There are JFR events for the Placeholders table, LoaderConstraintTable and ProtectionDomainCacheTable. These events expose implementation details for these tables that we'd rather not expose. A users visibility into these tables will not be helpful and it restricts our ability to make these a different (smaller) table or in the case of ProtectionDomain, not a table at all.

The Dictionary table (table of loaded classes) is useful from a users' perspective because it can be resized and we wanted to have events for the resizing. These other tables came along in that change.