[cluster agent][autoscaling] fix target hash check (#44910)

celenechang · web-flow · commit 1b40b8cea676 · 2026-01-09T15:33:04.000Z
### What does this PR do?

Fixes behavior if a target NodePool is not found in the cluster for an inferred NodePool

### Motivation

Fix unintended behavior when patching nodepools

### Describe how you validated your changes

In a test cluster pointing to staging, made sure inferred NodePools could be patched properly

### Additional Notes


Co-authored-by: celene &lt;celene@datadoghq.com&gt;
diff --git a/pkg/clusteragent/autoscaling/cluster/controller.go b/pkg/clusteragent/autoscaling/cluster/controller.go
@@ -153,12 +153,12 @@ func (c *Controller) syncNodePool(ctx context.Context, name string, nodePool *ka
 				log.Errorf("Error converting Target NodePool: %v", err)
 				return autoscaling.Requeue
 			}
-		}
 
-		// Only create or update if there is no TargetHash (i.e. it is fully Datadog-managed), or if the TargetHash has not changed
-		if !checkTargetHash(npi, targetNp) {
-			log.Infof("NodePool: %s TargetHash (%s) has changed since recommendation was generated; no action will be applied.", npi.Name(), npi.TargetHash())
-			return autoscaling.NoRequeue
+			// Only create or update if the TargetHash has not changed
+			if npi.TargetHash() != targetNp.GetAnnotations()[model.KarpenterNodePoolHashAnnotationKey] {
+				log.Infof("NodePool: %s TargetHash (%s) has changed since recommendation was generated; no action will be applied.", npi.Name(), npi.TargetHash())
+				return autoscaling.NoRequeue
+			}
 		}
 
 		if nodePool == nil {
@@ -190,13 +190,6 @@ func (c *Controller) syncNodePool(ctx context.Context, name string, nodePool *ka
 	return autoscaling.NoRequeue
 }
 
-func checkTargetHash(npi model.NodePoolInternal, targetNp *karpenterv1.NodePool) bool {
-	if targetNp == nil {
-		return false
-	}
-	return npi.TargetHash() == "" || npi.TargetHash() == targetNp.GetAnnotations()[model.KarpenterNodePoolHashAnnotationKey]
-}
-
 func (c *Controller) createNodePool(ctx context.Context, npi model.NodePoolInternal, knp *karpenterv1.NodePool) error {
 	log.Infof("Creating NodePool: %s", npi.Name())
 
diff --git a/releasenotes/notes/cluster-autoscaling-bugfix-0b0d0a56e9f01141.yaml b/releasenotes/notes/cluster-autoscaling-bugfix-0b0d0a56e9f01141.yaml
@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    Fix small bug in Cluster Autoscaling when checking Target Hash value.

-Original file line number
+Diff line change
@@ @@ -0,0 +1,4 @@ @@
 +---
 +fixes:
 +  - |
 +    Fix small bug in Cluster Autoscaling when checking Target Hash value.