[TAS] Fix empty hot swap replacement for slices (#6914)

* [TAS] Fix empty hot swap replacement for slices

* rm fg

Author: PBundyra

pkg/cache/scheduler/tas_flavor_snapshot.go

@@ -518,6 +518,9 @@ func (s *TASFlavorSnapshot) findReplacementAssignment(tr *TASPodSetRequests, exi
 	if reason != "" {
 		return nil, nil, reason
 	}
+	if replacementAssignment == nil || len(replacementAssignment[tr.PodSet.Name].Domains) == 0 {
+		return nil, nil, fmt.Sprintf("cannot find replacement assignment for unhealthy node: %v", wl.Status.UnhealthyNodes[0].Name)
+	}
 	newAssignment := s.mergeTopologyAssignments(replacementAssignment[tr.PodSet.Name], existingAssignment)
 	return newAssignment, replacementAssignment[tr.PodSet.Name], ""
 }

pkg/scheduler/scheduler_test.go

@@ -7023,6 +7023,52 @@ func TestScheduleForTAS(t *testing.T) {
 				utiltesting.MakeEventRecord("default", "foo", "Admitted", corev1.EventTypeNormal).Obj(),
 			},
 		},
+		"workload with unhealthyNode annotation; second pass; preferred; no fit when using slices; FailFast": {
+			nodes:           defaultNodes,
+			admissionChecks: []kueue.AdmissionCheck{defaultProvCheck},
+			topologies:      []kueue.Topology{defaultThreeLevelTopology},
+			resourceFlavors: []kueue.ResourceFlavor{defaultTASThreeLevelFlavor},
+			clusterQueues:   []kueue.ClusterQueue{defaultClusterQueue},
+			workloads: []kueue.Workload{
+				*utiltesting.MakeWorkload("foo", "default").
+					UnhealthyNodes("x0").
+					Queue("tas-main").
+					PodSets(*utiltesting.MakePodSet("one", 2).
+						PreferredTopologyRequest(tasBlockLabel).
+						SliceSizeTopologyRequest(2).
+						SliceRequiredTopologyRequest(tasRackLabel).
+						Request(corev1.ResourceCPU, "1").
+						Obj()).
+					ReserveQuota(
+						utiltesting.MakeAdmission("tas-main").
+							PodSets(utiltesting.MakePodSetAssignment("one").Count(2).
+								Assignment(corev1.ResourceCPU, "tas-default", "2000m").
+								TopologyAssignment(utiltesting.MakeTopologyAssignment(utiltas.Levels(&defaultSingleLevelTopology)).
+									Domain(utiltesting.MakeTopologyDomainAssignment([]string{"x0"}, 1).Obj()).
+									Domain(utiltesting.MakeTopologyDomainAssignment([]string{"x1"}, 1).Obj()).
+									Obj()).
+								Obj()).
+							Obj(),
+					).
+					Admitted(true).
+					Obj(),
+			},
+			wantNewAssignments: map[workload.Reference]kueue.Admission{
+				"default/foo": *utiltesting.MakeAdmission("tas-main").
+					PodSets(utiltesting.MakePodSetAssignment("one").Count(2).
+						Assignment(corev1.ResourceCPU, "tas-default", "2000m").
+						TopologyAssignment(utiltesting.MakeTopologyAssignment(utiltas.Levels(&defaultSingleLevelTopology)).
+							Domain(utiltesting.MakeTopologyDomainAssignment([]string{"x0"}, 1).Obj()).
+							Domain(utiltesting.MakeTopologyDomainAssignment([]string{"x1"}, 1).Obj()).
+							Obj()).
+						Obj()).
+					Obj(),
+			},
+			wantEvents: []utiltesting.EventRecord{
+				utiltesting.MakeEventRecord("default", "foo", "EvictedDueToNodeFailures", corev1.EventTypeNormal).
+					Message("Workload was evicted as there was no replacement for a failed node: x0").Obj(),
+			},
+		},
 	}
 	for name, tc := range cases {
 		t.Run(name, func(t *testing.T) {