Fix unnecessary HPA updates

Signed-off-by: Zbynek Roubalik <zroubali@redhat.com>

controllers/hpa.go

@@ -3,6 +3,7 @@ package controllers
 import (
  "context"
  "fmt"
+ "sort"
 
  "github.com/go-logr/logr"
  version "github.com/kedacore/keda/v2/version"
@@ -161,6 +162,12 @@ func (r *ScaledObjectReconciler) getScaledObjectMetricSpecs(logger logr.Logger,
  scaler.Close()
  }
 
+ // sort metrics in ScaledObject, this way we always check the same resource in Reconcile loop and we can prevent unnecessary HPA updates,
+ // see https://github.com/kedacore/keda/issues/1531 for details
+ sort.Slice(scaledObjectMetricSpecs, func(i, j int) bool {
+ return scaledObjectMetricSpecs[i].Type < scaledObjectMetricSpecs[j].Type
+ })
+
  // store External.MetricNames,Resource.MetricsNames used by scalers defined in the ScaledObject
  status := scaledObject.Status.DeepCopy()
  status.ExternalMetricNames = externalMetricNames