To increase DB process

You might also want to check if the number of connections reaches the database's PROCESSES parameter using following Unix command:

ps -ef | grep oracleSID | grep -v grep | wc -l

or

ps aux | grep oracleSID | grep -v grep | wc -l

If the value found is close to the value of the PROCESSES database parameter value, you might want to augment this value using following command:

alter system set processes=new value [scope=spfile];

A database bounce is required to let the new value become active.