SQL Server, Plan Cache Object
The Plan Cacheobject provides counters to monitor how SQL Server uses memory to store objects such as stored procedures, ad hoc and prepared Transact-SQL statements, and triggers. Multiple instances of the Plan Cache object can be monitored at the same time, with each instance representing a different type of plan to monitor.
This table describes are the SQLServer:Plan Cachecounters.
SQL Server Plan Cache counters
Cache Hit Ratio
Ratio between cache hits and lookups.
Cache Object Counts
Number of cache objects in the cache.
Number of 8-kilobyte (KB) pages used by cache objects.
Cache Objects in use
Number of cache objects in use.
Each counter in the object contains the following instances:
Plan Cache instance
Information for all types of cache instances.
Query plans produced from an ad hoc Transact-SQL query, including auto-parameterized queries, or from Transact-SQL statements prepared using sp_prepare or sp_cursorprepare. SQL Server caches the plans for ad hoc Transact-SQL statements for later reuse if the identical Transact-SQL statement is later executed. User-parameterized queries (even if not explicitly prepared) are also monitored as Prepared SQL Plans.
Query plans generated by creating a stored procedure, function, or trigger.
Normalized trees for views, rules, computed columns, and check constraints.
Extended Stored Procedures
Catalog information for extended stores procedures.
Temporary Tables & Table Variables
Cache information related to temporary tables and table variables.
For more information about caching query plans, see Execution Plan Caching and Reuse.