diff --git a/internal/querynode/data_sync_service.go b/internal/querynode/data_sync_service.go
index a52c5b89b269086951b2066dc667e986dbcd3f2b..8ef041d690baf073505731ea09bef7c83a7d6753 100644
--- a/internal/querynode/data_sync_service.go
+++ b/internal/querynode/data_sync_service.go
@@ -263,6 +263,7 @@ func (dsService *dataSyncService) startPartitionFlowGraph(partitionID UniqueID,
 	return nil
 }
 
+// removePartitionFlowGraph removes the partition flow graph from dataSyncService by partitionID
 func (dsService *dataSyncService) removePartitionFlowGraph(partitionID UniqueID) {
 	dsService.mu.Lock()
 	defer dsService.mu.Unlock()