src/pools/worker-node.ts

   1 import { MessageChannel } from 'node:worker_threads'
   2 import { CircularArray } from '../circular-array'
   3 import { Queue } from '../queue'
   4 import type { Task } from '../utility-types'
   5 import { DEFAULT_TASK_NAME } from '../utils'
   6 import {
   7   type IWorker,
   8   type IWorkerNode,
   9   type WorkerInfo,
  10   type WorkerType,
  11   WorkerTypes,
  12   type WorkerUsage
  13 } from './worker'
  14
  15 /**
  16  * Worker node.
  17  *
  18  * @typeParam Worker - Type of worker.
  19  * @typeParam Data - Type of data sent to the worker. This can only be structured-cloneable data.
  20  */
  21 export class WorkerNode<Worker extends IWorker, Data = unknown>
  22 implements IWorkerNode<Worker, Data> {
  23   /** @inheritdoc */
  24   public readonly worker: Worker
  25   /** @inheritdoc */
  26   public readonly info: WorkerInfo
  27   /** @inheritdoc */
  28   public messageChannel?: MessageChannel
  29   /** @inheritdoc */
  30   public usage: WorkerUsage
  31   private readonly taskFunctionsUsage: Map<string, WorkerUsage>
  32   private readonly tasksQueue: Queue<Task<Data>>
  33   private readonly tasksQueueBackPressureSize: number
  34
  35   /**
  36    * Constructs a new worker node.
  37    *
  38    * @param worker - The worker.
  39    * @param workerType - The worker type.
  40    * @param poolMaxSize - The pool maximum size.
  41    */
  42   constructor (worker: Worker, workerType: WorkerType, poolMaxSize: number) {
  43     this.worker = worker
  44     this.info = this.initWorkerInfo(worker, workerType)
  45     if (workerType === WorkerTypes.thread) {
  46       this.messageChannel = new MessageChannel()
  47     }
  48     this.usage = this.initWorkerUsage()
  49     this.taskFunctionsUsage = new Map<string, WorkerUsage>()
  50     this.tasksQueue = new Queue<Task<Data>>()
  51     this.tasksQueueBackPressureSize = Math.pow(poolMaxSize, 2)
  52   }
  53
  54   /** @inheritdoc */
  55   public tasksQueueSize (): number {
  56     return this.tasksQueue.size
  57   }
  58
  59   /**
  60    * Tasks queue maximum size.
  61    *
  62    * @returns The tasks queue maximum size.
  63    */
  64   private tasksQueueMaxSize (): number {
  65     return this.tasksQueue.maxSize
  66   }
  67
  68   /** @inheritdoc */
  69   public enqueueTask (task: Task<Data>): number {
  70     return this.tasksQueue.enqueue(task)
  71   }
  72
  73   /** @inheritdoc */
  74   public dequeueTask (): Task<Data> | undefined {
  75     return this.tasksQueue.dequeue()
  76   }
  77
  78   /** @inheritdoc */
  79   public clearTasksQueue (): void {
  80     this.tasksQueue.clear()
  81   }
  82
  83   /** @inheritdoc */
  84   public hasBackPressure (): boolean {
  85     return this.tasksQueueSize() >= this.tasksQueueBackPressureSize
  86   }
  87
  88   /** @inheritdoc */
  89   public resetUsage (): void {
  90     this.usage = this.initWorkerUsage()
  91     this.taskFunctionsUsage.clear()
  92   }
  93
  94   /** @inheritdoc */
  95   public closeChannel (): void {
  96     if (this.messageChannel != null) {
  97       this.messageChannel?.port1.unref()
  98       this.messageChannel?.port2.unref()
  99       this.messageChannel?.port1.close()
 100       this.messageChannel?.port2.close()
 101       delete this.messageChannel
 102     }
 103   }
 104
 105   /** @inheritdoc */
 106   public getTaskFunctionWorkerUsage (name: string): WorkerUsage | undefined {
 107     if (!Array.isArray(this.info.taskFunctions)) {
 108       throw new Error(
 109         `Cannot get task function worker usage for task function name '${name}' when task function names list is not yet defined`
 110       )
 111     }
 112     if (
 113       Array.isArray(this.info.taskFunctions) &&
 114       this.info.taskFunctions.length < 3
 115     ) {
 116       throw new Error(
 117         `Cannot get task function worker usage for task function name '${name}' when task function names list has less than 3 elements`
 118       )
 119     }
 120     if (name === DEFAULT_TASK_NAME) {
 121       name = this.info.taskFunctions[1]
 122     }
 123     if (!this.taskFunctionsUsage.has(name)) {
 124       this.taskFunctionsUsage.set(name, this.initTaskFunctionWorkerUsage(name))
 125     }
 126     return this.taskFunctionsUsage.get(name)
 127   }
 128
 129   private initWorkerInfo (worker: Worker, workerType: WorkerType): WorkerInfo {
 130     return {
 131       id: this.getWorkerId(worker, workerType),
 132       type: workerType,
 133       dynamic: false,
 134       ready: false
 135     }
 136   }
 137
 138   private initWorkerUsage (): WorkerUsage {
 139     const getTasksQueueSize = (): number => {
 140       return this.tasksQueueSize()
 141     }
 142     const getTasksQueueMaxSize = (): number => {
 143       return this.tasksQueueMaxSize()
 144     }
 145     return {
 146       tasks: {
 147         executed: 0,
 148         executing: 0,
 149         get queued (): number {
 150           return getTasksQueueSize()
 151         },
 152         get maxQueued (): number {
 153           return getTasksQueueMaxSize()
 154         },
 155         failed: 0
 156       },
 157       runTime: {
 158         history: new CircularArray()
 159       },
 160       waitTime: {
 161         history: new CircularArray()
 162       },
 163       elu: {
 164         idle: {
 165           history: new CircularArray()
 166         },
 167         active: {
 168           history: new CircularArray()
 169         }
 170       }
 171     }
 172   }
 173
 174   private initTaskFunctionWorkerUsage (name: string): WorkerUsage {
 175     const getTaskQueueSize = (): number => {
 176       let taskQueueSize = 0
 177       for (const task of this.tasksQueue) {
 178         if (task.name === name) {
 179           ++taskQueueSize
 180         }
 181       }
 182       return taskQueueSize
 183     }
 184     return {
 185       tasks: {
 186         executed: 0,
 187         executing: 0,
 188         get queued (): number {
 189           return getTaskQueueSize()
 190         },
 191         failed: 0
 192       },
 193       runTime: {
 194         history: new CircularArray()
 195       },
 196       waitTime: {
 197         history: new CircularArray()
 198       },
 199       elu: {
 200         idle: {
 201           history: new CircularArray()
 202         },
 203         active: {
 204           history: new CircularArray()
 205         }
 206       }
 207     }
 208   }
 209
 210   /**
 211    * Gets the worker id.
 212    *
 213    * @param worker - The worker.
 214    * @param workerType - The worker type.
 215    * @returns The worker id.
 216    */
 217   private getWorkerId (
 218     worker: Worker,
 219     workerType: WorkerType
 220   ): number | undefined {
 221     if (workerType === WorkerTypes.thread) {
 222       return worker.threadId
 223     } else if (workerType === WorkerTypes.cluster) {
 224       return worker.id
 225     }
 226   }
 227 }