How to increase PROCESSES initialization parameter. ORA-00020 maximum number of processes exceeded..

ORA-00020 maximum number of processes exceeded

Cause: All process state objects are in use.

Action: Increase the value of the PROCESSES initialization parameter.

ORA-00020 comes under "Oracle Database Server Messages". These messages are generated by the Oracle database server when running any Oracle program.

Reference: Oracle Documentation

How to increase PROCESSES initialization parameter:

1.   Login as sysdba

   sqlplus / as sysdba

2. Check Current Setting of Parameters

   sql> show parameter sessions;

   sql> show parameter processes;

   sql> show parameter transactions;

3.   If you are planning to increase "PROCESSES" parameter you should also plan to increase "sessions and "transactions" parameters

   A basic formula for determining these parameter values is as follows:

      processes=x

      sessions=x*1.1+5

      transactions=sessions*1.1

4.   These paramters can't be modified in memory. You have to modify the spfile only (scope=spfile) and bounce the instance.

   sql> alter system set processes=500 scope=spfile;

   sql> alter system set sessions=555 scope=spfile;

   sql> alter system set transactions=610 scope=spfile;

   sql> shutdown abort

   sql> startup