Result cache in Real Application Clusters

The Oracle Database Real Application Cluster (RAC) option allows the sharing of a cluster database across multiple database instances. It enhances the scalability and availability of database applications.

The Result cache, being the native component of database instance memory, is supported on RAC environments. The behavior and handling of result caching on RAC is the same as that of a single instance database. Here are the salient features of result caching in RAC:

• Each RAC instance maintains a local version of the Server Result Cache in the shared pool of the SGA

• A result is added to the instance result cache when a user executes a SQL query or a PL/SQL function on a database instance

• If the same user executes the same query from another instance, the cached result is copied to that instance's result cache over RAC interconnect

• The dynamic view GV$RESULT_CACHE_OBJECTS will show duplicate entries with the same cache ID, but for different instances ...