From f6392d503f33ca42d5125f9b524fd9454b87fbba Mon Sep 17 00:00:00 2001
From: =?utf8?q?J=C3=A9r=C3=B4me=20Benoit?= <jerome.benoit@piment-noir.org>
Date: Sun, 6 Jul 2025 22:13:37 +0200
Subject: [PATCH] fix: fix worker usage statistics computation
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Signed-off-by: Jérôme Benoit <jerome.benoit@piment-noir.org>
---
 src/pools/utils.ts  | 17 +++++++----------
 src/pools/worker.ts |  1 +
 2 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/src/pools/utils.ts b/src/pools/utils.ts
index 3b9ecaddd..025402749 100644
--- a/src/pools/utils.ts
+++ b/src/pools/utils.ts
@@ -272,14 +272,14 @@ const updateMeasurementStatistics = (
           measurementStatistics.history.toArray()
         )
       } else if (measurementStatistics.average != null) {
-        delete measurementStatistics.average
+        measurementStatistics.average = undefined
       }
       if (measurementRequirements.median) {
         measurementStatistics.median = median(
           measurementStatistics.history.toArray()
         )
       } else if (measurementStatistics.median != null) {
-        delete measurementStatistics.median
+        measurementStatistics.median = undefined
       }
     }
   }
@@ -377,14 +377,11 @@ export const updateEluWorkerUsage = <
   )
   if (eluTaskStatisticsRequirements?.aggregate === true) {
     if (message.taskPerformance?.elu != null) {
-      if (workerUsage.elu.utilization != null) {
-        workerUsage.elu.utilization =
-          (workerUsage.elu.utilization +
-            message.taskPerformance.elu.utilization) /
-          2
-      } else {
-        workerUsage.elu.utilization = message.taskPerformance.elu.utilization
-      }
+      workerUsage.elu.count = (workerUsage.elu.count ?? 0) + 1
+      workerUsage.elu.utilization =
+        ((workerUsage.elu.utilization ?? 0) * (workerUsage.elu.count - 1) +
+          message.taskPerformance.elu.utilization) /
+        workerUsage.elu.count
     }
   }
 }
diff --git a/src/pools/worker.ts b/src/pools/worker.ts
index edc659d37..63c508d08 100644
--- a/src/pools/worker.ts
+++ b/src/pools/worker.ts
@@ -59,6 +59,7 @@ export const MeasurementHistorySize = 386
  */
 export interface EventLoopUtilizationMeasurementStatistics {
   readonly active: MeasurementStatistics
+  count?: number
   readonly idle: MeasurementStatistics
   utilization?: number
 }
-- 
2.43.0