perf: pre-instantiate worker choice strategies

[poolifier.git] / src / pools / selection-strategies / worker-choice-strategy-context.ts

diff --git a/src/pools/selection-strategies/worker-choice-strategy-context.ts b/src/pools/selection-strategies/worker-choice-strategy-context.ts
index 97d08682fcf1b62837912d0a3b283f03064e4d50..2d33738731c661e0df84a74a0ffa043e9e3b4e69 100644 (file)
--- a/src/pools/selection-strategies/worker-choice-strategy-context.ts
+++ b/src/pools/selection-strategies/worker-choice-strategy-context.ts
@@ -1,12 +1,16 @@
 import type { IPoolInternal } from '../pool-internal'
 import type { IPoolWorker } from '../pool-worker'
+import { FairShareWorkerChoiceStrategy } from './fair-share-worker-choice-strategy'
+import { LessBusyWorkerChoiceStrategy } from './less-busy-worker-choice-strategy'
+import { LessUsedWorkerChoiceStrategy } from './less-used-worker-choice-strategy'
+import { RoundRobinWorkerChoiceStrategy } from './round-robin-worker-choice-strategy'
 import type {
   IWorkerChoiceStrategy,
   RequiredStatistics,
   WorkerChoiceStrategy
 } from './selection-strategies-types'
 import { WorkerChoiceStrategies } from './selection-strategies-types'
-import { getWorkerChoiceStrategy } from './selection-strategies-utils'
+import { WeightedRoundRobinWorkerChoiceStrategy } from './weighted-round-robin-worker-choice-strategy'
 
 /**
  * The worker choice strategy context.
@@ -20,7 +24,10 @@ export class WorkerChoiceStrategyContext<
   Data = unknown,
   Response = unknown
 > {
-  private workerChoiceStrategy: IWorkerChoiceStrategy<Worker, Data, Response>
+  private readonly workerChoiceStrategies: Map<
+  WorkerChoiceStrategy,
+  IWorkerChoiceStrategy<Worker, Data, Response>
+  >
 
   /**
    * Worker choice strategy context constructor.
@@ -35,19 +42,44 @@ export class WorkerChoiceStrategyContext<
     private workerChoiceStrategyType: WorkerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN
   ) {
     this.execute.bind(this)
-    this.workerChoiceStrategy = getWorkerChoiceStrategy<Worker, Data, Response>(
-      pool,
-      this.workerChoiceStrategyType
-    )
+    this.workerChoiceStrategies = new Map<
+    WorkerChoiceStrategy,
+    IWorkerChoiceStrategy<Worker, Data, Response>
+    >([
+      [
+        WorkerChoiceStrategies.ROUND_ROBIN,
+        new RoundRobinWorkerChoiceStrategy<Worker, Data, Response>(pool)
+      ],
+      [
+        WorkerChoiceStrategies.LESS_USED,
+        new LessUsedWorkerChoiceStrategy<Worker, Data, Response>(pool)
+      ],
+      [
+        WorkerChoiceStrategies.LESS_BUSY,
+        new LessBusyWorkerChoiceStrategy<Worker, Data, Response>(pool)
+      ],
+      [
+        WorkerChoiceStrategies.FAIR_SHARE,
+        new FairShareWorkerChoiceStrategy<Worker, Data, Response>(pool)
+      ],
+      [
+        WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN,
+        new WeightedRoundRobinWorkerChoiceStrategy<Worker, Data, Response>(pool)
+      ]
+    ])
   }
 
   /**
-   * Gets the worker choice strategy required statistics.
+   * Gets the worker choice strategy in the context required statistics.
    *
    * @returns The required statistics.
    */
   public getRequiredStatistics (): RequiredStatistics {
-    return this.workerChoiceStrategy.requiredStatistics
+    return (
+      this.workerChoiceStrategies.get(
+        this.workerChoiceStrategyType
+      ) as IWorkerChoiceStrategy<Worker, Data, Response>
+    ).requiredStatistics
   }
 
   /**
@@ -60,40 +92,42 @@ export class WorkerChoiceStrategyContext<
     workerChoiceStrategy: WorkerChoiceStrategy
   ): void {
     if (this.workerChoiceStrategyType === workerChoiceStrategy) {
-      this.workerChoiceStrategy?.reset()
+      this.workerChoiceStrategies.get(workerChoiceStrategy)?.reset()
     } else {
       this.workerChoiceStrategyType = workerChoiceStrategy
-      this.workerChoiceStrategy = getWorkerChoiceStrategy<
-      Worker,
-      Data,
-      Response
-      >(pool, this.workerChoiceStrategyType)
     }
   }
 
   /**
-   * Chooses a worker with the worker choice strategy.
+   * Executes the worker choice strategy algorithm in the context.
    *
    * @returns The key of the chosen one.
    */
   public execute (): number {
+    const workerChoiceStrategy = this.workerChoiceStrategies.get(
+      this.workerChoiceStrategyType
+    ) as IWorkerChoiceStrategy<Worker, Data, Response>
     if (
-      this.workerChoiceStrategy.isDynamicPool &&
-      !this.workerChoiceStrategy.pool.full &&
-      this.workerChoiceStrategy.pool.findFreeWorkerKey() === -1
+      workerChoiceStrategy.isDynamicPool &&
+      !workerChoiceStrategy.pool.full &&
+      workerChoiceStrategy.pool.findFreeWorkerKey() === -1
     ) {
       return this.createWorkerCallback()
     }
-    return this.workerChoiceStrategy.choose()
+    return workerChoiceStrategy.choose()
   }
 
   /**
-   * Removes a worker in the worker choice strategy internals.
+   * Removes a worker from the worker choice strategy in the context.
    *
    * @param workerKey - The key of the worker to remove.
    * @returns `true` if the removal is successful, `false` otherwise.
    */
   public remove (workerKey: number): boolean {
-    return this.workerChoiceStrategy.remove(workerKey)
+    return (
+      this.workerChoiceStrategies.get(
+        this.workerChoiceStrategyType
+      ) as IWorkerChoiceStrategy<Worker, Data, Response>
+    ).remove(workerKey)
   }
 }