Is it currently possible to configure multi-KahaDB such that all offline durable subscriptions (for all destinations) go into one KahaDB instance while all other messages go into a second instance?
Durable subscription messages seem to break the assumption implicit in KahaDB's design decision to never compact data files, which is that as long as consumers are keeping up, all messages in a journal file will quickly become unneeded and the file can always be deleted in lieu of compacting it. And as has been discussed previously on this mailing list, it's possible for a single old data file to keep alive every data file after it if message-ack pairs span the data files, so a single durable subscription can theoretically prevent KahaDB from ever deleting another data file (which would be a bug, since correct operation of KahaDB is for data files to be deleted when they contain no unconsumed messages). Being able to push them into a separate KahaDB instance would make the assumption valid for the remaining messages in the store, but if that's not currently possible then one of the two features (mKahaDB for durable subscriptions, or compaction) needs to be implemented in 5.14.0. Tim
