nomad: remove NodesByDatacenterStatus

nomad/state/schema.go

@@ -69,28 +69,6 @@ func nodeTableSchema() *memdb.TableSchema {
 					Lowercase: true,
 				},
 			},
-
-			// DC status is a compound index on both the
-			// datacenter and the node status. This allows
-			// us to filter to a set of eligible nodes more
-			// quickly for selection.
-			"dc-status": &memdb.IndexSchema{
-				Name:         "dc-status",
-				AllowMissing: false,
-				Unique:       false,
-				Indexer: &memdb.CompoundIndex{
-					AllowMissing: false,
-					Indexes: []memdb.Indexer{
-						&memdb.StringFieldIndex{
-							Field:     "Datacenter",
-							Lowercase: true,
-						},
-						&memdb.StringFieldIndex{
-							Field: "Status",
-						},
-					},
-				},
-			},
 		},
 	}
 }

nomad/state/state_store.go

@@ -207,18 +207,6 @@ func (s *StateStore) Nodes() (memdb.ResultIterator, error) {
 	return iter, nil
 }
 
-// Nodes returns an iterator over all the nodes in a DC with a given status
-func (s *StateStore) NodesByDatacenterStatus(dc, status string) (memdb.ResultIterator, error) {
-	txn := s.db.Txn(false)
-
-	// Walk the nodes table, filtering on DC and Status
-	iter, err := txn.Get("nodes", "dc-status", dc, status)
-	if err != nil {
-		return nil, err
-	}
-	return iter, nil
-}
-
 // RegisterJob is used to register a job or update a job definition
 func (s *StateStore) RegisterJob(index uint64, job *structs.Job) error {
 	txn := s.db.Txn(true)

nomad/state/state_store_test.go

@@ -151,69 +151,6 @@ func TestStateStore_Nodes(t *testing.T) {
 	}
 }
 
-func TestStateStore_NodesByDatacenterStatus(t *testing.T) {
-	state := testStateStore(t)
-	var dc1 []*structs.Node
-	var dc2 []*structs.Node
-
-	for i := 0; i < 10; i++ {
-		node := mock.Node()
-		if i%2 == 0 {
-			node.Datacenter = "dc2"
-			dc2 = append(dc2, node)
-		} else {
-			dc1 = append(dc1, node)
-		}
-
-		err := state.RegisterNode(1000+uint64(i), node)
-		if err != nil {
-			t.Fatalf("err: %v", err)
-		}
-	}
-
-	iter, err := state.NodesByDatacenterStatus("dc1", structs.NodeStatusReady)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	var out []*structs.Node
-	for {
-		raw := iter.Next()
-		if raw == nil {
-			break
-		}
-		out = append(out, raw.(*structs.Node))
-	}
-
-	sort.Sort(NodeIDSort(dc1))
-	sort.Sort(NodeIDSort(out))
-
-	if !reflect.DeepEqual(dc1, out) {
-		t.Fatalf("bad: %#v %#v", dc1, out)
-	}
-
-	iter, err = state.NodesByDatacenterStatus("dc2", structs.NodeStatusReady)
-	if err != nil {
-		t.Fatalf("err: %v", err)
-	}
-
-	out = out[:0]
-	for {
-		raw := iter.Next()
-		if raw == nil {
-			break
-		}
-		out = append(out, raw.(*structs.Node))
-	}
-
-	sort.Sort(NodeIDSort(dc2))
-	sort.Sort(NodeIDSort(out))
-
-	if !reflect.DeepEqual(dc2, out) {
-		t.Fatalf("bad: %#v %#v", dc2, out)
-	}
-}
-
 func TestStateStore_RestoreNode(t *testing.T) {
 	state := testStateStore(t)
 

scheduler/scheduler.go

@@ -56,9 +56,6 @@ type State interface {
 	// The type of each result is *structs.Node
 	Nodes() (memdb.ResultIterator, error)
 
-	// Nodes returns an iterator over all the nodes in a DC with a given status
-	NodesByDatacenterStatus(dc, status string) (memdb.ResultIterator, error)
-
 	// AllocsByJob returns the allocations by JobID
 	AllocsByJob(jobID string) ([]*structs.Allocation, error)
 

scheduler/util.go

@@ -117,19 +117,33 @@ func diffAllocs(job *structs.Job, taintedNodes map[string]bool,
 
 // readyNodesInDCs returns all the ready nodes in the given datacenters
 func readyNodesInDCs(state State, dcs []string) ([]*structs.Node, error) {
-	var out []*structs.Node
+	// Index the DCs
+	dcMap := make(map[string]struct{}, len(dcs))
 	for _, dc := range dcs {
-		iter, err := state.NodesByDatacenterStatus(dc, structs.NodeStatusReady)
-		if err != nil {
-			return nil, err
+		dcMap[dc] = struct{}{}
+	}
+
+	// Scan the nodes
+	var out []*structs.Node
+	iter, err := state.Nodes()
+	if err != nil {
+		return nil, err
+	}
+	for {
+		raw := iter.Next()
+		if raw == nil {
+			break
 		}
-		for {
-			raw := iter.Next()
-			if raw == nil {
-				break
-			}
-			out = append(out, raw.(*structs.Node))
+
+		// Filter on datacenter and status
+		node := raw.(*structs.Node)
+		if node.Status != structs.NodeStatusReady {
+			continue
 		}
+		if _, ok := dcMap[node.Datacenter]; !ok {
+			continue
+		}
+		out = append(out, node)
 	}
 	return out, nil
 }