Getting over max processes exceeded error

Sometimes due to the default setting or limit on process, the server might hang up. To get over this problem, increase the number of processes to a more appropriate value.
login as sys in SQL Plus and type the following code

-- this will give you the list of all the processes along with their numbers
SQL> show parameter processes
-- this will give you the current setting for the number of processes
SQL> select count(*) from v$process;
-- change it to something higher
SQL> alter system set processes=100 scope=spfile; 

Don't forget to shutdown the database and restart it.

Similarly we can change the job queue processes too

SQL> show parameter job_queue_process 
SQL> ALTER SYSTEM SET job_queue_processes=20;