We have a number of databases which do not have any changes on weekends. With the test_decoding plugin, this results in the transaction logs growing very large (about 20GB per day) until the next change happens on Monday.
Currently I have been told this is because the connector will not be able to flush the WAL until it has at least one relevant change. The workaround is to perform dummy inserts with pg_cron or some other method.
It would be better if the WAL was able to be cleared every time a successful sync takes place, whether or not relevant changes have been detected.