ufff... now that I look at the Class::DBI::Cachable and Class::DBI::ObjectCache it seems a little bit more weird than I expected...
It seems that it caches only the ->retrieve() call, but not retrieve_all().
On the other hand the cache has to be build on the Application level, but later reused on Session and/or Page level.
Probably wiser solution will be to put some Application code to build HASH on server startup so it stays in memory (for the configuration data).