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  * Worker choice strategy options.
  40  */
  41 export interface WorkerChoiceStrategyOptions {
  42   /**
  43    * Use tasks median runtime instead of average runtime.
  44    *
  45    * @defaultValue false
  46    */
  47   medRunTime?: boolean
  48   /**
  49    * Use tasks median wait time instead of average runtime.
  50    *
  51    * @defaultValue false
  52    */
  53   medWaitTime?: boolean
  54   /**
  55    * Worker weights to use for weighted round robin worker selection strategy.
  56    * Weight is the tasks maximum average or median runtime in milliseconds.
  57    *
  58    * @defaultValue Computed worker weights automatically given the CPU performance.
  59    */
  60   weights?: Record<number, number>
  61 }
  62
  63 /**
  64  * Pool worker tasks usage statistics requirements.
  65  *
  66  * @internal
  67  */
  68 export interface RequiredStatistics {
  69   /**
  70    * Require tasks runtime.
  71    */
  72   runTime: boolean
  73   /**
  74    * Require tasks average runtime.
  75    */
  76   avgRunTime: boolean
  77   /**
  78    * Require tasks median runtime.
  79    */
  80   medRunTime: boolean
  81   /**
  82    * Require tasks wait time.
  83    */
  84   waitTime: boolean
  85   /**
  86    * Require tasks average wait time.
  87    */
  88   avgWaitTime: boolean
  89   /**
  90    * Require tasks median wait time.
  91    */
  92   medWaitTime: boolean
  93   /**
  94    * Event loop utilization.
  95    */
  96   elu: boolean
  97 }
  98
  99 /**
 100  * Worker choice strategy interface.
 101  */
 102 export interface IWorkerChoiceStrategy {
 103   /**
 104    * Required tasks usage statistics.
 105    */
 106   readonly requiredStatistics: RequiredStatistics
 107   /**
 108    * Resets strategy internals.
 109    *
 110    * @returns `true` if the reset is successful, `false` otherwise.
 111    */
 112   reset: () => boolean
 113   /**
 114    * Updates the worker node key strategy internals.
 115    *
 116    * @returns `true` if the update is successful, `false` otherwise.
 117    */
 118   update: (workerNodeKey: number) => boolean
 119   /**
 120    * Chooses a worker node in the pool and returns its key.
 121    *
 122    * @returns The worker node key.
 123    */
 124   choose: () => number
 125   /**
 126    * Removes the worker node key from strategy internals.
 127    *
 128    * @param workerNodeKey - The worker node key.
 129    * @returns `true` if the worker node key is removed, `false` otherwise.
 130    */
 131   remove: (workerNodeKey: number) => boolean
 132   /**
 133    * Sets the worker choice strategy options.
 134    *
 135    * @param opts - The worker choice strategy options.
 136    */
 137   setOptions: (opts: WorkerChoiceStrategyOptions) => void
 138 }