[YUNIKORN-3285] Child queue is not inheriting parent queue propertie…

pkg/scheduler/objects/queue.go

@@ -253,6 +253,22 @@ func (sq *Queue) getProperties() map[string]string {
 	return props
 }
 
+// GetProperties returns a copy of the properties for this queue.
+// Will never return nil; can return an empty map.
+func (sq *Queue) GetProperties() map[string]string {
+	return sq.getProperties()
+}
+
+// MergeProperties merges the parent queue properties with config properties into this queue.
+// Config properties override parent properties. This should be called after ApplyConf during
+// config reload to re-apply inherited properties from the parent.
+// Lock protected.
+func (sq *Queue) MergeProperties(parent, config map[string]string) {
+	sq.Lock()
+	defer sq.Unlock()
+	sq.mergeProperties(parent, config)
+}
+
 // mergeProperties merges the properties from the parent queue and the config in the set from new queue
 // lock free call
 func (sq *Queue) mergeProperties(parent, config map[string]string) {

pkg/scheduler/partition.go

@@ -241,6 +241,13 @@ func (pc *PartitionContext) updateQueues(config []configs.QueueConfig, parent *o
 			queue, err = objects.NewConfiguredQueue(queueConfig, parent, false, pc.appQueueMapping)
 		} else {
 			oldMax, err = queue.ApplyConf(queueConfig)
+			if err == nil {
+				// Re-apply inherited properties from parent, mirroring the NewConfiguredQueue path.
+				// ApplyConf sets sq.properties to only the queue's own config properties, which
+				// drops any previously inherited values and prevents parent property changes from
+				// propagating to existing child queues on config reload.
+				queue.MergeProperties(parent.GetProperties(), queueConfig.Properties)
+			}
 		}
 		if err != nil {
 			return err

pkg/scheduler/partition_test.go

@@ -1428,6 +1428,66 @@ func TestUpdateQueues(t *testing.T) {
 	assertUpdateQueues(t, "both", map[string]string{})
 }
 
+// TestUpdateQueuesInheritedProperties verifies that a child queue inherits
+// properties from its parent on config reload (updateQueues path).
+func TestUpdateQueuesInheritedProperties(t *testing.T) {
+	const customProp = "custom.test.property"
+
+	initialConf := []configs.QueueConfig{
+		{
+			Name:   "parent",
+			Parent: true,
+			Properties: map[string]string{
+				customProp: "value1",
+			},
+			Queues: []configs.QueueConfig{
+				{
+					Name:   "leaf",
+					Parent: false,
+				},
+			},
+		},
+	}
+
+	partition, err := newBasePartition()
+	assert.NilError(t, err, "partition create failed")
+	root := partition.GetQueue("root")
+	assert.Assert(t, root != nil, "root queue not found")
+
+	// initial load: leaf should inherit the property from parent
+	err = partition.updateQueues(initialConf, root)
+	assert.NilError(t, err, "initial updateQueues failed")
+
+	leaf := partition.GetQueue("root.parent.leaf")
+	assert.Assert(t, leaf != nil, "leaf queue should exist")
+	assert.Equal(t, leaf.GetProperties()[customProp], "value1",
+		"leaf should inherit property from parent on initial load")
+
+	// config reload: parent changes property value; leaf should pick up the new value
+	updatedConf := []configs.QueueConfig{
+		{
+			Name:   "parent",
+			Parent: true,
+			Properties: map[string]string{
+				customProp: "value2",
+			},
+			Queues: []configs.QueueConfig{
+				{
+					Name:   "leaf",
+					Parent: false,
+				},
+			},
+		},
+	}
+	err = partition.updateQueues(updatedConf, root)
+	assert.NilError(t, err, "config-reload updateQueues failed")
+
+	leaf = partition.GetQueue("root.parent.leaf")
+	assert.Assert(t, leaf != nil, "leaf queue should still exist after reload")
+	assert.Equal(t, leaf.GetProperties()[customProp], "value2",
+		"leaf should inherit updated property from parent on config reload")
+}
+
 func TestReAddQueues(t *testing.T) {
 	conf := []configs.QueueConfig{
 		{