Session Management - Oracle 10g/11g Data and Database Management Utilities - page 183

SQL> ALTER SYSTEM
2 SET RESOURCE_MANAGER_PLAN = ActivatedPlan;
The activated plan indicates the plan that rules the current instance:
The DBMS_RESOURCE_MANAGER package can be used too to achieve the same result.
SQL> begin
2 DBMS_RESOURCE_MANAGER.SWITCH_PLAN ('ActivatedPlan');
3 end;
4 /
You can use the DBMS_SCHEDULER package to perform plan activation at specific
points in time, this is useful to allow a daily plan to be active during working hours
and a maintenance plan active during off hours.
Testing and monitoring
Two tests are performed to show the different emphasis achieved once Resource
Manager does its work. During the first scenario the SCOTT user is connected
through two different services, the sales and the datawarehouse services. The active
plan was originally OLTP , which simulates an environment where the users that
entered the database through the datawarehouse service are relegated to a lower
CPU priority. On the second scenario the plan is switched to an off hours plan, in this
plan the directives the users that entered the database through the datawarehouse
service automatically have a higher CPU priority.
Three sessions are open, each session gets access through a different service, thus
the resource allocated for each connection are different and the CPU emphasis
each session will experiment will depend on the currently active plan. Each session
performs the same workload starting at the same time so they compete for the same
resources within the same time frame.