The key features of Oracle Shared Server that make it an invaluable tool for Oracle DBAs include:
- Scalability: Oracle Shared Server can support a large number of concurrent users and sessions, making it ideal for high-volume applications.
- Efficiency: Oracle Shared Server uses resources more efficiently than dedicated servers, requiring fewer processes and less memory. This can lead to significant performance improvements, especially on systems with limited resources.
- Availability: Oracle Shared Server is more resilient to failures than dedicated servers. If a shared server process fails, the other shared server processes can continue to serve clients. This makes Oracle Shared Server a good choice for mission-critical applications.
- Manageability: Oracle Shared Server is easier to manage than dedicated servers. This is because there are fewer processes to monitor and manage.
In addition to these key features, Oracle Shared Server also offers a number of other benefits, such as:
- Improved performance for certain database features: Some database features, such as parallel execution and RAC, can perform better when using Oracle Shared Server.
- Reduced memory usage: Oracle Shared Server uses less memory than dedicated servers, because it shares a single PGA across all shared server processes.
- Reduced CPU usage: Oracle Shared Server can reduce CPU usage by offloading some tasks to the dispatcher process.
- Simplified configuration and management: Oracle Shared Server is easier to configure and manage than dedicated servers, because there are fewer processes to monitor and manage.
Overall, Oracle Shared Server is a powerful and versatile tool that can be used to improve the performance, scalability, availability, and manageability of Oracle databases. Here are some specific examples of how Oracle DBAs can use Oracle Shared Server to improve their database environments:
- Scalability: To improve the scalability of a database, Oracle DBAs can configure Oracle Shared Server to support a larger number of concurrent users and sessions. This can be done by increasing the number of shared server processes or by using dedicated servers for certain tasks, such as batch jobs.
- Efficiency: To improve the efficiency of a database, Oracle DBAs can tune the Oracle Shared Server configuration parameters. For example, they can adjust the number of shared server processes, the PGA size, and the dispatcher queue size.
- Availability: To improve the availability of a database, Oracle DBAs can configure Oracle Shared Server to be more resilient to failures. For example, they can use the dispatcher failover feature and the shared server failover feature.
- Manageability: To improve the manageability of a database, Oracle DBAs can use the Oracle Shared Server monitoring tools. For example, they can use the V$SESSION view to view information about shared server sessions and the V$SESS_TIME_MODEL view to view information about shared server timeouts.
Overall, Oracle Shared Server is a valuable tool for Oracle DBAs who want to improve the performance, scalability, availability, and manageability of their database environments.
This module demonstrated that the Shared Server can be used as a command-line utility to manage Oracle databases.
In addition, Oracle Shared Server's functionality is being merged into SQL*Plus, and that SQL*Plus now supercedes Server Manager as the command-line interface to Oracle. Some of the simpler Shared Server commands have been experimented with, and by now you are comfortable with starting Shared Server and connecting to a database.
You should also be comfortable entering and executing commands and know how to recover when you mistakenly enter an invalid command.