diff --git a/internal/querynode/collection_replica.go b/internal/querynode/collection_replica.go
index c2f0d7f6454125de456da416ddec98c4ee5721a2..a7eec381fefcd0c93393849a16032225dca82a05 100644
--- a/internal/querynode/collection_replica.go
+++ b/internal/querynode/collection_replica.go
@@ -412,6 +412,7 @@ func (colReplica *collectionReplica) addSegmentPrivate(segmentID UniqueID, parti
 	return nil
 }
 
+// setSegment adds a segment to collectionReplica
 func (colReplica *collectionReplica) setSegment(segment *Segment) error {
 	colReplica.mu.Lock()
 	defer colReplica.mu.Unlock()