diff --git a/cdc/sinkv2/eventsink/cloudstorage/cloud_storage_dml_sink.go b/cdc/sinkv2/eventsink/cloudstorage/cloud_storage_dml_sink.go
index 081098b6ae9..e86ccf2a008 100644
--- a/cdc/sinkv2/eventsink/cloudstorage/cloud_storage_dml_sink.go
+++ b/cdc/sinkv2/eventsink/cloudstorage/cloud_storage_dml_sink.go
@@ -80,7 +80,7 @@ type dmlSink struct {
 	alive struct {
 		sync.RWMutex
 		// msgCh is a channel to hold eventFragment.
-		msgCh  chan eventFragment
+		msgCh  *chann.DrainableChann[eventFragment]
 		isDead bool
 	}
 
@@ -140,7 +140,7 @@ func NewCloudStorageSink(
 		cancel:          wgCancel,
 		dead:            make(chan struct{}),
 	}
-	s.alive.msgCh = make(chan eventFragment, defaultChannelSize)
+	s.alive.msgCh = chann.NewDrainableChann[eventFragment]()
 
 	encodedCh := make(chan eventFragment, defaultChannelSize)
 	workerChannels := make([]*chann.DrainableChann[eventFragment], cfg.WorkerCount)
@@ -148,7 +148,7 @@ func NewCloudStorageSink(
 	// create a group of encoding workers.
 	for i := 0; i < defaultEncodingConcurrency; i++ {
 		encoder := encoderBuilder.Build()
-		s.encodingWorkers[i] = newEncodingWorker(i, s.changefeedID, encoder, s.alive.msgCh, encodedCh)
+		s.encodingWorkers[i] = newEncodingWorker(i, s.changefeedID, encoder, s.alive.msgCh.Out(), encodedCh)
 	}
 	// create defragmenter.
 	s.defragmenter = newDefragmenter(encodedCh, workerChannels)
@@ -168,7 +168,7 @@ func NewCloudStorageSink(
 
 		s.alive.Lock()
 		s.alive.isDead = true
-		close(s.alive.msgCh)
+		s.alive.msgCh.CloseAndDrain()
 		s.alive.Unlock()
 		close(s.dead)
 
@@ -234,7 +234,7 @@ func (s *dmlSink) WriteEvents(txns ...*eventsink.CallbackableEvent[*model.Single
 
 		s.statistics.ObserveRows(txn.Event.Rows...)
 		// emit a TxnCallbackableEvent encoupled with a sequence number starting from one.
-		s.alive.msgCh <- eventFragment{
+		s.alive.msgCh.In() <- eventFragment{
 			seqNumber:      seq,
 			versionedTable: tbl,
 			event:          txn,
diff --git a/pkg/sink/cloudstorage/path.go b/pkg/sink/cloudstorage/path.go
index 448a6217dfc..ffed62d0d1f 100644
--- a/pkg/sink/cloudstorage/path.go
+++ b/pkg/sink/cloudstorage/path.go
@@ -192,27 +192,28 @@ func (f *FilePathGenerator) CheckOrWriteSchema(
 	_, checksum := mustParseSchemaName(tblSchemaFile)
 	schemaFileCnt := 0
 	lastVersion := uint64(0)
-	prefix := fmt.Sprintf(tableSchemaPrefix+"schema_", def.Schema, def.Table)
+	subDir := fmt.Sprintf(tableSchemaPrefix, def.Schema, def.Table)
 	checksumSuffix := fmt.Sprintf("%010d.json", checksum)
-	err = f.storage.WalkDir(ctx, &storage.WalkOption{ObjPrefix: prefix},
-		func(path string, _ int64) error {
-			schemaFileCnt++
-			if !strings.HasSuffix(path, checksumSuffix) {
-				return nil
-			}
-			version, parsedChecksum := mustParseSchemaName(path)
-			if parsedChecksum != checksum {
-				// TODO: parsedChecksum should be ignored, remove this panic
-				// after the new path protocol is verified.
-				log.Panic("invalid schema file name",
-					zap.String("path", path), zap.Any("checksum", checksum))
-			}
-			if version > lastVersion {
-				lastVersion = version
-			}
+	err = f.storage.WalkDir(ctx, &storage.WalkOption{
+		SubDir:    subDir, /* use subDir to prevent walk the whole storage */
+		ObjPrefix: subDir + "schema_",
+	}, func(path string, _ int64) error {
+		schemaFileCnt++
+		if !strings.HasSuffix(path, checksumSuffix) {
 			return nil
-		},
-	)
+		}
+		version, parsedChecksum := mustParseSchemaName(path)
+		if parsedChecksum != checksum {
+			// TODO: parsedChecksum should be ignored, remove this panic
+			// after the new path protocol is verified.
+			log.Panic("invalid schema file name",
+				zap.String("path", path), zap.Any("checksum", checksum))
+		}
+		if version > lastVersion {
+			lastVersion = version
+		}
+		return nil
+	})
 	if err != nil {
 		return err
 	}
diff --git a/pkg/sink/cloudstorage/path_test.go b/pkg/sink/cloudstorage/path_test.go
index 6a0dbe56c4a..ead5254fff4 100644
--- a/pkg/sink/cloudstorage/path_test.go
+++ b/pkg/sink/cloudstorage/path_test.go
@@ -17,9 +17,14 @@ import (
 	"context"
 	"fmt"
 	"net/url"
+	"os"
+	"path/filepath"
 	"testing"
 	"time"
 
+	timodel "github.com/pingcap/tidb/parser/model"
+	"github.com/pingcap/tidb/parser/mysql"
+	"github.com/pingcap/tidb/parser/types"
 	"github.com/pingcap/tiflow/cdc/model"
 	"github.com/pingcap/tiflow/engine/pkg/clock"
 	"github.com/pingcap/tiflow/pkg/config"
@@ -275,3 +280,51 @@ func TestIsSchemaFile(t *testing.T) {
 			"testCase: %s, path: %v", tt.name, tt.path)
 	}
 }
+
+func TestCheckOrWriteSchema(t *testing.T) {
+	t.Parallel()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	dir := t.TempDir()
+	f := testFilePathGenerator(ctx, t, dir)
+
+	var columns []*timodel.ColumnInfo
+	ft := types.NewFieldType(mysql.TypeLong)
+	ft.SetFlag(mysql.PriKeyFlag | mysql.NotNullFlag)
+	col := &timodel.ColumnInfo{
+		Name:         timodel.NewCIStr("Id"),
+		FieldType:    *ft,
+		DefaultValue: 10,
+	}
+	columns = append(columns, col)
+	tableInfo := &model.TableInfo{
+		TableInfo: &timodel.TableInfo{Columns: columns},
+		Version:   100,
+		TableName: model.TableName{
+			Schema:  "test",
+			Table:   "table1",
+			TableID: 20,
+		},
+	}
+
+	table := VersionedTableName{
+		TableNameWithPhysicTableID: tableInfo.TableName,
+		TableInfoVersion:           tableInfo.Version,
+	}
+
+	err := f.CheckOrWriteSchema(ctx, table, tableInfo)
+	require.NoError(t, err)
+	require.Equal(t, tableInfo.Version, f.versionMap[table])
+
+	// test only table version changed, schema file should be reused
+	table.TableInfoVersion = 101
+	err = f.CheckOrWriteSchema(ctx, table, tableInfo)
+	require.NoError(t, err)
+	require.Equal(t, tableInfo.Version, f.versionMap[table])
+
+	dir = filepath.Join(dir, "test/table1/meta")
+	cnt, err := os.ReadDir(dir)
+	require.NoError(t, err)
+	require.Equal(t, 1, len(cnt))
+}