+
+ /** @inheritDoc */
+ public setOptions (opts: WorkerChoiceStrategyOptions): void {
+ opts = opts ?? DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
+ this.setTaskStatistics(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 `avgRunTime`, the average runtime is returned.
+ * If the task statistics require `medRunTime`, the median runtime is returned.
+ *
+ * @param workerNodeKey - The worker node key.
+ * @returns The worker task runtime.
+ */
+ protected getWorkerTaskRunTime (workerNodeKey: number): number {
+ return this.taskStatisticsRequirements.medRunTime
+ ? 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 `avgWaitTime`, the average wait time is returned.
+ * If the task statistics require `medWaitTime`, the median wait time is returned.
+ *
+ * @param workerNodeKey - The worker node key.
+ * @returns The worker task wait time.
+ */
+ protected getWorkerWaitTime (workerNodeKey: number): number {
+ return this.taskStatisticsRequirements.medWaitTime
+ ? this.pool.workerNodes[workerNodeKey].workerUsage.runTime.median
+ : this.pool.workerNodes[workerNodeKey].workerUsage.runTime.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` running 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
+ })
+ }
+
+ /**
+ * Finds the last free worker node key based on the number of tasks the worker has applied.
+ *
+ * If a worker is found with `0` running 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 findLastFreeWorkerNodeKey (): number {
+ // It requires node >= 18.0.0:
+ // return this.workerNodes.findLastIndex(workerNode => {
+ // return workerNode.workerUsage.tasks.executing === 0
+ // })
+ for (
+ let workerNodeKey = this.pool.workerNodes.length - 1;
+ workerNodeKey >= 0;
+ workerNodeKey--
+ ) {
+ if (
+ this.pool.workerNodes[workerNodeKey].workerUsage.tasks.executing === 0
+ ) {
+ return workerNodeKey
+ }
+ }
+ return -1
+ }