Overview of Service Administration

When you create and administer services, you are dividing the work that your database performs into manageable units. The goal of using services is to achieve optimal utilization of your database infrastructure. You can create and deploy services based on business requirements. Oracle Database can measure the performance for each service. Using the DBMS_MONITOR package, you can define both the application modules within a service and the individual actions for a module and monitor thresholds for these actions, enabling you to manage workloads to deliver capacity on demand.

When you create new services for your database, you should define the automatic workload management characteristics for each service, as described in "Service Characteristics".

In addition to creating services, you can:

• Delete a service. You can delete services that you created. However, you cannot delete or modify the properties of the default database service that Oracle Database created.

• Check the status of a service. A service can be assigned different roles among the available instances. In a complex database with many services, you may not remember the details of every service. Therefore, you may have to check the status on an instance or service basis. For example, you may have to know the status of a service for a particular instance before you make modifications to that instance or to the Oracle home from which it runs.

• Start or stop a service for a database or an instance. A service must be started before it can be used for client connections to that instance. If you shut down your database, for example, by running the SRVCTL command srvctl stop database -d db_unique_name where db_unique_name is the name of the database you want to stop, then Oracle Database stops all services for that database. Depending on the service management policy, you may have to manually restart the services when you start the database. Both the srvctl stop database and srvctl stop service commands accept the -force option to forcibly disconnect connections. To drain sessions for planned outages do not use the -force option.

  Note:

  If Oracle Database QoS Management is enabled for the Oracle RAC database, then the services are automatically restarted after they are stopped.

• Map a service to a consumer group. You can map services to Resource Manager Consumer groups to limit the amount of resources that services can use in an instance. You must create the consumer group and then map the service to the consumer group.

  See Also:

  Oracle Database PL/SQL Packages and Types Reference for information about the DBMS_RESOURCE_MANAGER.SET_CONSUMER_GROUP_MAPPING_PRI procedure

• Enable or disable a service for a database or an instance. By default, Oracle Clusterware attempts to restart a service automatically after failures. You can prevent this behavior by disabling a service. Disabling a service is useful when you must perform database or instance maintenance, such as when you are performing an upgrade and you want to prevent connection requests from succeeding.

• Relocate a service to a different instance. You can move a service from one instance to another instance to re-balance workloads, for example, after adding or deleting cluster nodes.