diff --git a/internal/datacoord/segment_reference_manager.go b/internal/datacoord/segment_reference_manager.go
index 94eca4a3a1..8aa2a0ca38 100644
--- a/internal/datacoord/segment_reference_manager.go
+++ b/internal/datacoord/segment_reference_manager.go
@@ -109,7 +109,7 @@ func (srm *SegmentReferenceManager) AddSegmentsLock(taskID int64, segIDs []Uniqu
 	for _, segID := range segIDs {
 		srm.segmentReferCnt[segID]++
 	}
-	log.Info("add reference lock on segments successfully", zap.Int64s("segIDs", segIDs), zap.Int64("nodeID", nodeID))
+	log.Info("add reference lock on segments successfully", zap.Int64("taskID", taskID), zap.Int64s("segIDs", segIDs), zap.Int64("nodeID", nodeID))
 	return nil
 }
 
diff --git a/internal/datanode/flow_graph_delete_node.go b/internal/datanode/flow_graph_delete_node.go
index 316691e340..126ef19879 100644
--- a/internal/datanode/flow_graph_delete_node.go
+++ b/internal/datanode/flow_graph_delete_node.go
@@ -105,7 +105,7 @@ func (dn *deleteNode) Close() {
 	log.Info("Flowgraph Delete Node closing")
 }
 
-func (dn *deleteNode) bufferDeleteMsg(msg *msgstream.DeleteMsg, tr TimeRange) error {
+func (dn *deleteNode) bufferDeleteMsg(msg *msgstream.DeleteMsg, tr TimeRange) ([]UniqueID, error) {
 	log.Debug("bufferDeleteMsg", zap.Any("primary keys", msg.PrimaryKeys), zap.String("vChannelName", dn.channelName))
 
 	// Update delBuf for merged segments
@@ -129,11 +129,14 @@ func (dn *deleteNode) bufferDeleteMsg(msg *msgstream.DeleteMsg, tr TimeRange) er
 	primaryKeys := storage.ParseIDs2PrimaryKeys(msg.PrimaryKeys)
 	segIDToPks, segIDToTss := dn.filterSegmentByPK(msg.PartitionID, primaryKeys, msg.Timestamps)
 
+	segIDs := make([]UniqueID, 0, len(segIDToPks))
 	for segID, pks := range segIDToPks {
+		segIDs = append(segIDs, segID)
+
 		rows := len(pks)
 		tss, ok := segIDToTss[segID]
 		if !ok || rows != len(tss) {
-			return fmt.Errorf("primary keys and timestamp's element num mis-match, segmentID = %d", segID)
+			return nil, fmt.Errorf("primary keys and timestamp's element num mis-match, segmentID = %d", segID)
 		}
 
 		var delDataBuf *DelDataBuf
@@ -164,23 +167,18 @@ func (dn *deleteNode) bufferDeleteMsg(msg *msgstream.DeleteMsg, tr TimeRange) er
 		dn.delBuf.Store(segID, delDataBuf)
 	}
 
-	return nil
+	return segIDs, nil
 }
 
-func (dn *deleteNode) showDelBuf() {
-	segments := dn.replica.filterSegments(dn.channelName, common.InvalidPartitionID)
-	for _, seg := range segments {
-		segID := seg.segmentID
+func (dn *deleteNode) showDelBuf(segIDs []UniqueID, ts Timestamp) {
+	for _, segID := range segIDs {
 		if v, ok := dn.delBuf.Load(segID); ok {
 			delDataBuf, _ := v.(*DelDataBuf)
 			log.Debug("delta buffer status",
+				zap.Uint64("timestamp", ts),
 				zap.Int64("segment ID", segID),
 				zap.Int64("entries", delDataBuf.GetEntriesNum()),
 				zap.String("vChannel", dn.channelName))
-		} else {
-			log.Debug("segment not exist",
-				zap.Int64("segment ID", segID),
-				zap.String("vChannel", dn.channelName))
 		}
 	}
 }
@@ -211,22 +209,24 @@ func (dn *deleteNode) Operate(in []Msg) []Msg {
 		msg.SetTraceCtx(ctx)
 	}
 
+	var segIDs []UniqueID
 	for i, msg := range fgMsg.deleteMessages {
 		traceID, _, _ := trace.InfoFromSpan(spans[i])
 		log.Info("Buffer delete request in DataNode", zap.String("traceID", traceID))
 
-		err := dn.bufferDeleteMsg(msg, fgMsg.timeRange)
+		tmpSegIDs, err := dn.bufferDeleteMsg(msg, fgMsg.timeRange)
 		if err != nil {
 			// error occurs only when deleteMsg is misaligned, should not happen
 			err = fmt.Errorf("buffer delete msg failed, err = %s", err)
 			log.Error(err.Error())
 			panic(err)
 		}
+		segIDs = append(segIDs, tmpSegIDs...)
 	}
 
-	// show all data in dn.delBuf
+	// show changed segment's status in dn.delBuf of a certain ts
 	if len(fgMsg.deleteMessages) != 0 {
-		dn.showDelBuf()
+		dn.showDelBuf(segIDs, fgMsg.timeRange.timestampMax)
 	}
 
 	// handle flush
diff --git a/internal/datanode/flow_graph_delete_node_test.go b/internal/datanode/flow_graph_delete_node_test.go
index b16055ced9..9eda476f27 100644
--- a/internal/datanode/flow_graph_delete_node_test.go
+++ b/internal/datanode/flow_graph_delete_node_test.go
@@ -31,6 +31,7 @@ import (
 	"github.com/milvus-io/milvus/internal/storage"
 	"github.com/milvus-io/milvus/internal/util/flowgraph"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 var deleteNodeTestDir = "/tmp/milvus_test/deleteNode"
@@ -426,3 +427,44 @@ func TestFlowGraphDeleteNode_Operate(t *testing.T) {
 		})
 	})
 }
+
+func TestFlowGraphDeleteNode_showDelBuf(t *testing.T) {
+	cm := storage.NewLocalChunkManager(storage.RootPath(deleteNodeTestDir))
+	defer cm.RemoveWithPrefix("")
+
+	fm := NewRendezvousFlushManager(NewAllocatorFactory(), cm, &mockReplica{}, func(*segmentFlushPack) {}, emptyFlushAndDropFunc)
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+	defer cancel()
+
+	chanName := "datanode-test-FlowGraphDeletenode-showDelBuf"
+	testPath := "/test/datanode/root/meta"
+	assert.NoError(t, clearEtcd(testPath))
+	Params.EtcdCfg.MetaRootPath = testPath
+	Params.DataNodeCfg.DeleteBinlogRootPath = testPath
+
+	c := &nodeConfig{
+		replica:      &mockReplica{},
+		allocator:    NewAllocatorFactory(),
+		vChannelName: chanName,
+	}
+	delNode, err := newDeleteNode(ctx, fm, make(chan string, 1), c)
+	require.NoError(t, err)
+
+	tests := []struct {
+		seg     UniqueID
+		numRows int64
+	}{
+		{111, 10},
+		{112, 10},
+		{113, 1},
+	}
+
+	for _, test := range tests {
+		delBuf := newDelDataBuf()
+		delBuf.updateSize(test.numRows)
+		delNode.delBuf.Store(test.seg, delBuf)
+	}
+
+	delNode.showDelBuf([]UniqueID{111, 112, 113}, 100)
+}