refactor: factor out common code in worker choice strategies

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

diff --git a/src/pools/selection-strategies/abstract-worker-choice-strategy.ts b/src/pools/selection-strategies/abstract-worker-choice-strategy.ts
index 7eced8d5985cf5f40c7b02b385b47628ed8c7154..6e798fbc4349d98bf5b5761d884013382efa601f 100644 (file)
--- a/src/pools/selection-strategies/abstract-worker-choice-strategy.ts
+++ b/src/pools/selection-strategies/abstract-worker-choice-strategy.ts
@@ -1,5 +1,6 @@
+import { cpus } from 'node:os'
 import { DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS } from '../../utils'
-import { PoolType, type IPool } from '../pool'
+import type { IPool } from '../pool'
 import type { IWorker } from '../worker'
 import type {
   IWorkerChoiceStrategy,
@@ -24,12 +25,13 @@ export abstract class AbstractWorkerChoiceStrategy<
    */
   private toggleFindLastFreeWorkerNodeKey: boolean = false
   /** @inheritDoc */
-  protected readonly isDynamicPool: boolean
-  /** @inheritDoc */
   public readonly requiredStatistics: RequiredStatistics = {
     runTime: false,
     avgRunTime: false,
-    medRunTime: false
+    medRunTime: false,
+    waitTime: false,
+    avgWaitTime: false,
+    medWaitTime: false
   }
 
   /**
@@ -42,11 +44,10 @@ export abstract class AbstractWorkerChoiceStrategy<
     protected readonly pool: IPool<Worker, Data, Response>,
     protected opts: WorkerChoiceStrategyOptions = DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
   ) {
-    this.isDynamicPool = this.pool.type === PoolType.DYNAMIC
     this.choose = this.choose.bind(this)
   }
 
-  protected checkOptions (opts: WorkerChoiceStrategyOptions): void {
+  protected setRequiredStatistics (opts: WorkerChoiceStrategyOptions): void {
     if (this.requiredStatistics.avgRunTime && opts.medRunTime === true) {
       this.requiredStatistics.avgRunTime = false
       this.requiredStatistics.medRunTime = opts.medRunTime as boolean
@@ -55,11 +56,22 @@ export abstract class AbstractWorkerChoiceStrategy<
       this.requiredStatistics.avgRunTime = true
       this.requiredStatistics.medRunTime = opts.medRunTime as boolean
     }
+    if (this.requiredStatistics.avgWaitTime && opts.medWaitTime === true) {
+      this.requiredStatistics.avgWaitTime = false
+      this.requiredStatistics.medWaitTime = opts.medWaitTime as boolean
+    }
+    if (this.requiredStatistics.medWaitTime && opts.medWaitTime === false) {
+      this.requiredStatistics.avgWaitTime = true
+      this.requiredStatistics.medWaitTime = opts.medWaitTime as boolean
+    }
   }
 
   /** @inheritDoc */
   public abstract reset (): boolean
 
+  /** @inheritDoc */
+  public abstract update (workerNodeKey: number): boolean
+
   /** @inheritDoc */
   public abstract choose (): number
 
@@ -69,7 +81,7 @@ export abstract class AbstractWorkerChoiceStrategy<
   /** @inheritDoc */
   public setOptions (opts: WorkerChoiceStrategyOptions): void {
     opts = opts ?? DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
-    this.checkOptions(opts)
+    this.setRequiredStatistics(opts)
     this.opts = opts
   }
 
@@ -87,6 +99,45 @@ export abstract class AbstractWorkerChoiceStrategy<
     return this.findFirstFreeWorkerNodeKey()
   }
 
+  /**
+   * Gets the worker task runtime.
+   * If the required statistics are `avgRunTime`, the average runtime is returned.
+   * If the required statistics are `medRunTime`, the median runtime is returned.
+   *
+   * @param workerNodeKey - The worker node key.
+   * @returns The worker task runtime.
+   */
+  protected getWorkerTaskRunTime (workerNodeKey: number): number {
+    return this.requiredStatistics.medRunTime
+      ? this.pool.workerNodes[workerNodeKey].tasksUsage.medRunTime
+      : this.pool.workerNodes[workerNodeKey].tasksUsage.avgRunTime
+  }
+
+  /**
+   * Gets the worker task wait time.
+   * If the required statistics are `avgWaitTime`, the average wait time is returned.
+   * If the required statistics are `medWaitTime`, the median wait time is returned.
+   *
+   * @param workerNodeKey - The worker node key.
+   * @returns The worker task wait time.
+   */
+  protected getWorkerWaitTime (workerNodeKey: number): number {
+    return this.requiredStatistics.medWaitTime
+      ? this.pool.workerNodes[workerNodeKey].tasksUsage.medWaitTime
+      : this.pool.workerNodes[workerNodeKey].tasksUsage.avgWaitTime
+  }
+
+  protected computeDefaultWorkerWeight (): number {
+    let cpusCycleTimeWeight = 0
+    for (const cpu of cpus()) {
+      // CPU estimated cycle time
+      const numberOfDigits = cpu.speed.toString().length - 1
+      const cpuCycleTime = 1 / (cpu.speed / Math.pow(10, numberOfDigits))
+      cpusCycleTimeWeight += cpuCycleTime * Math.pow(10, numberOfDigits)
+    }
+    return Math.round(cpusCycleTimeWeight / cpus().length)
+  }
+
   /**
    * Finds the first free worker node key based on the number of tasks the worker has applied.
    *
@@ -98,7 +149,7 @@ export abstract class AbstractWorkerChoiceStrategy<
    */
   private findFirstFreeWorkerNodeKey (): number {
     return this.pool.workerNodes.findIndex(workerNode => {
-      return workerNode.tasksUsage?.running === 0
+      return workerNode.tasksUsage.running === 0
     })
   }
 
@@ -112,13 +163,17 @@ export abstract class AbstractWorkerChoiceStrategy<
    * @returns A worker node key if there is one, `-1` otherwise.
    */
   private findLastFreeWorkerNodeKey (): number {
-    // It requires node >= 18.0.0
+    // It requires node >= 18.0.0:
     // return this.workerNodes.findLastIndex(workerNode => {
-    //   return workerNode.tasksUsage?.running === 0
+    //   return workerNode.tasksUsage.running === 0
     // })
-    for (let i = this.pool.workerNodes.length - 1; i >= 0; i--) {
-      if (this.pool.workerNodes[i].tasksUsage?.running === 0) {
-        return i
+    for (
+      let workerNodeKey = this.pool.workerNodes.length - 1;
+      workerNodeKey >= 0;
+      workerNodeKey--
+    ) {
+      if (this.pool.workerNodes[workerNodeKey].tasksUsage.running === 0) {
+        return workerNodeKey
       }
     }
     return -1