+ protected readonly pool: IPool<Worker, Data, Response>,
+ protected opts: WorkerChoiceStrategyOptions = DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
+ ) {
+ this.choose = this.choose.bind(this)
+ }
+
+ protected setTaskStatisticsRequirements (
+ opts: WorkerChoiceStrategyOptions
+ ): void {
+ if (
+ this.taskStatisticsRequirements.runTime.average &&
+ opts.runTime?.median === true
+ ) {
+ this.taskStatisticsRequirements.runTime.average = false
+ this.taskStatisticsRequirements.runTime.median = opts.runTime
+ .median as boolean
+ }
+ if (
+ this.taskStatisticsRequirements.runTime.median &&
+ opts.runTime?.median === false
+ ) {
+ this.taskStatisticsRequirements.runTime.average = true
+ this.taskStatisticsRequirements.runTime.median = opts.runTime
+ .median as boolean
+ }
+ if (
+ this.taskStatisticsRequirements.waitTime.average &&
+ opts.waitTime?.median === true
+ ) {
+ this.taskStatisticsRequirements.waitTime.average = false
+ this.taskStatisticsRequirements.waitTime.median = opts.waitTime
+ .median as boolean
+ }
+ if (
+ this.taskStatisticsRequirements.waitTime.median &&
+ opts.waitTime?.median === false
+ ) {
+ this.taskStatisticsRequirements.waitTime.average = true
+ this.taskStatisticsRequirements.waitTime.median = opts.waitTime
+ .median as boolean
+ }
+ if (
+ this.taskStatisticsRequirements.elu.average &&
+ opts.elu?.median === true
+ ) {
+ this.taskStatisticsRequirements.elu.average = false
+ this.taskStatisticsRequirements.elu.median = opts.elu.median as boolean
+ }
+ if (
+ this.taskStatisticsRequirements.elu.median &&
+ opts.elu?.median === false
+ ) {
+ this.taskStatisticsRequirements.elu.average = true
+ this.taskStatisticsRequirements.elu.median = opts.elu.median as boolean
+ }
+ }
+
+ /** @inheritDoc */
+ public abstract reset (): boolean
+
+ /** @inheritDoc */
+ public abstract update (workerNodeKey: number): boolean
+
+ /** @inheritDoc */
+ public abstract choose (): number
+
+ /** @inheritDoc */
+ public abstract remove (workerNodeKey: number): boolean
+
+ /** @inheritDoc */
+ public setOptions (opts: WorkerChoiceStrategyOptions): void {
+ opts = opts ?? DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
+ this.setTaskStatisticsRequirements(opts)
+ this.opts = opts
+ }
+
+ /**
+ * Finds a free worker node key.
+ *
+ * @returns The free worker node key or `-1` if there is no free worker node.
+ */
+ protected findFreeWorkerNodeKey (): number {
+ if (this.toggleFindLastFreeWorkerNodeKey) {
+ this.toggleFindLastFreeWorkerNodeKey = false
+ return this.findLastFreeWorkerNodeKey()
+ }
+ this.toggleFindLastFreeWorkerNodeKey = true
+ return this.findFirstFreeWorkerNodeKey()
+ }
+
+ /**
+ * Gets the worker task runtime.
+ * If the task statistics require the average runtime, the average runtime is returned.
+ * If the task statistics require the median runtime , the median runtime is returned.
+ *
+ * @param workerNodeKey - The worker node key.
+ * @returns The worker task runtime.
+ */
+ protected getWorkerTaskRunTime (workerNodeKey: number): number {
+ return this.taskStatisticsRequirements.runTime.median
+ ? this.pool.workerNodes[workerNodeKey].workerUsage.runTime.median
+ : this.pool.workerNodes[workerNodeKey].workerUsage.runTime.average
+ }
+
+ /**
+ * Gets the worker task wait time.
+ * If the task statistics require the average wait time, the average wait time is returned.
+ * If the task statistics require the median wait time, the median wait time is returned.
+ *
+ * @param workerNodeKey - The worker node key.
+ * @returns The worker task wait time.
+ */
+ protected getWorkerTaskWaitTime (workerNodeKey: number): number {
+ return this.taskStatisticsRequirements.waitTime.median
+ ? this.pool.workerNodes[workerNodeKey].workerUsage.runTime.median
+ : this.pool.workerNodes[workerNodeKey].workerUsage.runTime.average
+ }
+
+ /**
+ * Gets the worker task ELU.
+ * If the task statistics require the average ELU, the average ELU is returned.
+ * If the task statistics require the median ELU, the median ELU is returned.
+ *
+ * @param workerNodeKey - The worker node key.
+ * @returns The worker task ELU.
+ */
+ protected getWorkerTaskElu (workerNodeKey: number): number {
+ return this.taskStatisticsRequirements.elu.median
+ ? this.pool.workerNodes[workerNodeKey].workerUsage.elu.active.median
+ : this.pool.workerNodes[workerNodeKey].workerUsage.elu.active.average
+ }
+
+ protected computeDefaultWorkerWeight (): number {
+ let cpusCycleTimeWeight = 0
+ for (const cpu of cpus()) {
+ // CPU estimated cycle time
+ const numberOfDigits = cpu.speed.toString().length - 1
+ const cpuCycleTime = 1 / (cpu.speed / Math.pow(10, numberOfDigits))
+ cpusCycleTimeWeight += cpuCycleTime * Math.pow(10, numberOfDigits)
+ }
+ return Math.round(cpusCycleTimeWeight / cpus().length)
+ }
+
+ /**
+ * Finds the first free worker node key based on the number of tasks the worker has applied.
+ *
+ * If a worker is found with `0` executing tasks, it is detected as free and its worker node key is returned.
+ *
+ * If no free worker is found, `-1` is returned.
+ *
+ * @returns A worker node key if there is one, `-1` otherwise.
+ */
+ private findFirstFreeWorkerNodeKey (): number {
+ return this.pool.workerNodes.findIndex(workerNode => {
+ return workerNode.workerUsage.tasks.executing === 0
+ })
+ }