkerUsage {
const getTasksQueueSize = (): number => {
- return this.tasksQueueSize()
+ return this.tasksQueue.size
}
const getTasksQueueMaxSize = (): number => {
- return this.tasksQueueMaxSize()
+ return this.tasksQueue.maxSize
}
return {
tasks: {
get maxQueued (): number {
return getTasksQueueMaxSize()
},
+ stolen: 0,
failed: 0
},
runTime: {
}
}
- private initTaskWorkerUsage (name: string): WorkerUsage {
- const getTaskQueueSize = (): number => {
- let taskQueueSize = 0
+ private initTaskFunctionWorkerUsage (name: string): WorkerUsage {
+ const getTaskFunctionQueueSize = (): number => {
+ let taskFunctionQueueSize = 0
for (const task of this.tasksQueue) {
- if (task.name === name) {
- ++taskQueueSize
+ if (
+ (task.name === DEFAULT_TASK_NAME &&
+ name === (this.info.taskFunctions as string[])[1]) ||
+ (task.name !== DEFAULT_TASK_NAME && name === task.name)
+ ) {
+ ++taskFunctionQueueSize
}
}
- return taskQueueSize
+ return taskFunctionQueueSize
}
return {
tasks: {
executed: 0,
executing: 0,
get queued (): number {
- return getTaskQueueSize()
+ return getTaskFunctionQueueSize()
},
+ stolen: 0,
failed: 0
},
runTime: {
}
}
- /**
- * Gets the worker id.
- *
- * @param worker - The worker.
- * @param workerType - The worker type.
- * @returns The worker id.
- */
- private getWorkerId (
+ private checkWorkerNodeArguments (
worker: Worker,
- workerType: WorkerType
- ): number | undefined {
- if (workerType === WorkerTypes.thread) {
- return worker.threadId
- } else if (workerType === WorkerTypes.cluster) {
- return worker.id
+ tasksQueueBackPressureSize: number
+ ): void {
+ if (worker == null) {
+ throw new TypeError('Cannot construct a worker node without a worker')
+ }
+ if (tasksQueueBackPressureSize == null) {
+ throw new TypeError(
+ 'Cannot construct a worker node without a tasks queue back pressure size'
+ )
+ }
+ if (!Number.isSafeInteger(tasksQueueBackPressureSize)) {
+ throw new TypeError(
+ 'Cannot construct a worker node with a tasks queue back pressure size that is not an integer'
+ )
+ }
+ if (tasksQueueBackPressureSize <= 0) {
+ throw new RangeError(
+ 'Cannot construct a worker node with a tasks queue back pressure size that is not a positive integer'
+ )
}
}
}