fix: ensure worker choice is retried at least the pool max size
[poolifier.git] / src / pools / selection-strategies / least-elu-worker-choice-strategy.ts
index 03e6ca0448e108b919cdd4912a74a61edc719995..d81f206481262eb33eeb0cf77cbeb803073b7855 100644 (file)
@@ -1,14 +1,11 @@
-import {
-  DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS,
-  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'
 
 /**
@@ -39,7 +36,7 @@ export class LeastEluWorkerChoiceStrategy<
   /** @inheritDoc */
   public constructor (
     pool: IPool<Worker, Data, Response>,
-    opts: WorkerChoiceStrategyOptions = DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
+    opts: InternalWorkerChoiceStrategyOptions
   ) {
     super(pool, opts)
     this.setTaskStatisticsRequirements(this.opts)
@@ -56,8 +53,10 @@ export class LeastEluWorkerChoiceStrategy<
   }
 
   /** @inheritDoc */
-  public choose (): number {
-    return this.leastEluNextWorkerNodeKey()
+  public choose (): number | undefined {
+    this.setPreviousWorkerNodeKey(this.nextWorkerNodeKey)
+    this.nextWorkerNodeKey = this.leastEluNextWorkerNodeKey()
+    return this.nextWorkerNodeKey
   }
 
   /** @inheritDoc */
@@ -65,22 +64,16 @@ export class LeastEluWorkerChoiceStrategy<
     return true
   }
 
-  private leastEluNextWorkerNodeKey (): number {
-    let minWorkerElu = Infinity
-    for (const [workerNodeKey, workerNode] of this.pool.workerNodes.entries()) {
-      const workerUsage = workerNode.usage
-      const workerElu = workerUsage.elu?.active?.aggregate ?? 0
-      if (this.isWorkerNodeEligible(workerNodeKey) && workerElu === 0) {
-        this.nextWorkerNodeKey = workerNodeKey
-        break
-      } else if (
-        this.isWorkerNodeEligible(workerNodeKey) &&
-        workerElu < minWorkerElu
-      ) {
-        minWorkerElu = workerElu
-        this.nextWorkerNodeKey = workerNodeKey
-      }
-    }
-    return this.nextWorkerNodeKey
+  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
+    )
   }
 }