fix: ensure worker choice is retried at least the pool max size

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

diff --git a/src/pools/selection-strategies/least-elu-worker-choice-strategy.ts b/src/pools/selection-strategies/least-elu-worker-choice-strategy.ts
index fbbd48e3c918568b3c493a8cff4e4044a67106bc..d81f206481262eb33eeb0cf77cbeb803073b7855 100644 (file)
--- a/src/pools/selection-strategies/least-elu-worker-choice-strategy.ts
+++ b/src/pools/selection-strategies/least-elu-worker-choice-strategy.ts
@@ -1,19 +1,19 @@
-import { DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS } from '../../utils'
+import { DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS } from '../../utils'
 import type { IPool } from '../pool'
 import type { IWorker } from '../worker'
 import { AbstractWorkerChoiceStrategy } from './abstract-worker-choice-strategy'
 import type {
   IWorkerChoiceStrategy,
-  TaskStatisticsRequirements,
-  WorkerChoiceStrategyOptions
+  InternalWorkerChoiceStrategyOptions,
+  TaskStatisticsRequirements
 } from './selection-strategies-types'
 
 /**
  * Selects the worker with the least ELU.
  *
  * @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 execution response. This can only be serializable data.
+ * @typeParam Data - Type of data sent to the worker. This can only be structured-cloneable data.
+ * @typeParam Response - Type of execution response. This can only be structured-cloneable data.
  */
 export class LeastEluWorkerChoiceStrategy<
     Worker extends IWorker,
@@ -24,22 +24,22 @@ export class LeastEluWorkerChoiceStrategy<
   implements IWorkerChoiceStrategy {
   /** @inheritDoc */
   public readonly taskStatisticsRequirements: TaskStatisticsRequirements = {
-    runTime: false,
-    avgRunTime: false,
-    medRunTime: false,
-    waitTime: false,
-    avgWaitTime: false,
-    medWaitTime: false,
-    elu: true
+    runTime: DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS,
+    waitTime: DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS,
+    elu: {
+      aggregate: true,
+      average: false,
+      median: false
+    }
   }
 
   /** @inheritDoc */
   public constructor (
     pool: IPool<Worker, Data, Response>,
-    opts: WorkerChoiceStrategyOptions = DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
+    opts: InternalWorkerChoiceStrategyOptions
   ) {
     super(pool, opts)
-    this.setTaskStatistics(this.opts)
+    this.setTaskStatisticsRequirements(this.opts)
   }
 
   /** @inheritDoc */
@@ -53,24 +53,27 @@ export class LeastEluWorkerChoiceStrategy<
   }
 
   /** @inheritDoc */
-  public choose (): number {
-    let minWorkerElu = Infinity
-    let leastEluWorkerNodeKey!: number
-    for (const [workerNodeKey, workerNode] of this.pool.workerNodes.entries()) {
-      const workerUsage = workerNode.workerUsage
-      const workerElu = workerUsage.elu?.utilization ?? 0
-      if (workerElu === 0) {
-        return workerNodeKey
-      } else if (workerElu < minWorkerElu) {
-        minWorkerElu = workerElu
-        leastEluWorkerNodeKey = workerNodeKey
-      }
-    }
-    return leastEluWorkerNodeKey
+  public choose (): number | undefined {
+    this.setPreviousWorkerNodeKey(this.nextWorkerNodeKey)
+    this.nextWorkerNodeKey = this.leastEluNextWorkerNodeKey()
+    return this.nextWorkerNodeKey
   }
 
   /** @inheritDoc */
   public remove (): boolean {
     return true
   }
+
+  private leastEluNextWorkerNodeKey (): number | undefined {
+    return this.pool.workerNodes.reduce(
+      (minWorkerNodeKey, workerNode, workerNodeKey, workerNodes) => {
+        return this.isWorkerNodeReady(workerNodeKey) &&
+          (workerNode.usage.elu.active.aggregate ?? 0) <
+            (workerNodes[minWorkerNodeKey].usage.elu.active.aggregate ?? 0)
+          ? workerNodeKey
+          : minWorkerNodeKey
+      },
+      0
+    )
+  }
 }