Data Guard :: Difficulty In Detecting Archive Gap On Physical Standby

which of the following views on the physical standby will us correct information on synchronization with Primary database?

For example, when I checked v$archived_gap it did not return any rows but the max(applied_seq#) on v$archive_dest_status was lagging far behind from the max(sequence#) on Primary database

select max(applied_seq#) from v$archive_dest_status where dest_id=2;
select max(sequence#) from v$archived_log where applied='YES';
select * from v$archive_gap;