| 1 | import { randomUUID } from 'node:crypto' |
| 2 | import { performance } from 'node:perf_hooks' |
| 3 | import { existsSync } from 'node:fs' |
| 4 | import { type TransferListItem } from 'node:worker_threads' |
| 5 | import type { |
| 6 | MessageValue, |
| 7 | PromiseResponseWrapper, |
| 8 | Task |
| 9 | } from '../utility-types' |
| 10 | import { |
| 11 | DEFAULT_TASK_NAME, |
| 12 | DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS, |
| 13 | EMPTY_FUNCTION, |
| 14 | average, |
| 15 | isKillBehavior, |
| 16 | isPlainObject, |
| 17 | max, |
| 18 | median, |
| 19 | min, |
| 20 | round, |
| 21 | updateMeasurementStatistics |
| 22 | } from '../utils' |
| 23 | import { KillBehaviors } from '../worker/worker-options' |
| 24 | import type { TaskFunction } from '../worker/task-functions' |
| 25 | import { |
| 26 | type IPool, |
| 27 | PoolEmitter, |
| 28 | PoolEvents, |
| 29 | type PoolInfo, |
| 30 | type PoolOptions, |
| 31 | type PoolType, |
| 32 | PoolTypes, |
| 33 | type TasksQueueOptions |
| 34 | } from './pool' |
| 35 | import type { |
| 36 | IWorker, |
| 37 | IWorkerNode, |
| 38 | WorkerInfo, |
| 39 | WorkerType, |
| 40 | WorkerUsage |
| 41 | } from './worker' |
| 42 | import { |
| 43 | type MeasurementStatisticsRequirements, |
| 44 | Measurements, |
| 45 | WorkerChoiceStrategies, |
| 46 | type WorkerChoiceStrategy, |
| 47 | type WorkerChoiceStrategyOptions |
| 48 | } from './selection-strategies/selection-strategies-types' |
| 49 | import { WorkerChoiceStrategyContext } from './selection-strategies/worker-choice-strategy-context' |
| 50 | import { version } from './version' |
| 51 | import { WorkerNode } from './worker-node' |
| 52 | |
| 53 | /** |
| 54 | * Base class that implements some shared logic for all poolifier pools. |
| 55 | * |
| 56 | * @typeParam Worker - Type of worker which manages this pool. |
| 57 | * @typeParam Data - Type of data sent to the worker. This can only be structured-cloneable data. |
| 58 | * @typeParam Response - Type of execution response. This can only be structured-cloneable data. |
| 59 | */ |
| 60 | export abstract class AbstractPool< |
| 61 | Worker extends IWorker, |
| 62 | Data = unknown, |
| 63 | Response = unknown |
| 64 | > implements IPool<Worker, Data, Response> { |
| 65 | /** @inheritDoc */ |
| 66 | public readonly workerNodes: Array<IWorkerNode<Worker, Data>> = [] |
| 67 | |
| 68 | /** @inheritDoc */ |
| 69 | public readonly emitter?: PoolEmitter |
| 70 | |
| 71 | /** |
| 72 | * The task execution response promise map: |
| 73 | * - `key`: The message id of each submitted task. |
| 74 | * - `value`: An object that contains the worker, the execution response promise resolve and reject callbacks. |
| 75 | * |
| 76 | * When we receive a message from the worker, we get a map entry with the promise resolve/reject bound to the message id. |
| 77 | */ |
| 78 | protected promiseResponseMap: Map<string, PromiseResponseWrapper<Response>> = |
| 79 | new Map<string, PromiseResponseWrapper<Response>>() |
| 80 | |
| 81 | /** |
| 82 | * Worker choice strategy context referencing a worker choice algorithm implementation. |
| 83 | */ |
| 84 | protected workerChoiceStrategyContext: WorkerChoiceStrategyContext< |
| 85 | Worker, |
| 86 | Data, |
| 87 | Response |
| 88 | > |
| 89 | |
| 90 | /** |
| 91 | * Dynamic pool maximum size property placeholder. |
| 92 | */ |
| 93 | protected readonly max?: number |
| 94 | |
| 95 | /** |
| 96 | * The task functions added at runtime map: |
| 97 | * - `key`: The task function name. |
| 98 | * - `value`: The task function itself. |
| 99 | */ |
| 100 | private readonly taskFunctions: Map<string, TaskFunction<Data, Response>> |
| 101 | |
| 102 | /** |
| 103 | * Whether the pool is started or not. |
| 104 | */ |
| 105 | private started: boolean |
| 106 | /** |
| 107 | * Whether the pool is starting or not. |
| 108 | */ |
| 109 | private starting: boolean |
| 110 | /** |
| 111 | * The start timestamp of the pool. |
| 112 | */ |
| 113 | private readonly startTimestamp |
| 114 | |
| 115 | /** |
| 116 | * Constructs a new poolifier pool. |
| 117 | * |
| 118 | * @param numberOfWorkers - Number of workers that this pool should manage. |
| 119 | * @param filePath - Path to the worker file. |
| 120 | * @param opts - Options for the pool. |
| 121 | */ |
| 122 | public constructor ( |
| 123 | protected readonly numberOfWorkers: number, |
| 124 | protected readonly filePath: string, |
| 125 | protected readonly opts: PoolOptions<Worker> |
| 126 | ) { |
| 127 | if (!this.isMain()) { |
| 128 | throw new Error( |
| 129 | 'Cannot start a pool from a worker with the same type as the pool' |
| 130 | ) |
| 131 | } |
| 132 | this.checkNumberOfWorkers(this.numberOfWorkers) |
| 133 | this.checkFilePath(this.filePath) |
| 134 | this.checkPoolOptions(this.opts) |
| 135 | |
| 136 | this.chooseWorkerNode = this.chooseWorkerNode.bind(this) |
| 137 | this.executeTask = this.executeTask.bind(this) |
| 138 | this.enqueueTask = this.enqueueTask.bind(this) |
| 139 | |
| 140 | if (this.opts.enableEvents === true) { |
| 141 | this.emitter = new PoolEmitter() |
| 142 | } |
| 143 | this.workerChoiceStrategyContext = new WorkerChoiceStrategyContext< |
| 144 | Worker, |
| 145 | Data, |
| 146 | Response |
| 147 | >( |
| 148 | this, |
| 149 | this.opts.workerChoiceStrategy, |
| 150 | this.opts.workerChoiceStrategyOptions |
| 151 | ) |
| 152 | |
| 153 | this.setupHook() |
| 154 | |
| 155 | this.taskFunctions = new Map<string, TaskFunction<Data, Response>>() |
| 156 | |
| 157 | this.started = false |
| 158 | this.starting = false |
| 159 | if (this.opts.startWorkers === true) { |
| 160 | this.start() |
| 161 | } |
| 162 | |
| 163 | this.startTimestamp = performance.now() |
| 164 | } |
| 165 | |
| 166 | private checkFilePath (filePath: string): void { |
| 167 | if ( |
| 168 | filePath == null || |
| 169 | typeof filePath !== 'string' || |
| 170 | (typeof filePath === 'string' && filePath.trim().length === 0) |
| 171 | ) { |
| 172 | throw new Error('Please specify a file with a worker implementation') |
| 173 | } |
| 174 | if (!existsSync(filePath)) { |
| 175 | throw new Error(`Cannot find the worker file '${filePath}'`) |
| 176 | } |
| 177 | } |
| 178 | |
| 179 | private checkNumberOfWorkers (numberOfWorkers: number): void { |
| 180 | if (numberOfWorkers == null) { |
| 181 | throw new Error( |
| 182 | 'Cannot instantiate a pool without specifying the number of workers' |
| 183 | ) |
| 184 | } else if (!Number.isSafeInteger(numberOfWorkers)) { |
| 185 | throw new TypeError( |
| 186 | 'Cannot instantiate a pool with a non safe integer number of workers' |
| 187 | ) |
| 188 | } else if (numberOfWorkers < 0) { |
| 189 | throw new RangeError( |
| 190 | 'Cannot instantiate a pool with a negative number of workers' |
| 191 | ) |
| 192 | } else if (this.type === PoolTypes.fixed && numberOfWorkers === 0) { |
| 193 | throw new RangeError('Cannot instantiate a fixed pool with zero worker') |
| 194 | } |
| 195 | } |
| 196 | |
| 197 | protected checkDynamicPoolSize (min: number, max: number): void { |
| 198 | if (this.type === PoolTypes.dynamic) { |
| 199 | if (max == null) { |
| 200 | throw new TypeError( |
| 201 | 'Cannot instantiate a dynamic pool without specifying the maximum pool size' |
| 202 | ) |
| 203 | } else if (!Number.isSafeInteger(max)) { |
| 204 | throw new TypeError( |
| 205 | 'Cannot instantiate a dynamic pool with a non safe integer maximum pool size' |
| 206 | ) |
| 207 | } else if (min > max) { |
| 208 | throw new RangeError( |
| 209 | 'Cannot instantiate a dynamic pool with a maximum pool size inferior to the minimum pool size' |
| 210 | ) |
| 211 | } else if (max === 0) { |
| 212 | throw new RangeError( |
| 213 | 'Cannot instantiate a dynamic pool with a maximum pool size equal to zero' |
| 214 | ) |
| 215 | } else if (min === max) { |
| 216 | throw new RangeError( |
| 217 | 'Cannot instantiate a dynamic pool with a minimum pool size equal to the maximum pool size. Use a fixed pool instead' |
| 218 | ) |
| 219 | } |
| 220 | } |
| 221 | } |
| 222 | |
| 223 | private checkPoolOptions (opts: PoolOptions<Worker>): void { |
| 224 | if (isPlainObject(opts)) { |
| 225 | this.opts.startWorkers = opts.startWorkers ?? true |
| 226 | this.opts.workerChoiceStrategy = |
| 227 | opts.workerChoiceStrategy ?? WorkerChoiceStrategies.ROUND_ROBIN |
| 228 | this.checkValidWorkerChoiceStrategy(this.opts.workerChoiceStrategy) |
| 229 | this.opts.workerChoiceStrategyOptions = { |
| 230 | ...DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS, |
| 231 | ...opts.workerChoiceStrategyOptions |
| 232 | } |
| 233 | this.checkValidWorkerChoiceStrategyOptions( |
| 234 | this.opts.workerChoiceStrategyOptions |
| 235 | ) |
| 236 | this.opts.restartWorkerOnError = opts.restartWorkerOnError ?? true |
| 237 | this.opts.enableEvents = opts.enableEvents ?? true |
| 238 | this.opts.enableTasksQueue = opts.enableTasksQueue ?? false |
| 239 | if (this.opts.enableTasksQueue) { |
| 240 | this.checkValidTasksQueueOptions( |
| 241 | opts.tasksQueueOptions as TasksQueueOptions |
| 242 | ) |
| 243 | this.opts.tasksQueueOptions = this.buildTasksQueueOptions( |
| 244 | opts.tasksQueueOptions as TasksQueueOptions |
| 245 | ) |
| 246 | } |
| 247 | } else { |
| 248 | throw new TypeError('Invalid pool options: must be a plain object') |
| 249 | } |
| 250 | } |
| 251 | |
| 252 | private checkValidWorkerChoiceStrategy ( |
| 253 | workerChoiceStrategy: WorkerChoiceStrategy |
| 254 | ): void { |
| 255 | if (!Object.values(WorkerChoiceStrategies).includes(workerChoiceStrategy)) { |
| 256 | throw new Error( |
| 257 | `Invalid worker choice strategy '${workerChoiceStrategy}'` |
| 258 | ) |
| 259 | } |
| 260 | } |
| 261 | |
| 262 | private checkValidWorkerChoiceStrategyOptions ( |
| 263 | workerChoiceStrategyOptions: WorkerChoiceStrategyOptions |
| 264 | ): void { |
| 265 | if (!isPlainObject(workerChoiceStrategyOptions)) { |
| 266 | throw new TypeError( |
| 267 | 'Invalid worker choice strategy options: must be a plain object' |
| 268 | ) |
| 269 | } |
| 270 | if ( |
| 271 | workerChoiceStrategyOptions.retries != null && |
| 272 | !Number.isSafeInteger(workerChoiceStrategyOptions.retries) |
| 273 | ) { |
| 274 | throw new TypeError( |
| 275 | 'Invalid worker choice strategy options: retries must be an integer' |
| 276 | ) |
| 277 | } |
| 278 | if ( |
| 279 | workerChoiceStrategyOptions.retries != null && |
| 280 | workerChoiceStrategyOptions.retries < 0 |
| 281 | ) { |
| 282 | throw new RangeError( |
| 283 | `Invalid worker choice strategy options: retries '${workerChoiceStrategyOptions.retries}' must be greater or equal than zero` |
| 284 | ) |
| 285 | } |
| 286 | if ( |
| 287 | workerChoiceStrategyOptions.weights != null && |
| 288 | Object.keys(workerChoiceStrategyOptions.weights).length !== this.maxSize |
| 289 | ) { |
| 290 | throw new Error( |
| 291 | 'Invalid worker choice strategy options: must have a weight for each worker node' |
| 292 | ) |
| 293 | } |
| 294 | if ( |
| 295 | workerChoiceStrategyOptions.measurement != null && |
| 296 | !Object.values(Measurements).includes( |
| 297 | workerChoiceStrategyOptions.measurement |
| 298 | ) |
| 299 | ) { |
| 300 | throw new Error( |
| 301 | `Invalid worker choice strategy options: invalid measurement '${workerChoiceStrategyOptions.measurement}'` |
| 302 | ) |
| 303 | } |
| 304 | } |
| 305 | |
| 306 | private checkValidTasksQueueOptions ( |
| 307 | tasksQueueOptions: TasksQueueOptions |
| 308 | ): void { |
| 309 | if (tasksQueueOptions != null && !isPlainObject(tasksQueueOptions)) { |
| 310 | throw new TypeError('Invalid tasks queue options: must be a plain object') |
| 311 | } |
| 312 | if ( |
| 313 | tasksQueueOptions?.concurrency != null && |
| 314 | !Number.isSafeInteger(tasksQueueOptions?.concurrency) |
| 315 | ) { |
| 316 | throw new TypeError( |
| 317 | 'Invalid worker node tasks concurrency: must be an integer' |
| 318 | ) |
| 319 | } |
| 320 | if ( |
| 321 | tasksQueueOptions?.concurrency != null && |
| 322 | tasksQueueOptions?.concurrency <= 0 |
| 323 | ) { |
| 324 | throw new RangeError( |
| 325 | `Invalid worker node tasks concurrency: ${tasksQueueOptions?.concurrency} is a negative integer or zero` |
| 326 | ) |
| 327 | } |
| 328 | if ( |
| 329 | tasksQueueOptions?.size != null && |
| 330 | !Number.isSafeInteger(tasksQueueOptions?.size) |
| 331 | ) { |
| 332 | throw new TypeError( |
| 333 | 'Invalid worker node tasks queue size: must be an integer' |
| 334 | ) |
| 335 | } |
| 336 | if (tasksQueueOptions?.size != null && tasksQueueOptions?.size <= 0) { |
| 337 | throw new RangeError( |
| 338 | `Invalid worker node tasks queue size: ${tasksQueueOptions?.size} is a negative integer or zero` |
| 339 | ) |
| 340 | } |
| 341 | } |
| 342 | |
| 343 | /** @inheritDoc */ |
| 344 | public get info (): PoolInfo { |
| 345 | return { |
| 346 | version, |
| 347 | type: this.type, |
| 348 | worker: this.worker, |
| 349 | started: this.started, |
| 350 | ready: this.ready, |
| 351 | strategy: this.opts.workerChoiceStrategy as WorkerChoiceStrategy, |
| 352 | minSize: this.minSize, |
| 353 | maxSize: this.maxSize, |
| 354 | ...(this.workerChoiceStrategyContext.getTaskStatisticsRequirements() |
| 355 | .runTime.aggregate && |
| 356 | this.workerChoiceStrategyContext.getTaskStatisticsRequirements() |
| 357 | .waitTime.aggregate && { utilization: round(this.utilization) }), |
| 358 | workerNodes: this.workerNodes.length, |
| 359 | idleWorkerNodes: this.workerNodes.reduce( |
| 360 | (accumulator, workerNode) => |
| 361 | workerNode.usage.tasks.executing === 0 |
| 362 | ? accumulator + 1 |
| 363 | : accumulator, |
| 364 | 0 |
| 365 | ), |
| 366 | busyWorkerNodes: this.workerNodes.reduce( |
| 367 | (accumulator, workerNode) => |
| 368 | workerNode.usage.tasks.executing > 0 ? accumulator + 1 : accumulator, |
| 369 | 0 |
| 370 | ), |
| 371 | executedTasks: this.workerNodes.reduce( |
| 372 | (accumulator, workerNode) => |
| 373 | accumulator + workerNode.usage.tasks.executed, |
| 374 | 0 |
| 375 | ), |
| 376 | executingTasks: this.workerNodes.reduce( |
| 377 | (accumulator, workerNode) => |
| 378 | accumulator + workerNode.usage.tasks.executing, |
| 379 | 0 |
| 380 | ), |
| 381 | ...(this.opts.enableTasksQueue === true && { |
| 382 | queuedTasks: this.workerNodes.reduce( |
| 383 | (accumulator, workerNode) => |
| 384 | accumulator + workerNode.usage.tasks.queued, |
| 385 | 0 |
| 386 | ) |
| 387 | }), |
| 388 | ...(this.opts.enableTasksQueue === true && { |
| 389 | maxQueuedTasks: this.workerNodes.reduce( |
| 390 | (accumulator, workerNode) => |
| 391 | accumulator + (workerNode.usage.tasks?.maxQueued ?? 0), |
| 392 | 0 |
| 393 | ) |
| 394 | }), |
| 395 | ...(this.opts.enableTasksQueue === true && { |
| 396 | backPressure: this.hasBackPressure() |
| 397 | }), |
| 398 | ...(this.opts.enableTasksQueue === true && { |
| 399 | stolenTasks: this.workerNodes.reduce( |
| 400 | (accumulator, workerNode) => |
| 401 | accumulator + workerNode.usage.tasks.stolen, |
| 402 | 0 |
| 403 | ) |
| 404 | }), |
| 405 | failedTasks: this.workerNodes.reduce( |
| 406 | (accumulator, workerNode) => |
| 407 | accumulator + workerNode.usage.tasks.failed, |
| 408 | 0 |
| 409 | ), |
| 410 | ...(this.workerChoiceStrategyContext.getTaskStatisticsRequirements() |
| 411 | .runTime.aggregate && { |
| 412 | runTime: { |
| 413 | minimum: round( |
| 414 | min( |
| 415 | ...this.workerNodes.map( |
| 416 | workerNode => workerNode.usage.runTime?.minimum ?? Infinity |
| 417 | ) |
| 418 | ) |
| 419 | ), |
| 420 | maximum: round( |
| 421 | max( |
| 422 | ...this.workerNodes.map( |
| 423 | workerNode => workerNode.usage.runTime?.maximum ?? -Infinity |
| 424 | ) |
| 425 | ) |
| 426 | ), |
| 427 | ...(this.workerChoiceStrategyContext.getTaskStatisticsRequirements() |
| 428 | .runTime.average && { |
| 429 | average: round( |
| 430 | average( |
| 431 | this.workerNodes.reduce<number[]>( |
| 432 | (accumulator, workerNode) => |
| 433 | accumulator.concat(workerNode.usage.runTime.history), |
| 434 | [] |
| 435 | ) |
| 436 | ) |
| 437 | ) |
| 438 | }), |
| 439 | ...(this.workerChoiceStrategyContext.getTaskStatisticsRequirements() |
| 440 | .runTime.median && { |
| 441 | median: round( |
| 442 | median( |
| 443 | this.workerNodes.reduce<number[]>( |
| 444 | (accumulator, workerNode) => |
| 445 | accumulator.concat(workerNode.usage.runTime.history), |
| 446 | [] |
| 447 | ) |
| 448 | ) |
| 449 | ) |
| 450 | }) |
| 451 | } |
| 452 | }), |
| 453 | ...(this.workerChoiceStrategyContext.getTaskStatisticsRequirements() |
| 454 | .waitTime.aggregate && { |
| 455 | waitTime: { |
| 456 | minimum: round( |
| 457 | min( |
| 458 | ...this.workerNodes.map( |
| 459 | workerNode => workerNode.usage.waitTime?.minimum ?? Infinity |
| 460 | ) |
| 461 | ) |
| 462 | ), |
| 463 | maximum: round( |
| 464 | max( |
| 465 | ...this.workerNodes.map( |
| 466 | workerNode => workerNode.usage.waitTime?.maximum ?? -Infinity |
| 467 | ) |
| 468 | ) |
| 469 | ), |
| 470 | ...(this.workerChoiceStrategyContext.getTaskStatisticsRequirements() |
| 471 | .waitTime.average && { |
| 472 | average: round( |
| 473 | average( |
| 474 | this.workerNodes.reduce<number[]>( |
| 475 | (accumulator, workerNode) => |
| 476 | accumulator.concat(workerNode.usage.waitTime.history), |
| 477 | [] |
| 478 | ) |
| 479 | ) |
| 480 | ) |
| 481 | }), |
| 482 | ...(this.workerChoiceStrategyContext.getTaskStatisticsRequirements() |
| 483 | .waitTime.median && { |
| 484 | median: round( |
| 485 | median( |
| 486 | this.workerNodes.reduce<number[]>( |
| 487 | (accumulator, workerNode) => |
| 488 | accumulator.concat(workerNode.usage.waitTime.history), |
| 489 | [] |
| 490 | ) |
| 491 | ) |
| 492 | ) |
| 493 | }) |
| 494 | } |
| 495 | }) |
| 496 | } |
| 497 | } |
| 498 | |
| 499 | /** |
| 500 | * The pool readiness boolean status. |
| 501 | */ |
| 502 | private get ready (): boolean { |
| 503 | return ( |
| 504 | this.workerNodes.reduce( |
| 505 | (accumulator, workerNode) => |
| 506 | !workerNode.info.dynamic && workerNode.info.ready |
| 507 | ? accumulator + 1 |
| 508 | : accumulator, |
| 509 | 0 |
| 510 | ) >= this.minSize |
| 511 | ) |
| 512 | } |
| 513 | |
| 514 | /** |
| 515 | * The approximate pool utilization. |
| 516 | * |
| 517 | * @returns The pool utilization. |
| 518 | */ |
| 519 | private get utilization (): number { |
| 520 | const poolTimeCapacity = |
| 521 | (performance.now() - this.startTimestamp) * this.maxSize |
| 522 | const totalTasksRunTime = this.workerNodes.reduce( |
| 523 | (accumulator, workerNode) => |
| 524 | accumulator + (workerNode.usage.runTime?.aggregate ?? 0), |
| 525 | 0 |
| 526 | ) |
| 527 | const totalTasksWaitTime = this.workerNodes.reduce( |
| 528 | (accumulator, workerNode) => |
| 529 | accumulator + (workerNode.usage.waitTime?.aggregate ?? 0), |
| 530 | 0 |
| 531 | ) |
| 532 | return (totalTasksRunTime + totalTasksWaitTime) / poolTimeCapacity |
| 533 | } |
| 534 | |
| 535 | /** |
| 536 | * The pool type. |
| 537 | * |
| 538 | * If it is `'dynamic'`, it provides the `max` property. |
| 539 | */ |
| 540 | protected abstract get type (): PoolType |
| 541 | |
| 542 | /** |
| 543 | * The worker type. |
| 544 | */ |
| 545 | protected abstract get worker (): WorkerType |
| 546 | |
| 547 | /** |
| 548 | * The pool minimum size. |
| 549 | */ |
| 550 | protected get minSize (): number { |
| 551 | return this.numberOfWorkers |
| 552 | } |
| 553 | |
| 554 | /** |
| 555 | * The pool maximum size. |
| 556 | */ |
| 557 | protected get maxSize (): number { |
| 558 | return this.max ?? this.numberOfWorkers |
| 559 | } |
| 560 | |
| 561 | /** |
| 562 | * Checks if the worker id sent in the received message from a worker is valid. |
| 563 | * |
| 564 | * @param message - The received message. |
| 565 | * @throws {@link https://nodejs.org/api/errors.html#class-error} If the worker id is invalid. |
| 566 | */ |
| 567 | private checkMessageWorkerId (message: MessageValue<Response>): void { |
| 568 | if (message.workerId == null) { |
| 569 | throw new Error('Worker message received without worker id') |
| 570 | } else if ( |
| 571 | message.workerId != null && |
| 572 | this.getWorkerNodeKeyByWorkerId(message.workerId) === -1 |
| 573 | ) { |
| 574 | throw new Error( |
| 575 | `Worker message received from unknown worker '${message.workerId}'` |
| 576 | ) |
| 577 | } |
| 578 | } |
| 579 | |
| 580 | /** |
| 581 | * Gets the given worker its worker node key. |
| 582 | * |
| 583 | * @param worker - The worker. |
| 584 | * @returns The worker node key if found in the pool worker nodes, `-1` otherwise. |
| 585 | */ |
| 586 | private getWorkerNodeKeyByWorker (worker: Worker): number { |
| 587 | return this.workerNodes.findIndex( |
| 588 | workerNode => workerNode.worker === worker |
| 589 | ) |
| 590 | } |
| 591 | |
| 592 | /** |
| 593 | * Gets the worker node key given its worker id. |
| 594 | * |
| 595 | * @param workerId - The worker id. |
| 596 | * @returns The worker node key if the worker id is found in the pool worker nodes, `-1` otherwise. |
| 597 | */ |
| 598 | private getWorkerNodeKeyByWorkerId (workerId: number | undefined): number { |
| 599 | return this.workerNodes.findIndex( |
| 600 | workerNode => workerNode.info.id === workerId |
| 601 | ) |
| 602 | } |
| 603 | |
| 604 | /** @inheritDoc */ |
| 605 | public setWorkerChoiceStrategy ( |
| 606 | workerChoiceStrategy: WorkerChoiceStrategy, |
| 607 | workerChoiceStrategyOptions?: WorkerChoiceStrategyOptions |
| 608 | ): void { |
| 609 | this.checkValidWorkerChoiceStrategy(workerChoiceStrategy) |
| 610 | this.opts.workerChoiceStrategy = workerChoiceStrategy |
| 611 | this.workerChoiceStrategyContext.setWorkerChoiceStrategy( |
| 612 | this.opts.workerChoiceStrategy |
| 613 | ) |
| 614 | if (workerChoiceStrategyOptions != null) { |
| 615 | this.setWorkerChoiceStrategyOptions(workerChoiceStrategyOptions) |
| 616 | } |
| 617 | for (const [workerNodeKey, workerNode] of this.workerNodes.entries()) { |
| 618 | workerNode.resetUsage() |
| 619 | this.sendStatisticsMessageToWorker(workerNodeKey) |
| 620 | } |
| 621 | } |
| 622 | |
| 623 | /** @inheritDoc */ |
| 624 | public setWorkerChoiceStrategyOptions ( |
| 625 | workerChoiceStrategyOptions: WorkerChoiceStrategyOptions |
| 626 | ): void { |
| 627 | this.checkValidWorkerChoiceStrategyOptions(workerChoiceStrategyOptions) |
| 628 | this.opts.workerChoiceStrategyOptions = { |
| 629 | ...DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS, |
| 630 | ...workerChoiceStrategyOptions |
| 631 | } |
| 632 | this.workerChoiceStrategyContext.setOptions( |
| 633 | this.opts.workerChoiceStrategyOptions |
| 634 | ) |
| 635 | } |
| 636 | |
| 637 | /** @inheritDoc */ |
| 638 | public enableTasksQueue ( |
| 639 | enable: boolean, |
| 640 | tasksQueueOptions?: TasksQueueOptions |
| 641 | ): void { |
| 642 | if (this.opts.enableTasksQueue === true && !enable) { |
| 643 | this.flushTasksQueues() |
| 644 | } |
| 645 | this.opts.enableTasksQueue = enable |
| 646 | this.setTasksQueueOptions(tasksQueueOptions as TasksQueueOptions) |
| 647 | } |
| 648 | |
| 649 | /** @inheritDoc */ |
| 650 | public setTasksQueueOptions (tasksQueueOptions: TasksQueueOptions): void { |
| 651 | if (this.opts.enableTasksQueue === true) { |
| 652 | this.checkValidTasksQueueOptions(tasksQueueOptions) |
| 653 | this.opts.tasksQueueOptions = |
| 654 | this.buildTasksQueueOptions(tasksQueueOptions) |
| 655 | this.setTasksQueueSize(this.opts.tasksQueueOptions.size as number) |
| 656 | } else if (this.opts.tasksQueueOptions != null) { |
| 657 | delete this.opts.tasksQueueOptions |
| 658 | } |
| 659 | } |
| 660 | |
| 661 | private setTasksQueueSize (size: number): void { |
| 662 | for (const workerNode of this.workerNodes) { |
| 663 | workerNode.tasksQueueBackPressureSize = size |
| 664 | } |
| 665 | } |
| 666 | |
| 667 | private buildTasksQueueOptions ( |
| 668 | tasksQueueOptions: TasksQueueOptions |
| 669 | ): TasksQueueOptions { |
| 670 | return { |
| 671 | ...{ |
| 672 | size: Math.pow(this.maxSize, 2), |
| 673 | concurrency: 1, |
| 674 | taskStealing: true, |
| 675 | tasksStealingOnBackPressure: true |
| 676 | }, |
| 677 | ...tasksQueueOptions |
| 678 | } |
| 679 | } |
| 680 | |
| 681 | /** |
| 682 | * Whether the pool is full or not. |
| 683 | * |
| 684 | * The pool filling boolean status. |
| 685 | */ |
| 686 | protected get full (): boolean { |
| 687 | return this.workerNodes.length >= this.maxSize |
| 688 | } |
| 689 | |
| 690 | /** |
| 691 | * Whether the pool is busy or not. |
| 692 | * |
| 693 | * The pool busyness boolean status. |
| 694 | */ |
| 695 | protected abstract get busy (): boolean |
| 696 | |
| 697 | /** |
| 698 | * Whether worker nodes are executing concurrently their tasks quota or not. |
| 699 | * |
| 700 | * @returns Worker nodes busyness boolean status. |
| 701 | */ |
| 702 | protected internalBusy (): boolean { |
| 703 | if (this.opts.enableTasksQueue === true) { |
| 704 | return ( |
| 705 | this.workerNodes.findIndex( |
| 706 | workerNode => |
| 707 | workerNode.info.ready && |
| 708 | workerNode.usage.tasks.executing < |
| 709 | (this.opts.tasksQueueOptions?.concurrency as number) |
| 710 | ) === -1 |
| 711 | ) |
| 712 | } |
| 713 | return ( |
| 714 | this.workerNodes.findIndex( |
| 715 | workerNode => |
| 716 | workerNode.info.ready && workerNode.usage.tasks.executing === 0 |
| 717 | ) === -1 |
| 718 | ) |
| 719 | } |
| 720 | |
| 721 | private async sendTaskFunctionOperationToWorker ( |
| 722 | workerNodeKey: number, |
| 723 | message: MessageValue<Data> |
| 724 | ): Promise<boolean> { |
| 725 | const workerId = this.getWorkerInfo(workerNodeKey).id as number |
| 726 | return await new Promise<boolean>((resolve, reject) => { |
| 727 | this.registerWorkerMessageListener(workerNodeKey, message => { |
| 728 | if ( |
| 729 | message.workerId === workerId && |
| 730 | message.taskFunctionOperationStatus === true |
| 731 | ) { |
| 732 | resolve(true) |
| 733 | } else if ( |
| 734 | message.workerId === workerId && |
| 735 | message.taskFunctionOperationStatus === false |
| 736 | ) { |
| 737 | reject( |
| 738 | new Error( |
| 739 | `Task function operation ${ |
| 740 | message.taskFunctionOperation as string |
| 741 | } failed on worker ${message.workerId}` |
| 742 | ) |
| 743 | ) |
| 744 | } |
| 745 | }) |
| 746 | this.sendToWorker(workerNodeKey, message) |
| 747 | }) |
| 748 | } |
| 749 | |
| 750 | private async sendTaskFunctionOperationToWorkers ( |
| 751 | message: Omit<MessageValue<Data>, 'workerId'> |
| 752 | ): Promise<boolean> { |
| 753 | return await new Promise<boolean>((resolve, reject) => { |
| 754 | const responsesReceived = new Array<MessageValue<Data | Response>>() |
| 755 | for (const [workerNodeKey] of this.workerNodes.entries()) { |
| 756 | this.registerWorkerMessageListener(workerNodeKey, message => { |
| 757 | if (message.taskFunctionOperationStatus != null) { |
| 758 | responsesReceived.push(message) |
| 759 | if ( |
| 760 | responsesReceived.length === this.workerNodes.length && |
| 761 | responsesReceived.every( |
| 762 | message => message.taskFunctionOperationStatus === true |
| 763 | ) |
| 764 | ) { |
| 765 | resolve(true) |
| 766 | } else if ( |
| 767 | responsesReceived.length === this.workerNodes.length && |
| 768 | responsesReceived.some( |
| 769 | message => message.taskFunctionOperationStatus === false |
| 770 | ) |
| 771 | ) { |
| 772 | reject( |
| 773 | new Error( |
| 774 | `Task function operation ${ |
| 775 | message.taskFunctionOperation as string |
| 776 | } failed on worker ${message.workerId as number}` |
| 777 | ) |
| 778 | ) |
| 779 | } |
| 780 | } |
| 781 | }) |
| 782 | this.sendToWorker(workerNodeKey, message) |
| 783 | } |
| 784 | }) |
| 785 | } |
| 786 | |
| 787 | /** @inheritDoc */ |
| 788 | public hasTaskFunction (name: string): boolean { |
| 789 | for (const workerNode of this.workerNodes) { |
| 790 | if ( |
| 791 | Array.isArray(workerNode.info.taskFunctionNames) && |
| 792 | workerNode.info.taskFunctionNames.includes(name) |
| 793 | ) { |
| 794 | return true |
| 795 | } |
| 796 | } |
| 797 | return false |
| 798 | } |
| 799 | |
| 800 | /** @inheritDoc */ |
| 801 | public async addTaskFunction ( |
| 802 | name: string, |
| 803 | taskFunction: TaskFunction<Data, Response> |
| 804 | ): Promise<boolean> { |
| 805 | this.taskFunctions.set(name, taskFunction) |
| 806 | return await this.sendTaskFunctionOperationToWorkers({ |
| 807 | taskFunctionOperation: 'add', |
| 808 | taskFunctionName: name, |
| 809 | taskFunction: taskFunction.toString() |
| 810 | }) |
| 811 | } |
| 812 | |
| 813 | /** @inheritDoc */ |
| 814 | public async removeTaskFunction (name: string): Promise<boolean> { |
| 815 | this.taskFunctions.delete(name) |
| 816 | return await this.sendTaskFunctionOperationToWorkers({ |
| 817 | taskFunctionOperation: 'remove', |
| 818 | taskFunctionName: name |
| 819 | }) |
| 820 | } |
| 821 | |
| 822 | /** @inheritDoc */ |
| 823 | public listTaskFunctionNames (): string[] { |
| 824 | for (const workerNode of this.workerNodes) { |
| 825 | if ( |
| 826 | Array.isArray(workerNode.info.taskFunctionNames) && |
| 827 | workerNode.info.taskFunctionNames.length > 0 |
| 828 | ) { |
| 829 | return workerNode.info.taskFunctionNames |
| 830 | } |
| 831 | } |
| 832 | return [] |
| 833 | } |
| 834 | |
| 835 | /** @inheritDoc */ |
| 836 | public async setDefaultTaskFunction (name: string): Promise<boolean> { |
| 837 | return await this.sendTaskFunctionOperationToWorkers({ |
| 838 | taskFunctionOperation: 'default', |
| 839 | taskFunctionName: name |
| 840 | }) |
| 841 | } |
| 842 | |
| 843 | private shallExecuteTask (workerNodeKey: number): boolean { |
| 844 | return ( |
| 845 | this.tasksQueueSize(workerNodeKey) === 0 && |
| 846 | this.workerNodes[workerNodeKey].usage.tasks.executing < |
| 847 | (this.opts.tasksQueueOptions?.concurrency as number) |
| 848 | ) |
| 849 | } |
| 850 | |
| 851 | /** @inheritDoc */ |
| 852 | public async execute ( |
| 853 | data?: Data, |
| 854 | name?: string, |
| 855 | transferList?: TransferListItem[] |
| 856 | ): Promise<Response> { |
| 857 | return await new Promise<Response>((resolve, reject) => { |
| 858 | if (!this.started) { |
| 859 | reject(new Error('Cannot execute a task on not started pool')) |
| 860 | return |
| 861 | } |
| 862 | if (name != null && typeof name !== 'string') { |
| 863 | reject(new TypeError('name argument must be a string')) |
| 864 | return |
| 865 | } |
| 866 | if ( |
| 867 | name != null && |
| 868 | typeof name === 'string' && |
| 869 | name.trim().length === 0 |
| 870 | ) { |
| 871 | reject(new TypeError('name argument must not be an empty string')) |
| 872 | return |
| 873 | } |
| 874 | if (transferList != null && !Array.isArray(transferList)) { |
| 875 | reject(new TypeError('transferList argument must be an array')) |
| 876 | return |
| 877 | } |
| 878 | const timestamp = performance.now() |
| 879 | const workerNodeKey = this.chooseWorkerNode() |
| 880 | const task: Task<Data> = { |
| 881 | name: name ?? DEFAULT_TASK_NAME, |
| 882 | // eslint-disable-next-line @typescript-eslint/consistent-type-assertions |
| 883 | data: data ?? ({} as Data), |
| 884 | transferList, |
| 885 | timestamp, |
| 886 | taskId: randomUUID() |
| 887 | } |
| 888 | this.promiseResponseMap.set(task.taskId as string, { |
| 889 | resolve, |
| 890 | reject, |
| 891 | workerNodeKey |
| 892 | }) |
| 893 | if ( |
| 894 | this.opts.enableTasksQueue === false || |
| 895 | (this.opts.enableTasksQueue === true && |
| 896 | this.shallExecuteTask(workerNodeKey)) |
| 897 | ) { |
| 898 | this.executeTask(workerNodeKey, task) |
| 899 | } else { |
| 900 | this.enqueueTask(workerNodeKey, task) |
| 901 | } |
| 902 | }) |
| 903 | } |
| 904 | |
| 905 | /** @inheritdoc */ |
| 906 | public start (): void { |
| 907 | this.starting = true |
| 908 | while ( |
| 909 | this.workerNodes.reduce( |
| 910 | (accumulator, workerNode) => |
| 911 | !workerNode.info.dynamic ? accumulator + 1 : accumulator, |
| 912 | 0 |
| 913 | ) < this.numberOfWorkers |
| 914 | ) { |
| 915 | this.createAndSetupWorkerNode() |
| 916 | } |
| 917 | this.starting = false |
| 918 | this.started = true |
| 919 | } |
| 920 | |
| 921 | /** @inheritDoc */ |
| 922 | public async destroy (): Promise<void> { |
| 923 | await Promise.all( |
| 924 | this.workerNodes.map(async (_, workerNodeKey) => { |
| 925 | await this.destroyWorkerNode(workerNodeKey) |
| 926 | }) |
| 927 | ) |
| 928 | this.emitter?.emit(PoolEvents.destroy, this.info) |
| 929 | this.started = false |
| 930 | } |
| 931 | |
| 932 | protected async sendKillMessageToWorker ( |
| 933 | workerNodeKey: number |
| 934 | ): Promise<void> { |
| 935 | await new Promise<void>((resolve, reject) => { |
| 936 | this.registerWorkerMessageListener(workerNodeKey, message => { |
| 937 | if (message.kill === 'success') { |
| 938 | resolve() |
| 939 | } else if (message.kill === 'failure') { |
| 940 | reject( |
| 941 | new Error( |
| 942 | `Worker ${ |
| 943 | message.workerId as number |
| 944 | } kill message handling failed` |
| 945 | ) |
| 946 | ) |
| 947 | } |
| 948 | }) |
| 949 | this.sendToWorker(workerNodeKey, { kill: true }) |
| 950 | }) |
| 951 | } |
| 952 | |
| 953 | /** |
| 954 | * Terminates the worker node given its worker node key. |
| 955 | * |
| 956 | * @param workerNodeKey - The worker node key. |
| 957 | */ |
| 958 | protected abstract destroyWorkerNode (workerNodeKey: number): Promise<void> |
| 959 | |
| 960 | /** |
| 961 | * Setup hook to execute code before worker nodes are created in the abstract constructor. |
| 962 | * Can be overridden. |
| 963 | * |
| 964 | * @virtual |
| 965 | */ |
| 966 | protected setupHook (): void { |
| 967 | /* Intentionally empty */ |
| 968 | } |
| 969 | |
| 970 | /** |
| 971 | * Should return whether the worker is the main worker or not. |
| 972 | */ |
| 973 | protected abstract isMain (): boolean |
| 974 | |
| 975 | /** |
| 976 | * Hook executed before the worker task execution. |
| 977 | * Can be overridden. |
| 978 | * |
| 979 | * @param workerNodeKey - The worker node key. |
| 980 | * @param task - The task to execute. |
| 981 | */ |
| 982 | protected beforeTaskExecutionHook ( |
| 983 | workerNodeKey: number, |
| 984 | task: Task<Data> |
| 985 | ): void { |
| 986 | if (this.workerNodes[workerNodeKey]?.usage != null) { |
| 987 | const workerUsage = this.workerNodes[workerNodeKey].usage |
| 988 | ++workerUsage.tasks.executing |
| 989 | this.updateWaitTimeWorkerUsage(workerUsage, task) |
| 990 | } |
| 991 | if ( |
| 992 | this.shallUpdateTaskFunctionWorkerUsage(workerNodeKey) && |
| 993 | this.workerNodes[workerNodeKey].getTaskFunctionWorkerUsage( |
| 994 | task.name as string |
| 995 | ) != null |
| 996 | ) { |
| 997 | const taskFunctionWorkerUsage = this.workerNodes[ |
| 998 | workerNodeKey |
| 999 | ].getTaskFunctionWorkerUsage(task.name as string) as WorkerUsage |
| 1000 | ++taskFunctionWorkerUsage.tasks.executing |
| 1001 | this.updateWaitTimeWorkerUsage(taskFunctionWorkerUsage, task) |
| 1002 | } |
| 1003 | } |
| 1004 | |
| 1005 | /** |
| 1006 | * Hook executed after the worker task execution. |
| 1007 | * Can be overridden. |
| 1008 | * |
| 1009 | * @param workerNodeKey - The worker node key. |
| 1010 | * @param message - The received message. |
| 1011 | */ |
| 1012 | protected afterTaskExecutionHook ( |
| 1013 | workerNodeKey: number, |
| 1014 | message: MessageValue<Response> |
| 1015 | ): void { |
| 1016 | if (this.workerNodes[workerNodeKey]?.usage != null) { |
| 1017 | const workerUsage = this.workerNodes[workerNodeKey].usage |
| 1018 | this.updateTaskStatisticsWorkerUsage(workerUsage, message) |
| 1019 | this.updateRunTimeWorkerUsage(workerUsage, message) |
| 1020 | this.updateEluWorkerUsage(workerUsage, message) |
| 1021 | } |
| 1022 | if ( |
| 1023 | this.shallUpdateTaskFunctionWorkerUsage(workerNodeKey) && |
| 1024 | this.workerNodes[workerNodeKey].getTaskFunctionWorkerUsage( |
| 1025 | message.taskPerformance?.name as string |
| 1026 | ) != null |
| 1027 | ) { |
| 1028 | const taskFunctionWorkerUsage = this.workerNodes[ |
| 1029 | workerNodeKey |
| 1030 | ].getTaskFunctionWorkerUsage( |
| 1031 | message.taskPerformance?.name as string |
| 1032 | ) as WorkerUsage |
| 1033 | this.updateTaskStatisticsWorkerUsage(taskFunctionWorkerUsage, message) |
| 1034 | this.updateRunTimeWorkerUsage(taskFunctionWorkerUsage, message) |
| 1035 | this.updateEluWorkerUsage(taskFunctionWorkerUsage, message) |
| 1036 | } |
| 1037 | } |
| 1038 | |
| 1039 | /** |
| 1040 | * Whether the worker node shall update its task function worker usage or not. |
| 1041 | * |
| 1042 | * @param workerNodeKey - The worker node key. |
| 1043 | * @returns `true` if the worker node shall update its task function worker usage, `false` otherwise. |
| 1044 | */ |
| 1045 | private shallUpdateTaskFunctionWorkerUsage (workerNodeKey: number): boolean { |
| 1046 | const workerInfo = this.getWorkerInfo(workerNodeKey) |
| 1047 | return ( |
| 1048 | workerInfo != null && |
| 1049 | Array.isArray(workerInfo.taskFunctionNames) && |
| 1050 | workerInfo.taskFunctionNames.length > 2 |
| 1051 | ) |
| 1052 | } |
| 1053 | |
| 1054 | private updateTaskStatisticsWorkerUsage ( |
| 1055 | workerUsage: WorkerUsage, |
| 1056 | message: MessageValue<Response> |
| 1057 | ): void { |
| 1058 | const workerTaskStatistics = workerUsage.tasks |
| 1059 | if ( |
| 1060 | workerTaskStatistics.executing != null && |
| 1061 | workerTaskStatistics.executing > 0 |
| 1062 | ) { |
| 1063 | --workerTaskStatistics.executing |
| 1064 | } |
| 1065 | if (message.workerError == null) { |
| 1066 | ++workerTaskStatistics.executed |
| 1067 | } else { |
| 1068 | ++workerTaskStatistics.failed |
| 1069 | } |
| 1070 | } |
| 1071 | |
| 1072 | private updateRunTimeWorkerUsage ( |
| 1073 | workerUsage: WorkerUsage, |
| 1074 | message: MessageValue<Response> |
| 1075 | ): void { |
| 1076 | if (message.workerError != null) { |
| 1077 | return |
| 1078 | } |
| 1079 | updateMeasurementStatistics( |
| 1080 | workerUsage.runTime, |
| 1081 | this.workerChoiceStrategyContext.getTaskStatisticsRequirements().runTime, |
| 1082 | message.taskPerformance?.runTime ?? 0 |
| 1083 | ) |
| 1084 | } |
| 1085 | |
| 1086 | private updateWaitTimeWorkerUsage ( |
| 1087 | workerUsage: WorkerUsage, |
| 1088 | task: Task<Data> |
| 1089 | ): void { |
| 1090 | const timestamp = performance.now() |
| 1091 | const taskWaitTime = timestamp - (task.timestamp ?? timestamp) |
| 1092 | updateMeasurementStatistics( |
| 1093 | workerUsage.waitTime, |
| 1094 | this.workerChoiceStrategyContext.getTaskStatisticsRequirements().waitTime, |
| 1095 | taskWaitTime |
| 1096 | ) |
| 1097 | } |
| 1098 | |
| 1099 | private updateEluWorkerUsage ( |
| 1100 | workerUsage: WorkerUsage, |
| 1101 | message: MessageValue<Response> |
| 1102 | ): void { |
| 1103 | if (message.workerError != null) { |
| 1104 | return |
| 1105 | } |
| 1106 | const eluTaskStatisticsRequirements: MeasurementStatisticsRequirements = |
| 1107 | this.workerChoiceStrategyContext.getTaskStatisticsRequirements().elu |
| 1108 | updateMeasurementStatistics( |
| 1109 | workerUsage.elu.active, |
| 1110 | eluTaskStatisticsRequirements, |
| 1111 | message.taskPerformance?.elu?.active ?? 0 |
| 1112 | ) |
| 1113 | updateMeasurementStatistics( |
| 1114 | workerUsage.elu.idle, |
| 1115 | eluTaskStatisticsRequirements, |
| 1116 | message.taskPerformance?.elu?.idle ?? 0 |
| 1117 | ) |
| 1118 | if (eluTaskStatisticsRequirements.aggregate) { |
| 1119 | if (message.taskPerformance?.elu != null) { |
| 1120 | if (workerUsage.elu.utilization != null) { |
| 1121 | workerUsage.elu.utilization = |
| 1122 | (workerUsage.elu.utilization + |
| 1123 | message.taskPerformance.elu.utilization) / |
| 1124 | 2 |
| 1125 | } else { |
| 1126 | workerUsage.elu.utilization = message.taskPerformance.elu.utilization |
| 1127 | } |
| 1128 | } |
| 1129 | } |
| 1130 | } |
| 1131 | |
| 1132 | /** |
| 1133 | * Chooses a worker node for the next task. |
| 1134 | * |
| 1135 | * The default worker choice strategy uses a round robin algorithm to distribute the tasks. |
| 1136 | * |
| 1137 | * @returns The chosen worker node key |
| 1138 | */ |
| 1139 | private chooseWorkerNode (): number { |
| 1140 | if (this.shallCreateDynamicWorker()) { |
| 1141 | const workerNodeKey = this.createAndSetupDynamicWorkerNode() |
| 1142 | if ( |
| 1143 | this.workerChoiceStrategyContext.getStrategyPolicy().dynamicWorkerUsage |
| 1144 | ) { |
| 1145 | return workerNodeKey |
| 1146 | } |
| 1147 | } |
| 1148 | return this.workerChoiceStrategyContext.execute() |
| 1149 | } |
| 1150 | |
| 1151 | /** |
| 1152 | * Conditions for dynamic worker creation. |
| 1153 | * |
| 1154 | * @returns Whether to create a dynamic worker or not. |
| 1155 | */ |
| 1156 | private shallCreateDynamicWorker (): boolean { |
| 1157 | return this.type === PoolTypes.dynamic && !this.full && this.internalBusy() |
| 1158 | } |
| 1159 | |
| 1160 | /** |
| 1161 | * Sends a message to worker given its worker node key. |
| 1162 | * |
| 1163 | * @param workerNodeKey - The worker node key. |
| 1164 | * @param message - The message. |
| 1165 | * @param transferList - The optional array of transferable objects. |
| 1166 | */ |
| 1167 | protected abstract sendToWorker ( |
| 1168 | workerNodeKey: number, |
| 1169 | message: MessageValue<Data>, |
| 1170 | transferList?: TransferListItem[] |
| 1171 | ): void |
| 1172 | |
| 1173 | /** |
| 1174 | * Creates a new worker. |
| 1175 | * |
| 1176 | * @returns Newly created worker. |
| 1177 | */ |
| 1178 | protected abstract createWorker (): Worker |
| 1179 | |
| 1180 | /** |
| 1181 | * Creates a new, completely set up worker node. |
| 1182 | * |
| 1183 | * @returns New, completely set up worker node key. |
| 1184 | */ |
| 1185 | protected createAndSetupWorkerNode (): number { |
| 1186 | const worker = this.createWorker() |
| 1187 | |
| 1188 | worker.on('online', this.opts.onlineHandler ?? EMPTY_FUNCTION) |
| 1189 | worker.on('message', this.opts.messageHandler ?? EMPTY_FUNCTION) |
| 1190 | worker.on('error', this.opts.errorHandler ?? EMPTY_FUNCTION) |
| 1191 | worker.on('error', error => { |
| 1192 | const workerNodeKey = this.getWorkerNodeKeyByWorker(worker) |
| 1193 | const workerInfo = this.getWorkerInfo(workerNodeKey) |
| 1194 | workerInfo.ready = false |
| 1195 | this.workerNodes[workerNodeKey].closeChannel() |
| 1196 | this.emitter?.emit(PoolEvents.error, error) |
| 1197 | if ( |
| 1198 | this.opts.restartWorkerOnError === true && |
| 1199 | this.started && |
| 1200 | !this.starting |
| 1201 | ) { |
| 1202 | if (workerInfo.dynamic) { |
| 1203 | this.createAndSetupDynamicWorkerNode() |
| 1204 | } else { |
| 1205 | this.createAndSetupWorkerNode() |
| 1206 | } |
| 1207 | } |
| 1208 | if (this.opts.enableTasksQueue === true) { |
| 1209 | this.redistributeQueuedTasks(workerNodeKey) |
| 1210 | } |
| 1211 | }) |
| 1212 | worker.on('exit', this.opts.exitHandler ?? EMPTY_FUNCTION) |
| 1213 | worker.once('exit', () => { |
| 1214 | this.removeWorkerNode(worker) |
| 1215 | }) |
| 1216 | |
| 1217 | const workerNodeKey = this.addWorkerNode(worker) |
| 1218 | |
| 1219 | this.afterWorkerNodeSetup(workerNodeKey) |
| 1220 | |
| 1221 | return workerNodeKey |
| 1222 | } |
| 1223 | |
| 1224 | /** |
| 1225 | * Creates a new, completely set up dynamic worker node. |
| 1226 | * |
| 1227 | * @returns New, completely set up dynamic worker node key. |
| 1228 | */ |
| 1229 | protected createAndSetupDynamicWorkerNode (): number { |
| 1230 | const workerNodeKey = this.createAndSetupWorkerNode() |
| 1231 | this.registerWorkerMessageListener(workerNodeKey, message => { |
| 1232 | const localWorkerNodeKey = this.getWorkerNodeKeyByWorkerId( |
| 1233 | message.workerId |
| 1234 | ) |
| 1235 | const workerUsage = this.workerNodes[localWorkerNodeKey].usage |
| 1236 | // Kill message received from worker |
| 1237 | if ( |
| 1238 | isKillBehavior(KillBehaviors.HARD, message.kill) || |
| 1239 | (isKillBehavior(KillBehaviors.SOFT, message.kill) && |
| 1240 | ((this.opts.enableTasksQueue === false && |
| 1241 | workerUsage.tasks.executing === 0) || |
| 1242 | (this.opts.enableTasksQueue === true && |
| 1243 | workerUsage.tasks.executing === 0 && |
| 1244 | this.tasksQueueSize(localWorkerNodeKey) === 0))) |
| 1245 | ) { |
| 1246 | this.destroyWorkerNode(localWorkerNodeKey).catch(error => { |
| 1247 | this.emitter?.emit(PoolEvents.error, error) |
| 1248 | }) |
| 1249 | } |
| 1250 | }) |
| 1251 | const workerInfo = this.getWorkerInfo(workerNodeKey) |
| 1252 | this.sendToWorker(workerNodeKey, { |
| 1253 | checkActive: true |
| 1254 | }) |
| 1255 | if (this.taskFunctions.size > 0) { |
| 1256 | for (const [taskFunctionName, taskFunction] of this.taskFunctions) { |
| 1257 | this.sendTaskFunctionOperationToWorker(workerNodeKey, { |
| 1258 | taskFunctionOperation: 'add', |
| 1259 | taskFunctionName, |
| 1260 | taskFunction: taskFunction.toString() |
| 1261 | }).catch(error => { |
| 1262 | this.emitter?.emit(PoolEvents.error, error) |
| 1263 | }) |
| 1264 | } |
| 1265 | } |
| 1266 | workerInfo.dynamic = true |
| 1267 | if ( |
| 1268 | this.workerChoiceStrategyContext.getStrategyPolicy().dynamicWorkerReady || |
| 1269 | this.workerChoiceStrategyContext.getStrategyPolicy().dynamicWorkerUsage |
| 1270 | ) { |
| 1271 | workerInfo.ready = true |
| 1272 | } |
| 1273 | this.checkAndEmitDynamicWorkerCreationEvents() |
| 1274 | return workerNodeKey |
| 1275 | } |
| 1276 | |
| 1277 | /** |
| 1278 | * Registers a listener callback on the worker given its worker node key. |
| 1279 | * |
| 1280 | * @param workerNodeKey - The worker node key. |
| 1281 | * @param listener - The message listener callback. |
| 1282 | */ |
| 1283 | protected abstract registerWorkerMessageListener< |
| 1284 | Message extends Data | Response |
| 1285 | >( |
| 1286 | workerNodeKey: number, |
| 1287 | listener: (message: MessageValue<Message>) => void |
| 1288 | ): void |
| 1289 | |
| 1290 | /** |
| 1291 | * Method hooked up after a worker node has been newly created. |
| 1292 | * Can be overridden. |
| 1293 | * |
| 1294 | * @param workerNodeKey - The newly created worker node key. |
| 1295 | */ |
| 1296 | protected afterWorkerNodeSetup (workerNodeKey: number): void { |
| 1297 | // Listen to worker messages. |
| 1298 | this.registerWorkerMessageListener(workerNodeKey, this.workerListener()) |
| 1299 | // Send the startup message to worker. |
| 1300 | this.sendStartupMessageToWorker(workerNodeKey) |
| 1301 | // Send the statistics message to worker. |
| 1302 | this.sendStatisticsMessageToWorker(workerNodeKey) |
| 1303 | if (this.opts.enableTasksQueue === true) { |
| 1304 | if (this.opts.tasksQueueOptions?.taskStealing === true) { |
| 1305 | this.workerNodes[workerNodeKey].onEmptyQueue = |
| 1306 | this.taskStealingOnEmptyQueue.bind(this) |
| 1307 | } |
| 1308 | if (this.opts.tasksQueueOptions?.tasksStealingOnBackPressure === true) { |
| 1309 | this.workerNodes[workerNodeKey].onBackPressure = |
| 1310 | this.tasksStealingOnBackPressure.bind(this) |
| 1311 | } |
| 1312 | } |
| 1313 | } |
| 1314 | |
| 1315 | /** |
| 1316 | * Sends the startup message to worker given its worker node key. |
| 1317 | * |
| 1318 | * @param workerNodeKey - The worker node key. |
| 1319 | */ |
| 1320 | protected abstract sendStartupMessageToWorker (workerNodeKey: number): void |
| 1321 | |
| 1322 | /** |
| 1323 | * Sends the statistics message to worker given its worker node key. |
| 1324 | * |
| 1325 | * @param workerNodeKey - The worker node key. |
| 1326 | */ |
| 1327 | private sendStatisticsMessageToWorker (workerNodeKey: number): void { |
| 1328 | this.sendToWorker(workerNodeKey, { |
| 1329 | statistics: { |
| 1330 | runTime: |
| 1331 | this.workerChoiceStrategyContext.getTaskStatisticsRequirements() |
| 1332 | .runTime.aggregate, |
| 1333 | elu: this.workerChoiceStrategyContext.getTaskStatisticsRequirements() |
| 1334 | .elu.aggregate |
| 1335 | } |
| 1336 | }) |
| 1337 | } |
| 1338 | |
| 1339 | private redistributeQueuedTasks (workerNodeKey: number): void { |
| 1340 | while (this.tasksQueueSize(workerNodeKey) > 0) { |
| 1341 | const destinationWorkerNodeKey = this.workerNodes.reduce( |
| 1342 | (minWorkerNodeKey, workerNode, workerNodeKey, workerNodes) => { |
| 1343 | return workerNode.info.ready && |
| 1344 | workerNode.usage.tasks.queued < |
| 1345 | workerNodes[minWorkerNodeKey].usage.tasks.queued |
| 1346 | ? workerNodeKey |
| 1347 | : minWorkerNodeKey |
| 1348 | }, |
| 1349 | 0 |
| 1350 | ) |
| 1351 | const task = this.dequeueTask(workerNodeKey) as Task<Data> |
| 1352 | if (this.shallExecuteTask(destinationWorkerNodeKey)) { |
| 1353 | this.executeTask(destinationWorkerNodeKey, task) |
| 1354 | } else { |
| 1355 | this.enqueueTask(destinationWorkerNodeKey, task) |
| 1356 | } |
| 1357 | } |
| 1358 | } |
| 1359 | |
| 1360 | private updateTaskStolenStatisticsWorkerUsage ( |
| 1361 | workerNodeKey: number, |
| 1362 | taskName: string |
| 1363 | ): void { |
| 1364 | const workerNode = this.workerNodes[workerNodeKey] |
| 1365 | if (workerNode?.usage != null) { |
| 1366 | ++workerNode.usage.tasks.stolen |
| 1367 | } |
| 1368 | if ( |
| 1369 | this.shallUpdateTaskFunctionWorkerUsage(workerNodeKey) && |
| 1370 | workerNode.getTaskFunctionWorkerUsage(taskName) != null |
| 1371 | ) { |
| 1372 | const taskFunctionWorkerUsage = workerNode.getTaskFunctionWorkerUsage( |
| 1373 | taskName |
| 1374 | ) as WorkerUsage |
| 1375 | ++taskFunctionWorkerUsage.tasks.stolen |
| 1376 | } |
| 1377 | } |
| 1378 | |
| 1379 | private taskStealingOnEmptyQueue (workerId: number): void { |
| 1380 | const destinationWorkerNodeKey = this.getWorkerNodeKeyByWorkerId(workerId) |
| 1381 | const workerNodes = this.workerNodes |
| 1382 | .slice() |
| 1383 | .sort( |
| 1384 | (workerNodeA, workerNodeB) => |
| 1385 | workerNodeB.usage.tasks.queued - workerNodeA.usage.tasks.queued |
| 1386 | ) |
| 1387 | const sourceWorkerNode = workerNodes.find( |
| 1388 | workerNode => |
| 1389 | workerNode.info.ready && |
| 1390 | workerNode.info.id !== workerId && |
| 1391 | workerNode.usage.tasks.queued > 0 |
| 1392 | ) |
| 1393 | if (sourceWorkerNode != null) { |
| 1394 | const task = sourceWorkerNode.popTask() as Task<Data> |
| 1395 | if (this.shallExecuteTask(destinationWorkerNodeKey)) { |
| 1396 | this.executeTask(destinationWorkerNodeKey, task) |
| 1397 | } else { |
| 1398 | this.enqueueTask(destinationWorkerNodeKey, task) |
| 1399 | } |
| 1400 | this.updateTaskStolenStatisticsWorkerUsage( |
| 1401 | destinationWorkerNodeKey, |
| 1402 | task.name as string |
| 1403 | ) |
| 1404 | } |
| 1405 | } |
| 1406 | |
| 1407 | private tasksStealingOnBackPressure (workerId: number): void { |
| 1408 | const sizeOffset = 1 |
| 1409 | if ((this.opts.tasksQueueOptions?.size as number) <= sizeOffset) { |
| 1410 | return |
| 1411 | } |
| 1412 | const sourceWorkerNode = |
| 1413 | this.workerNodes[this.getWorkerNodeKeyByWorkerId(workerId)] |
| 1414 | const workerNodes = this.workerNodes |
| 1415 | .slice() |
| 1416 | .sort( |
| 1417 | (workerNodeA, workerNodeB) => |
| 1418 | workerNodeA.usage.tasks.queued - workerNodeB.usage.tasks.queued |
| 1419 | ) |
| 1420 | for (const [workerNodeKey, workerNode] of workerNodes.entries()) { |
| 1421 | if ( |
| 1422 | sourceWorkerNode.usage.tasks.queued > 0 && |
| 1423 | workerNode.info.ready && |
| 1424 | workerNode.info.id !== workerId && |
| 1425 | workerNode.usage.tasks.queued < |
| 1426 | (this.opts.tasksQueueOptions?.size as number) - sizeOffset |
| 1427 | ) { |
| 1428 | const task = sourceWorkerNode.popTask() as Task<Data> |
| 1429 | if (this.shallExecuteTask(workerNodeKey)) { |
| 1430 | this.executeTask(workerNodeKey, task) |
| 1431 | } else { |
| 1432 | this.enqueueTask(workerNodeKey, task) |
| 1433 | } |
| 1434 | this.updateTaskStolenStatisticsWorkerUsage( |
| 1435 | workerNodeKey, |
| 1436 | task.name as string |
| 1437 | ) |
| 1438 | } |
| 1439 | } |
| 1440 | } |
| 1441 | |
| 1442 | /** |
| 1443 | * This method is the listener registered for each worker message. |
| 1444 | * |
| 1445 | * @returns The listener function to execute when a message is received from a worker. |
| 1446 | */ |
| 1447 | protected workerListener (): (message: MessageValue<Response>) => void { |
| 1448 | return message => { |
| 1449 | this.checkMessageWorkerId(message) |
| 1450 | if (message.ready != null && message.taskFunctionNames != null) { |
| 1451 | // Worker ready response received from worker |
| 1452 | this.handleWorkerReadyResponse(message) |
| 1453 | } else if (message.taskId != null) { |
| 1454 | // Task execution response received from worker |
| 1455 | this.handleTaskExecutionResponse(message) |
| 1456 | } else if (message.taskFunctionNames != null) { |
| 1457 | // Task function names message received from worker |
| 1458 | this.getWorkerInfo( |
| 1459 | this.getWorkerNodeKeyByWorkerId(message.workerId) |
| 1460 | ).taskFunctionNames = message.taskFunctionNames |
| 1461 | } |
| 1462 | } |
| 1463 | } |
| 1464 | |
| 1465 | private handleWorkerReadyResponse (message: MessageValue<Response>): void { |
| 1466 | if (message.ready === false) { |
| 1467 | throw new Error( |
| 1468 | `Worker ${message.workerId as number} failed to initialize` |
| 1469 | ) |
| 1470 | } |
| 1471 | const workerInfo = this.getWorkerInfo( |
| 1472 | this.getWorkerNodeKeyByWorkerId(message.workerId) |
| 1473 | ) |
| 1474 | workerInfo.ready = message.ready as boolean |
| 1475 | workerInfo.taskFunctionNames = message.taskFunctionNames |
| 1476 | if (this.emitter != null && this.ready) { |
| 1477 | this.emitter.emit(PoolEvents.ready, this.info) |
| 1478 | } |
| 1479 | } |
| 1480 | |
| 1481 | private handleTaskExecutionResponse (message: MessageValue<Response>): void { |
| 1482 | const { taskId, workerError, data } = message |
| 1483 | const promiseResponse = this.promiseResponseMap.get(taskId as string) |
| 1484 | if (promiseResponse != null) { |
| 1485 | if (workerError != null) { |
| 1486 | this.emitter?.emit(PoolEvents.taskError, workerError) |
| 1487 | promiseResponse.reject(workerError.message) |
| 1488 | } else { |
| 1489 | promiseResponse.resolve(data as Response) |
| 1490 | } |
| 1491 | const workerNodeKey = promiseResponse.workerNodeKey |
| 1492 | this.afterTaskExecutionHook(workerNodeKey, message) |
| 1493 | this.workerChoiceStrategyContext.update(workerNodeKey) |
| 1494 | this.promiseResponseMap.delete(taskId as string) |
| 1495 | if ( |
| 1496 | this.opts.enableTasksQueue === true && |
| 1497 | this.tasksQueueSize(workerNodeKey) > 0 && |
| 1498 | this.workerNodes[workerNodeKey].usage.tasks.executing < |
| 1499 | (this.opts.tasksQueueOptions?.concurrency as number) |
| 1500 | ) { |
| 1501 | this.executeTask( |
| 1502 | workerNodeKey, |
| 1503 | this.dequeueTask(workerNodeKey) as Task<Data> |
| 1504 | ) |
| 1505 | } |
| 1506 | } |
| 1507 | } |
| 1508 | |
| 1509 | private checkAndEmitTaskExecutionEvents (): void { |
| 1510 | if (this.busy) { |
| 1511 | this.emitter?.emit(PoolEvents.busy, this.info) |
| 1512 | } |
| 1513 | } |
| 1514 | |
| 1515 | private checkAndEmitTaskQueuingEvents (): void { |
| 1516 | if (this.hasBackPressure()) { |
| 1517 | this.emitter?.emit(PoolEvents.backPressure, this.info) |
| 1518 | } |
| 1519 | } |
| 1520 | |
| 1521 | private checkAndEmitDynamicWorkerCreationEvents (): void { |
| 1522 | if (this.type === PoolTypes.dynamic) { |
| 1523 | if (this.full) { |
| 1524 | this.emitter?.emit(PoolEvents.full, this.info) |
| 1525 | } |
| 1526 | } |
| 1527 | } |
| 1528 | |
| 1529 | /** |
| 1530 | * Gets the worker information given its worker node key. |
| 1531 | * |
| 1532 | * @param workerNodeKey - The worker node key. |
| 1533 | * @returns The worker information. |
| 1534 | */ |
| 1535 | protected getWorkerInfo (workerNodeKey: number): WorkerInfo { |
| 1536 | return this.workerNodes[workerNodeKey].info |
| 1537 | } |
| 1538 | |
| 1539 | /** |
| 1540 | * Adds the given worker in the pool worker nodes. |
| 1541 | * |
| 1542 | * @param worker - The worker. |
| 1543 | * @returns The added worker node key. |
| 1544 | * @throws {@link https://nodejs.org/api/errors.html#class-error} If the added worker node is not found. |
| 1545 | */ |
| 1546 | private addWorkerNode (worker: Worker): number { |
| 1547 | const workerNode = new WorkerNode<Worker, Data>( |
| 1548 | worker, |
| 1549 | this.opts.tasksQueueOptions?.size ?? Math.pow(this.maxSize, 2) |
| 1550 | ) |
| 1551 | // Flag the worker node as ready at pool startup. |
| 1552 | if (this.starting) { |
| 1553 | workerNode.info.ready = true |
| 1554 | } |
| 1555 | this.workerNodes.push(workerNode) |
| 1556 | const workerNodeKey = this.getWorkerNodeKeyByWorker(worker) |
| 1557 | if (workerNodeKey === -1) { |
| 1558 | throw new Error('Worker added not found in worker nodes') |
| 1559 | } |
| 1560 | return workerNodeKey |
| 1561 | } |
| 1562 | |
| 1563 | /** |
| 1564 | * Removes the given worker from the pool worker nodes. |
| 1565 | * |
| 1566 | * @param worker - The worker. |
| 1567 | */ |
| 1568 | private removeWorkerNode (worker: Worker): void { |
| 1569 | const workerNodeKey = this.getWorkerNodeKeyByWorker(worker) |
| 1570 | if (workerNodeKey !== -1) { |
| 1571 | this.workerNodes.splice(workerNodeKey, 1) |
| 1572 | this.workerChoiceStrategyContext.remove(workerNodeKey) |
| 1573 | } |
| 1574 | } |
| 1575 | |
| 1576 | /** @inheritDoc */ |
| 1577 | public hasWorkerNodeBackPressure (workerNodeKey: number): boolean { |
| 1578 | return ( |
| 1579 | this.opts.enableTasksQueue === true && |
| 1580 | this.workerNodes[workerNodeKey].hasBackPressure() |
| 1581 | ) |
| 1582 | } |
| 1583 | |
| 1584 | private hasBackPressure (): boolean { |
| 1585 | return ( |
| 1586 | this.opts.enableTasksQueue === true && |
| 1587 | this.workerNodes.findIndex( |
| 1588 | workerNode => !workerNode.hasBackPressure() |
| 1589 | ) === -1 |
| 1590 | ) |
| 1591 | } |
| 1592 | |
| 1593 | /** |
| 1594 | * Executes the given task on the worker given its worker node key. |
| 1595 | * |
| 1596 | * @param workerNodeKey - The worker node key. |
| 1597 | * @param task - The task to execute. |
| 1598 | */ |
| 1599 | private executeTask (workerNodeKey: number, task: Task<Data>): void { |
| 1600 | this.beforeTaskExecutionHook(workerNodeKey, task) |
| 1601 | this.sendToWorker(workerNodeKey, task, task.transferList) |
| 1602 | this.checkAndEmitTaskExecutionEvents() |
| 1603 | } |
| 1604 | |
| 1605 | private enqueueTask (workerNodeKey: number, task: Task<Data>): number { |
| 1606 | const tasksQueueSize = this.workerNodes[workerNodeKey].enqueueTask(task) |
| 1607 | this.checkAndEmitTaskQueuingEvents() |
| 1608 | return tasksQueueSize |
| 1609 | } |
| 1610 | |
| 1611 | private dequeueTask (workerNodeKey: number): Task<Data> | undefined { |
| 1612 | return this.workerNodes[workerNodeKey].dequeueTask() |
| 1613 | } |
| 1614 | |
| 1615 | private tasksQueueSize (workerNodeKey: number): number { |
| 1616 | return this.workerNodes[workerNodeKey].tasksQueueSize() |
| 1617 | } |
| 1618 | |
| 1619 | protected flushTasksQueue (workerNodeKey: number): void { |
| 1620 | while (this.tasksQueueSize(workerNodeKey) > 0) { |
| 1621 | this.executeTask( |
| 1622 | workerNodeKey, |
| 1623 | this.dequeueTask(workerNodeKey) as Task<Data> |
| 1624 | ) |
| 1625 | } |
| 1626 | this.workerNodes[workerNodeKey].clearTasksQueue() |
| 1627 | } |
| 1628 | |
| 1629 | private flushTasksQueues (): void { |
| 1630 | for (const [workerNodeKey] of this.workerNodes.entries()) { |
| 1631 | this.flushTasksQueue(workerNodeKey) |
| 1632 | } |
| 1633 | } |
| 1634 | } |