restore: disable pd follower handle (#60116)

close #60105

Author: 3pointer

br/pkg/conn/BUILD.bazel

@@ -18,8 +18,6 @@ go_library(
         "//pkg/ddl",
         "//pkg/domain",
         "//pkg/kv",
-        "//pkg/sessionctx/vardef",
-        "//pkg/sessionctx/variable",
         "@com_github_docker_go_units//:go-units",
         "@com_github_opentracing_opentracing_go//:opentracing-go",
         "@com_github_pingcap_errors//:errors",

br/pkg/conn/conn.go

@@ -32,8 +32,6 @@ import (
 	"github.com/pingcap/tidb/pkg/ddl"
 	"github.com/pingcap/tidb/pkg/domain"
 	"github.com/pingcap/tidb/pkg/kv"
-	"github.com/pingcap/tidb/pkg/sessionctx/vardef"
-	"github.com/pingcap/tidb/pkg/sessionctx/variable"
 	"github.com/tikv/client-go/v2/oracle"
 	"github.com/tikv/client-go/v2/tikv"
 	"github.com/tikv/client-go/v2/txnkv/txnlock"
@@ -231,16 +229,6 @@ func NewMgr(
 		}
 	}
 
-	if err = g.UseOneShotSession(storage, !needDomain, func(se glue.Session) error {
-		enableFollowerHandleRegion, err := se.GetGlobalSysVar(vardef.PDEnableFollowerHandleRegion)
-		if err != nil {
-			return err
-		}
-		return controller.SetFollowerHandle(variable.TiDBOptOn(enableFollowerHandleRegion))
-	}); err != nil {
-		return nil, errors.Trace(err)
-	}
-
 	mgr := &Mgr{
 		PdController: controller,
 		storage:      storage,

br/pkg/task/restore.go

@@ -836,9 +836,14 @@ func RunRestore(c context.Context, g glue.Glue, cmdName string, cfg *RestoreConf
 			if err != nil {
 				log.Warn("failed to remove checkpoint data for compacted restore", zap.Error(err))
 			}
-			err = cfg.snapshotCheckpointMetaManager.RemoveCheckpointData(c)
-			if err != nil {
-				log.Warn("failed to remove checkpoint data for snapshot restore", zap.Error(err))
+			// Skip removing snapshot checkpoint data if this is a pure log restore
+			// (i.e. restoring only from log backup without a base snapshot backup),
+			// since snapshotCheckpointMetaManager would be nil in that case
+			if cfg.snapshotCheckpointMetaManager != nil {
+				err = cfg.snapshotCheckpointMetaManager.RemoveCheckpointData(c)
+				if err != nil {
+					log.Warn("failed to remove checkpoint data for snapshot restore", zap.Error(err))
+				}
 			}
 		} else {
 			err = cfg.snapshotCheckpointMetaManager.RemoveCheckpointData(c)

br/tests/br_full_ddl/run.sh

@@ -136,10 +136,10 @@ fi
 
 # when we have backup stats during backup, we cannot close domain during one shot session.
 # so we can check the log count of `one shot domain closed`.
-# we will call UseOneShotSession twice to get the value global variable.
+# we will call UseOneShotSession once to get the value global variable.
 one_shot_session_count=$(cat $LOG | grep "one shot session closed" | wc -l | xargs)
 one_shot_domain_count=$(cat $LOG | grep "one shot domain closed" | wc -l | xargs)
-if [ "${one_shot_session_count}" -ne "2" ] || [ "$one_shot_domain_count" -ne "0" ];then
+if [ "${one_shot_session_count}" -ne "1" ] || [ "$one_shot_domain_count" -ne "0" ];then
     echo "TEST: [$TEST_NAME] fail on one shot session check, $one_shot_session_count, $one_shot_domain_count"
     exit 1
 fi

br/tests/br_incremental_ddl/run.sh

@@ -41,10 +41,10 @@ run_br --pd $PD_ADDR backup table -s "local://$TEST_DIR/$DB/full" --db $DB -t $T
 
 # when we backup, we should close domain in one shot session.
 # so we can check the log count of `one shot domain closed` to be 2.
-# we will call UseOneShotSession twice to get the value global variable.
+# we will call UseOneShotSession once to get the value global variable.
 one_shot_session_count=$(cat $LOG | grep "one shot session closed" | wc -l | xargs)
 one_shot_domain_count=$(cat $LOG | grep "one shot domain closed" | wc -l | xargs)
-if [ "${one_shot_session_count}" -ne "2" ] || [ "$one_shot_domain_count" -ne "2" ];then
+if [ "${one_shot_session_count}" -ne "1" ] || [ "$one_shot_domain_count" -ne "1" ];then
     echo "TEST: [$TEST_NAME] fail on one shot session check during backup, $one_shot_session_count, $one_shot_domain_count"
     exit 1
 fi
@@ -74,13 +74,13 @@ last_backup_ts=$(run_br validate decode --field="end-version" -s "local://$TEST_
 run_br --pd $PD_ADDR backup db -s "local://$TEST_DIR/$DB/inc" --db $DB --lastbackupts $last_backup_ts --log-file $LOG
 
 # when we doing incremental backup, we should close domain in one shot session.
-# so we can check the log count of `one shot domain closed` to be 3.
-# we will call UseOneShotSession three times
-# 1. to get the value global variable twice.
+# so we can check the log count of `one shot domain closed` to be 2.
+# we will call UseOneShotSession two times
+# 1. to get the value global variable once.
 # 2. to get all ddl jobs with session.
 one_shot_session_count=$(cat $LOG | grep "one shot session closed" | wc -l | xargs)
 one_shot_domain_count=$(cat $LOG | grep "one shot domain closed" | wc -l | xargs)
-if [ "${one_shot_session_count}" -ne "3" ] || [ "$one_shot_domain_count" -ne "3" ];then
+if [ "${one_shot_session_count}" -ne "2" ] || [ "$one_shot_domain_count" -ne "2" ];then
     echo "TEST: [$TEST_NAME] fail on one shot session check during inc backup, $one_shot_session_count, $one_shot_domain_count"
     exit 1
 fi