Using Oracle Enterprise Manager is the preferred method for monitoring Oracle RAC and Oracle Clusterware. Oracle Enterprise Manager is an Oracle Web-based integrated management solution for monitoring and administering your computing environment. From any location where you can access a web browser, you can manage Oracle RAC databases, application servers, host computers, and Web applications, in addition to related hardware and software. For example, you can monitor your Oracle RAC database performance from your office, home, or a remote site, if you have access to a Web browser.
View the overall system status, such as the number of nodes in the cluster and their current status. This high-level view capability means that you do not have to access each individual database instance for details if you just want to see inclusive, aggregated information.
View alert messages aggregated across all the instances with lists for the source of each alert message. An alert message is an indicator that signifies that a particular metric condition has been encountered. A metric is a unit of measurement used to report the system's conditions.
Review issues that are affecting the entire cluster and those issues that are affecting individual instances.
Monitor cluster cache coherency statistics to help you identify processing trends and optimize performance for your Oracle RAC environment. Cache coherency statistics measure how well the data in caches on multiple instances is synchronized. If the data caches are completely synchronized with each other, then reading a memory location from the cache on any instance will return the most recent data written to that location from any cache on any instance.
Oracle Enterprise Manager accumulates data over specified periods of time, called collection-based data. Oracle Enterprise Manager also provides current data, called real-time data.
Oracle Database 2 Day + Real Application Clusters Guide provides complete information about monitoring performance with Oracle Enterprise Manager, including: