Calculation Method Of Database Session, Processes, Transaction.

processes=x
sessions=x*1.1+5
transactions=sessions*1.1

E.g.
processes=500
sessions=555
transactions=610

sql> alter system set processes=500 scope=both sid='*';
sql> alter system set sessions=555 scope=both sid='*';
sql> alter system set transactions=610 scope=both sid='*';