fix: fix fair share algorithm implementation

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

diff --git a/src/pools/selection-strategies/fair-share-worker-choice-strategy.ts b/src/pools/selection-strategies/fair-share-worker-choice-strategy.ts
index f8427d01bab393ae47c9d6975d31e14338f5c74d..e65575a1e05c805978111cbbf279c5f5a5767e6f 100644 (file)
--- a/src/pools/selection-strategies/fair-share-worker-choice-strategy.ts
+++ b/src/pools/selection-strategies/fair-share-worker-choice-strategy.ts
@@ -1,8 +1,11 @@
-import type { IPoolWorker } from '../pool-worker'
+import { DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS } from '../../utils'
+import type { IPool } from '../pool'
+import type { IWorker } from '../worker'
 import { AbstractWorkerChoiceStrategy } from './abstract-worker-choice-strategy'
 import type {
   IWorkerChoiceStrategy,
-  RequiredStatistics
+  RequiredStatistics,
+  WorkerChoiceStrategyOptions
 } from './selection-strategies-types'
 
 /**
@@ -10,7 +13,7 @@ import type {
  */
 interface WorkerVirtualTaskTimestamp {
   start: number
-  end: number
+  end?: number
 }
 
 /**
@@ -19,79 +22,85 @@ interface WorkerVirtualTaskTimestamp {
  *
  * @typeParam Worker - Type of worker which manages the strategy.
  * @typeParam Data - Type of data sent to the worker. This can only be serializable data.
- * @typeParam Response - Type of response of execution. This can only be serializable data.
+ * @typeParam Response - Type of execution response. This can only be serializable data.
  */
 export class FairShareWorkerChoiceStrategy<
-    Worker extends IPoolWorker,
+    Worker extends IWorker,
     Data = unknown,
     Response = unknown
   >
   extends AbstractWorkerChoiceStrategy<Worker, Data, Response>
-  implements IWorkerChoiceStrategy<Worker, Data, Response> {
+  implements IWorkerChoiceStrategy {
   /** @inheritDoc */
   public readonly requiredStatistics: RequiredStatistics = {
     runTime: true,
-    avgRunTime: true
+    avgRunTime: true,
+    medRunTime: false
   }
 
   /**
-   *  Worker last virtual task execution timestamp.
+   * Workers' virtual task execution timestamp.
    */
-  private readonly workerLastVirtualTaskTimestamp: Map<
-  number,
-  WorkerVirtualTaskTimestamp
-  > = new Map<number, WorkerVirtualTaskTimestamp>()
+  private workersVirtualTaskTimestamp: WorkerVirtualTaskTimestamp[] = []
+
+  /** @inheritDoc */
+  public constructor (
+    pool: IPool<Worker, Data, Response>,
+    opts: WorkerChoiceStrategyOptions = DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
+  ) {
+    super(pool, opts)
+    this.checkOptions(this.opts)
+  }
 
   /** @inheritDoc */
   public reset (): boolean {
-    this.workerLastVirtualTaskTimestamp.clear()
+    this.workersVirtualTaskTimestamp = []
+    return true
+  }
+
+  /** @inheritDoc */
+  public update (workerNodeKey: number): boolean {
+    this.computeWorkerVirtualTaskTimestamp(workerNodeKey)
     return true
   }
 
   /** @inheritDoc */
   public choose (): number {
     let minWorkerVirtualTaskEndTimestamp = Infinity
-    let chosenWorkerKey!: number
-    for (const [index] of this.pool.workers.entries()) {
-      this.computeWorkerLastVirtualTaskTimestamp(index)
-      const workerLastVirtualTaskEndTimestamp =
-        this.workerLastVirtualTaskTimestamp.get(index)?.end ?? 0
-      if (
-        workerLastVirtualTaskEndTimestamp < minWorkerVirtualTaskEndTimestamp
-      ) {
-        minWorkerVirtualTaskEndTimestamp = workerLastVirtualTaskEndTimestamp
-        chosenWorkerKey = index
+    let chosenWorkerNodeKey!: number
+    for (const [workerNodeKey] of this.pool.workerNodes.entries()) {
+      const workerVirtualTaskEndTimestamp =
+        this.workersVirtualTaskTimestamp[workerNodeKey]?.end ?? 0
+      if (workerVirtualTaskEndTimestamp < minWorkerVirtualTaskEndTimestamp) {
+        minWorkerVirtualTaskEndTimestamp = workerVirtualTaskEndTimestamp
+        chosenWorkerNodeKey = workerNodeKey
       }
     }
-    return chosenWorkerKey
+    return chosenWorkerNodeKey
   }
 
   /** @inheritDoc */
-  public remove (workerKey: number): boolean {
-    const workerDeleted = this.workerLastVirtualTaskTimestamp.delete(workerKey)
-    for (const [key, value] of this.workerLastVirtualTaskTimestamp.entries()) {
-      if (key > workerKey) {
-        this.workerLastVirtualTaskTimestamp.set(key - 1, value)
-      }
-    }
-    return workerDeleted
+  public remove (workerNodeKey: number): boolean {
+    this.workersVirtualTaskTimestamp.splice(workerNodeKey, 1)
+    return true
   }
 
   /**
-   * Computes worker last virtual task timestamp.
+   * Computes worker virtual task timestamp.
    *
-   * @param workerKey - The worker key.
+   * @param workerNodeKey - The worker node key.
    */
-  private computeWorkerLastVirtualTaskTimestamp (workerKey: number): void {
+  private computeWorkerVirtualTaskTimestamp (workerNodeKey: number): void {
     const workerVirtualTaskStartTimestamp = Math.max(
-      Date.now(),
-      this.workerLastVirtualTaskTimestamp.get(workerKey)?.end ?? -Infinity
+      performance.now(),
+      this.workersVirtualTaskTimestamp[workerNodeKey]?.end ?? -Infinity
     )
-    this.workerLastVirtualTaskTimestamp.set(workerKey, {
+    const workerVirtualTaskTRunTime = this.requiredStatistics.medRunTime
+      ? this.pool.workerNodes[workerNodeKey].tasksUsage.medRunTime
+      : this.pool.workerNodes[workerNodeKey].tasksUsage.avgRunTime
+    this.workersVirtualTaskTimestamp[workerNodeKey] = {
       start: workerVirtualTaskStartTimestamp,
-      end:
-        workerVirtualTaskStartTimestamp +
-        (this.pool.workers[workerKey].tasksUsage.avgRunTime ?? 0)
-    })
+      end: workerVirtualTaskStartTimestamp + workerVirtualTaskTRunTime
+    }
   }
 }