diff --git a/internal/querynode/collection_replica.go b/internal/querynode/collection_replica.go
index 535fbe652d..c8b6aade6c 100644
--- a/internal/querynode/collection_replica.go
+++ b/internal/querynode/collection_replica.go
@@ -75,6 +75,7 @@ type ReplicaInterface interface {
 	getPartitionNum() int
 	// getSegmentIDs returns segment ids
 	getSegmentIDs(partitionID UniqueID) ([]UniqueID, error)
+	// getSegmentIDsByVChannel returns segment ids which virtual channel is vChannel
 	getSegmentIDsByVChannel(partitionID UniqueID, vChannel Channel) ([]UniqueID, error)
 
 	// segment