coprocessor: skip empty tidb nodes

br/cmd/br/backup.go

@@ -46,8 +46,13 @@ func runBackupCommand(command *cobra.Command, cmdName string) error {
 		return nil
 	}
 
-	// No need to cache the coproceesor result
-	config.GetGlobalConfig().TiKVClient.CoprCache.CapacityMB = 0
+	config.UpdateGlobal(func(conf *config.Config) {
+		// Need to be skipped when the cluster has TiDB type coprocessor tasks
+		conf.AdvertiseAddress = config.UnavailableIP
+
+		// No need to cache the coproceesor result
+		conf.TiKVClient.CoprCache.CapacityMB = 0
+	})
 
 	// Disable the memory limit tuner. That's because the server memory is get from TiDB node instead of BR node.
 	gctuner.GlobalMemoryLimitTuner.DisableAdjustMemoryLimit()

br/cmd/br/restore.go

@@ -65,8 +65,13 @@ func runRestoreCommand(command *cobra.Command, cmdName string) error {
 		return nil
 	}
 
-	// No need to cache the coproceesor result
-	config.GetGlobalConfig().TiKVClient.CoprCache.CapacityMB = 0
+	config.UpdateGlobal(func(conf *config.Config) {
+		// Need to be skipped when the cluster has TiDB type coprocessor tasks
+		conf.AdvertiseAddress = config.UnavailableIP
+
+		// No need to cache the coproceesor result
+		conf.TiKVClient.CoprCache.CapacityMB = 0
+	})
 
 	// Disable the memory limit tuner. That's because the server memory is get from TiDB node instead of BR node.
 	gctuner.GlobalMemoryLimitTuner.DisableAdjustMemoryLimit()

pkg/config/config.go

@@ -100,6 +100,7 @@ const (
 	// MaxTokenLimit is the max token limit value.
 	MaxTokenLimit  = 1024 * 1024
 	DefSchemaLease = 45 * time.Second
+	UnavailableIP  = "<nil>"
 )
 
 // Valid config maps

pkg/executor/infoschema_cluster_table_test.go

@@ -208,6 +208,19 @@ func (s *mockStore) StartGCWorker() error         { panic("not implemented") }
 func (s *mockStore) Name() string                 { return "mockStore" }
 func (s *mockStore) Describe() string             { return "" }
 
+func TestSkipEmptyIPNodesForTiDBTypeCoprocessor(t *testing.T) {
+	originIP := config.GetGlobalConfig().AdvertiseAddress
+	config.GetGlobalConfig().AdvertiseAddress = config.UnavailableIP
+	defer func() { config.GetGlobalConfig().AdvertiseAddress = originIP }()
+	store, _ := testkit.CreateMockStoreAndDomain(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+	rows := tk.MustQuery("select * from information_schema.cluster_slow_query").Rows()
+	require.Equal(t, tk.Session().GetSessionVars().StmtCtx.WarningCount(), uint16(0))
+	// the TiDB node is skipped because it does not has IP
+	require.Equal(t, 0, len(rows))
+}
+
 func TestTiDBClusterInfo(t *testing.T) {
 	s := createInfosSchemaClusterTableSuite(t)
 

pkg/store/copr/coprocessor.go

@@ -589,6 +589,10 @@ func buildTiDBMemCopTasks(ranges *KeyRanges, req *kv.Request) ([]*copTask, error
 		if req.TiDBServerID > 0 && req.TiDBServerID != ser.ServerIDGetter() {
 			continue
 		}
+		// skip some nodes, such as BR created when backup/restore
+		if ser.IP == config.UnavailableIP {
+			continue
+		}
 
 		addr := net.JoinHostPort(ser.IP, strconv.FormatUint(uint64(ser.StatusPort), 10))
 		tasks = append(tasks, &copTask{