src/pools/selection-strategies/selection-strategies-types.ts

   1 /**
   2  * Enumeration of worker choice strategies.
   3  */
   4 export const WorkerChoiceStrategies = Object.freeze({
   5   /**
   6    * Round robin worker selection strategy.
   7    */
   8   ROUND_ROBIN: 'ROUND_ROBIN',
   9   /**
  10    * Least used worker selection strategy.
  11    */
  12   LEAST_USED: 'LEAST_USED',
  13   /**
  14    * Least busy worker selection strategy.
  15    */
  16   LEAST_BUSY: 'LEAST_BUSY',
  17   /**
  18    * Fair share worker selection strategy.
  19    */
  20   FAIR_SHARE: 'FAIR_SHARE',
  21   /**
  22    * Weighted round robin worker selection strategy.
  23    */
  24   WEIGHTED_ROUND_ROBIN: 'WEIGHTED_ROUND_ROBIN',
  25   /**
  26    * Interleaved weighted round robin worker selection strategy.
  27    *
  28    * @experimental
  29    */
  30   INTERLEAVED_WEIGHTED_ROUND_ROBIN: 'INTERLEAVED_WEIGHTED_ROUND_ROBIN'
  31 } as const)
  32
  33 /**
  34  * Worker choice strategy.
  35  */
  36 export type WorkerChoiceStrategy = keyof typeof WorkerChoiceStrategies
  37
  38 /**
  39  * Measurement options.
  40  */
  41 interface MeasurementOptions {
  42   /**
  43    * Set measurement median.
  44    */
  45   median: boolean
  46 }
  47
  48 /**
  49  * Worker choice strategy options.
  50  */
  51 export interface WorkerChoiceStrategyOptions {
  52   /**
  53    * Runtime options.
  54    *
  55    * @defaultValue \{ median: false \}
  56    */
  57   runTime?: MeasurementOptions
  58   /**
  59    * Wait time options.
  60    *
  61    * @defaultValue \{ median: false \}
  62    */
  63   waitTime?: MeasurementOptions
  64   /**
  65    * Worker weights to use for weighted round robin worker selection strategy.
  66    * Weight is the tasks maximum average or median runtime in milliseconds.
  67    *
  68    * @defaultValue Computed worker weights automatically given the CPU performance.
  69    */
  70   weights?: Record<number, number>
  71 }
  72
  73 /**
  74  * Measurement statistics requirements.
  75  *
  76  * @internal
  77  */
  78 interface MeasurementStatisticsRequirements {
  79   /**
  80    * Require measurement aggregate.
  81    */
  82   aggregate: boolean
  83   /**
  84    * Require measurement average.
  85    */
  86   average: boolean
  87   /**
  88    * Require measurement median.
  89    */
  90   median: boolean
  91 }
  92
  93 /**
  94  * Pool worker node worker usage statistics requirements.
  95  *
  96  * @internal
  97  */
  98 export interface TaskStatisticsRequirements {
  99   /**
 100    * Tasks runtime requirements.
 101    */
 102   runTime: MeasurementStatisticsRequirements
 103   /**
 104    * Tasks wait time requirements.
 105    */
 106   waitTime: MeasurementStatisticsRequirements
 107   /**
 108    * Event loop utilization.
 109    */
 110   elu: boolean
 111 }
 112
 113 /**
 114  * Worker choice strategy interface.
 115  */
 116 export interface IWorkerChoiceStrategy {
 117   /**
 118    * Tasks statistics requirements.
 119    */
 120   readonly taskStatisticsRequirements: TaskStatisticsRequirements
 121   /**
 122    * Resets strategy internals.
 123    *
 124    * @returns `true` if the reset is successful, `false` otherwise.
 125    */
 126   reset: () => boolean
 127   /**
 128    * Updates the worker node key strategy internals.
 129    *
 130    * @returns `true` if the update is successful, `false` otherwise.
 131    */
 132   update: (workerNodeKey: number) => boolean
 133   /**
 134    * Chooses a worker node in the pool and returns its key.
 135    *
 136    * @returns The worker node key.
 137    */
 138   choose: () => number
 139   /**
 140    * Removes the worker node key from strategy internals.
 141    *
 142    * @param workerNodeKey - The worker node key.
 143    * @returns `true` if the worker node key is removed, `false` otherwise.
 144    */
 145   remove: (workerNodeKey: number) => boolean
 146   /**
 147    * Sets the worker choice strategy options.
 148    *
 149    * @param opts - The worker choice strategy options.
 150    */
 151   setOptions: (opts: WorkerChoiceStrategyOptions) => void
 152 }