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