WAL condensation can be triggered manually by issuing the following statement:

A backup copy of the main.wal file is stored in the main_wal_backups subdirectory, and then the main.wal file is compacted by dropping unused information.

The files stored in the pdts directory are not affected by the condensation. They are cleaned (removed) automatically when the PDT data stored inside is no longer needed, for example, after update propagation.