*/
ROUND_ROBIN: 'ROUND_ROBIN',
/**
- * Less used worker selection strategy.
+ * Least used worker selection strategy.
*/
- LESS_USED: 'LESS_USED',
+ LEAST_USED: 'LEAST_USED',
/**
- * Less busy worker selection strategy.
+ * Least busy worker selection strategy.
*/
- LESS_BUSY: 'LESS_BUSY',
+ LEAST_BUSY: 'LEAST_BUSY',
+ /**
+ * Least ELU worker selection strategy.
+ */
+ LEAST_ELU: 'LEAST_ELU',
/**
* Fair share worker selection strategy.
*/
*/
export type WorkerChoiceStrategy = keyof typeof WorkerChoiceStrategies
+/**
+ * Enumeration of measurements.
+ */
+export const Measurements = Object.freeze({
+ runTime: 'runTime',
+ waitTime: 'waitTime',
+ elu: 'elu'
+} as const)
+
+/**
+ * Measurement.
+ */
+export type Measurement = keyof typeof Measurements
+
+/**
+ * Measurement options.
+ */
+export interface MeasurementOptions {
+ /**
+ * Set measurement median.
+ */
+ readonly median: boolean
+}
+
/**
* Worker choice strategy options.
*/
export interface WorkerChoiceStrategyOptions {
/**
- * Use tasks median run time instead of average run time.
+ * Number of worker choice retries to perform if no worker is eligible.
+ *
+ * @defaultValue 6
+ */
+ readonly retries?: number
+ /**
+ * Measurement to use in worker choice strategy supporting it.
+ */
+ readonly measurement?: Measurement
+ /**
+ * Runtime options.
+ *
+ * @defaultValue \{ median: false \}
+ */
+ readonly runTime?: MeasurementOptions
+ /**
+ * Wait time options.
+ *
+ * @defaultValue \{ median: false \}
+ */
+ readonly waitTime?: MeasurementOptions
+ /**
+ * Event loop utilization options.
*
- * @defaultValue false
+ * @defaultValue \{ median: false \}
*/
- medRunTime?: boolean
+ readonly elu?: MeasurementOptions
/**
- * Worker weights to use for weighted round robin worker selection strategy.
- * Weight is the tasks maximum average or median runtime in milliseconds.
+ * Worker weights to use for weighted round robin worker selection strategies.
+ * A weight is tasks maximum execution time in milliseconds for a worker node.
*
- * @defaultValue Computed worker weights automatically given the CPU performance.
+ * @defaultValue Weights computed automatically given the CPU performance.
*/
- weights?: Record<number, number>
+ readonly weights?: Record<number, number>
}
/**
- * Pool worker tasks usage statistics requirements.
+ * Measurement statistics requirements.
*
* @internal
*/
-export interface RequiredStatistics {
+export interface MeasurementStatisticsRequirements {
/**
- * Require tasks run time.
+ * Requires measurement aggregate.
*/
- runTime: boolean
+ aggregate: boolean
/**
- * Require tasks average run time.
+ * Requires measurement average.
*/
- avgRunTime: boolean
+ average: boolean
/**
- * Require tasks median run time.
+ * Requires measurement median.
*/
- medRunTime: boolean
+ median: boolean
+}
+
+/**
+ * Pool worker node worker usage statistics requirements.
+ *
+ * @internal
+ */
+export interface TaskStatisticsRequirements {
+ /**
+ * Tasks runtime requirements.
+ */
+ readonly runTime: MeasurementStatisticsRequirements
+ /**
+ * Tasks wait time requirements.
+ */
+ readonly waitTime: MeasurementStatisticsRequirements
+ /**
+ * Tasks event loop utilization requirements.
+ */
+ readonly elu: MeasurementStatisticsRequirements
+}
+
+/**
+ * Strategy policy.
+ *
+ * @internal
+ */
+export interface StrategyPolicy {
+ /**
+ * Expects tasks execution on the newly created dynamic worker.
+ */
+ readonly dynamicWorkerUsage: boolean
+ /**
+ * Expects the newly created dynamic worker to be flagged as ready.
+ */
+ readonly dynamicWorkerReady: boolean
}
/**
* Worker choice strategy interface.
+ *
+ * @internal
*/
export interface IWorkerChoiceStrategy {
/**
- * Required tasks usage statistics.
+ * Strategy policy.
+ */
+ readonly strategyPolicy: StrategyPolicy
+ /**
+ * Tasks statistics requirements.
*/
- readonly requiredStatistics: RequiredStatistics
+ readonly taskStatisticsRequirements: TaskStatisticsRequirements
/**
* Resets strategy internals.
*
* @returns `true` if the reset is successful, `false` otherwise.
*/
- reset: () => boolean
+ readonly reset: () => boolean
/**
* Updates the worker node key strategy internals.
*
* @returns `true` if the update is successful, `false` otherwise.
*/
- update: (workerNodeKey: number) => boolean
+ readonly update: (workerNodeKey: number) => boolean
/**
* Chooses a worker node in the pool and returns its key.
+ * If the worker node is not eligible, `undefined` is returned.
*
- * @returns The worker node key.
+ * @returns The worker node key or `undefined`.
*/
- choose: () => number
+ readonly choose: () => number | undefined
/**
* Removes the worker node key from strategy internals.
*
* @param workerNodeKey - The worker node key.
* @returns `true` if the worker node key is removed, `false` otherwise.
*/
- remove: (workerNodeKey: number) => boolean
+ readonly remove: (workerNodeKey: number) => boolean
/**
* Sets the worker choice strategy options.
*
* @param opts - The worker choice strategy options.
*/
- setOptions: (opts: WorkerChoiceStrategyOptions) => void
+ readonly setOptions: (opts: WorkerChoiceStrategyOptions) => void
}