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 tasksUsage: Map<string, WorkerUsage>
  32   private readonly tasksQueue: Queue<Task<Data>>
  33   private readonly tasksQueueBackPressureMaxSize: 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.tasksUsage = new Map<string, WorkerUsage>()
  50     this.tasksQueue = new Queue<Task<Data>>()
  51     this.tasksQueueBackPressureMaxSize = 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.tasksQueueBackPressureMaxSize
  86   }
  87
  88   /** @inheritdoc */
  89   public resetUsage (): void {
  90     this.usage = this.initWorkerUsage()
  91     this.tasksUsage.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 getTaskWorkerUsage (name: string): WorkerUsage | undefined {
 107     if (!Array.isArray(this.info.taskFunctions)) {
 108       throw new Error(
 109         `Cannot get task worker usage for task function name '${name}' when task function names list is not yet defined`
 110       )
 111     }
 112     if (
 113       name === DEFAULT_TASK_NAME &&
 114       Array.isArray(this.info.taskFunctions) &&
 115       this.info.taskFunctions.length > 1
 116     ) {
 117       name = this.info.taskFunctions[1]
 118     }
 119     if (!this.tasksUsage.has(name)) {
 120       this.tasksUsage.set(name, this.initTaskWorkerUsage(name))
 121     }
 122     return this.tasksUsage.get(name)
 123   }
 124
 125   private initWorkerInfo (worker: Worker, workerType: WorkerType): WorkerInfo {
 126     return {
 127       id: this.getWorkerId(worker, workerType),
 128       type: workerType,
 129       dynamic: false,
 130       ready: false
 131     }
 132   }
 133
 134   private initWorkerUsage (): WorkerUsage {
 135     const getTasksQueueSize = (): number => {
 136       return this.tasksQueueSize()
 137     }
 138     const getTasksQueueMaxSize = (): number => {
 139       return this.tasksQueueMaxSize()
 140     }
 141     return {
 142       tasks: {
 143         executed: 0,
 144         executing: 0,
 145         get queued (): number {
 146           return getTasksQueueSize()
 147         },
 148         get maxQueued (): number {
 149           return getTasksQueueMaxSize()
 150         },
 151         failed: 0
 152       },
 153       runTime: {
 154         history: new CircularArray()
 155       },
 156       waitTime: {
 157         history: new CircularArray()
 158       },
 159       elu: {
 160         idle: {
 161           history: new CircularArray()
 162         },
 163         active: {
 164           history: new CircularArray()
 165         }
 166       }
 167     }
 168   }
 169
 170   private initTaskWorkerUsage (name: string): WorkerUsage {
 171     const getTaskQueueSize = (): number => {
 172       let taskQueueSize = 0
 173       for (const task of this.tasksQueue) {
 174         if (task.name === name) {
 175           ++taskQueueSize
 176         }
 177       }
 178       return taskQueueSize
 179     }
 180     return {
 181       tasks: {
 182         executed: 0,
 183         executing: 0,
 184         get queued (): number {
 185           return getTaskQueueSize()
 186         },
 187         failed: 0
 188       },
 189       runTime: {
 190         history: new CircularArray()
 191       },
 192       waitTime: {
 193         history: new CircularArray()
 194       },
 195       elu: {
 196         idle: {
 197           history: new CircularArray()
 198         },
 199         active: {
 200           history: new CircularArray()
 201         }
 202       }
 203     }
 204   }
 205
 206   /**
 207    * Gets the worker id.
 208    *
 209    * @param worker - The worker.
 210    * @param workerType - The worker type.
 211    * @returns The worker id.
 212    */
 213   private getWorkerId (
 214     worker: Worker,
 215     workerType: WorkerType
 216   ): number | undefined {
 217     if (workerType === WorkerTypes.thread) {
 218       return worker.threadId
 219     } else if (workerType === WorkerTypes.cluster) {
 220       return worker.id
 221     }
 222   }
 223 }