Questions specifically regarding Virtuoso are generally best raised on the public OpenLink Discussion Forums, the Virtuoso Users mailing list, or through a confidential Support Case.
That said, regarding your specific questions -- the server-side timeout setting trumps that requested by any query -- i.e., the query setting only has effect when it's shorter than that set on the server. You can adjust the server-side setting (MaxQueryExecutionTime
), among many other things, on your own instance.
DBpedia-specific questions, discussion, submissions, etc., are usually best directed to the DBpedia discussion list. The public DBpedia endpoint does indeed have various usage limitations, which are part of what make it viable as a generously provided public service.