The main reason for such situation is the fact the Zabbix server keeps persistent connections to a database - in such case DRCP would be a source of problems rather than a helper. Thus only the GUI part may be a subject to such configuration. Furthermore in future versions of Zabbix the database logic is planned to be located in the API, which in turn will be a part of the Zabbix server as well (while the GUI will call the API), and with such architecture the DRCP will be no longer an option.
Anyway this is still interesting feature assuming one makes an extensive use of the GUI, while on version below 3.X
-- this call creates a pool on a database side - first argument will -- become a pool name in the future (currently there is only 1 pool) begin dbms_connection_pool.configure_pool( null, minsize=5, maxsize=20, inactivity_timeout=>300, max_think_time=>600); end; / -- this call starts the pool exec dbms_connection_pool.start_pool(); -- this call stops the pool exec dbms_connection_pool.stop_pool(); -- calls like the one below allows pool parameters change begin dbms_connection_pool.ALTER_PARAM( null, param_name=>'session_cached_cursors', param_value=>'50'); end; /