feat: add tasks wait time account per worker
[poolifier.git] / src / pools / selection-strategies / fair-share-worker-choice-strategy.ts
index 81944f7a6c1d0342889b716a26be5b23cc34034e..56d9dc361fe6e70255877ec6c1e6be6f33b70a70 100644 (file)
@@ -8,14 +8,6 @@ import type {
   WorkerChoiceStrategyOptions
 } from './selection-strategies-types'
 
-/**
- * Worker virtual task timestamp.
- */
-interface WorkerVirtualTaskTimestamp {
-  start: number
-  end: number
-}
-
 /**
  * Selects the next worker with a fair share scheduling algorithm.
  * Loosely modeled after the fair queueing algorithm: https://en.wikipedia.org/wiki/Fair_queuing.
@@ -35,16 +27,16 @@ export class FairShareWorkerChoiceStrategy<
   public readonly requiredStatistics: RequiredStatistics = {
     runTime: true,
     avgRunTime: true,
-    medRunTime: false
+    medRunTime: false,
+    waitTime: false,
+    avgWaitTime: false,
+    medWaitTime: false
   }
 
   /**
-   * Worker last virtual task execution timestamp.
+   * Workers' virtual task end execution timestamp.
    */
-  private readonly workerLastVirtualTaskTimestamp: Map<
-  number,
-  WorkerVirtualTaskTimestamp
-  > = new Map<number, WorkerVirtualTaskTimestamp>()
+  private workersVirtualTaskEndTimestamp: number[] = []
 
   /** @inheritDoc */
   public constructor (
@@ -52,12 +44,18 @@ export class FairShareWorkerChoiceStrategy<
     opts: WorkerChoiceStrategyOptions = DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
   ) {
     super(pool, opts)
-    this.checkOptions(opts)
+    this.setRequiredStatistics(this.opts)
   }
 
   /** @inheritDoc */
   public reset (): boolean {
-    this.workerLastVirtualTaskTimestamp.clear()
+    this.workersVirtualTaskEndTimestamp = []
+    return true
+  }
+
+  /** @inheritDoc */
+  public update (workerNodeKey: number): boolean {
+    this.computeWorkerVirtualTaskEndTimestamp(workerNodeKey)
     return true
   }
 
@@ -65,15 +63,15 @@ export class FairShareWorkerChoiceStrategy<
   public choose (): number {
     let minWorkerVirtualTaskEndTimestamp = Infinity
     let chosenWorkerNodeKey!: number
-    for (const [index] of this.pool.workerNodes.entries()) {
-      this.computeWorkerLastVirtualTaskTimestamp(index)
-      const workerLastVirtualTaskEndTimestamp =
-        this.workerLastVirtualTaskTimestamp.get(index)?.end ?? 0
-      if (
-        workerLastVirtualTaskEndTimestamp < minWorkerVirtualTaskEndTimestamp
-      ) {
-        minWorkerVirtualTaskEndTimestamp = workerLastVirtualTaskEndTimestamp
-        chosenWorkerNodeKey = index
+    for (const [workerNodeKey] of this.pool.workerNodes.entries()) {
+      if (this.workersVirtualTaskEndTimestamp[workerNodeKey] == null) {
+        this.computeWorkerVirtualTaskEndTimestamp(workerNodeKey)
+      }
+      const workerVirtualTaskEndTimestamp =
+        this.workersVirtualTaskEndTimestamp[workerNodeKey]
+      if (workerVirtualTaskEndTimestamp < minWorkerVirtualTaskEndTimestamp) {
+        minWorkerVirtualTaskEndTimestamp = workerVirtualTaskEndTimestamp
+        chosenWorkerNodeKey = workerNodeKey
       }
     }
     return chosenWorkerNodeKey
@@ -81,31 +79,36 @@ export class FairShareWorkerChoiceStrategy<
 
   /** @inheritDoc */
   public remove (workerNodeKey: number): boolean {
-    const deleted = this.workerLastVirtualTaskTimestamp.delete(workerNodeKey)
-    for (const [key, value] of this.workerLastVirtualTaskTimestamp.entries()) {
-      if (key > workerNodeKey) {
-        this.workerLastVirtualTaskTimestamp.set(key - 1, value)
-      }
-    }
-    return deleted
+    this.workersVirtualTaskEndTimestamp.splice(workerNodeKey, 1)
+    return true
   }
 
   /**
-   * Computes worker last virtual task timestamp.
+   * Computes the worker node key virtual task end timestamp.
    *
    * @param workerNodeKey - The worker node key.
    */
-  private computeWorkerLastVirtualTaskTimestamp (workerNodeKey: number): void {
-    const workerVirtualTaskStartTimestamp = Math.max(
+  private computeWorkerVirtualTaskEndTimestamp (workerNodeKey: number): void {
+    this.workersVirtualTaskEndTimestamp[workerNodeKey] =
+      this.getWorkerVirtualTaskEndTimestamp(
+        workerNodeKey,
+        this.getWorkerVirtualTaskStartTimestamp(workerNodeKey)
+      )
+  }
+
+  private getWorkerVirtualTaskEndTimestamp (
+    workerNodeKey: number,
+    workerVirtualTaskStartTimestamp: number
+  ): number {
+    return (
+      workerVirtualTaskStartTimestamp + this.getWorkerTaskRunTime(workerNodeKey)
+    )
+  }
+
+  private getWorkerVirtualTaskStartTimestamp (workerNodeKey: number): number {
+    return Math.max(
       performance.now(),
-      this.workerLastVirtualTaskTimestamp.get(workerNodeKey)?.end ?? -Infinity
+      this.workersVirtualTaskEndTimestamp[workerNodeKey] ?? -Infinity
     )
-    const workerVirtualTaskTRunTime = this.requiredStatistics.medRunTime
-      ? this.pool.workerNodes[workerNodeKey].tasksUsage.medRunTime
-      : this.pool.workerNodes[workerNodeKey].tasksUsage.avgRunTime
-    this.workerLastVirtualTaskTimestamp.set(workerNodeKey, {
-      start: workerVirtualTaskStartTimestamp,
-      end: workerVirtualTaskStartTimestamp + (workerVirtualTaskTRunTime ?? 0)
-    })
   }
 }