We just migrated to TD 15.10 . What am observing is , pseudo table locking is no longer appearing in explain plan, rather its shows, First, we lock tablename for write on a reserved RowHash to prevent global deadlock. Seems like this is new in TD 15, so what is this reserved rowhash technique , is it similar to pseudo table locking concept.
Are you sure it's TD15, not 15.10?
This is a side effect of Partition-Level-Locking introduced in TD15.10, you get good ol' we lock a distinct DBC."pseudo table" only in DDL-statements, in DML it's always a so-called Proxy Lock now.
This is documented in the SQL Request and Transaction Processing manual.