SQL Server, Plan Cache object
Applies to: 
SQL Server
The Plan Cache object 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 | Description |
|---|---|
| Cache Hit Ratio | Ratio between cache hits and lookups. |
| Cache Hit Ratio Base | For internal use only. |
| Cache Object Counts | Number of cache objects in the cache. |
| Cache Objects in use | Number of cache objects in use. |
| Cache Pages | Number of 8-kilobyte (KB) pages used by cache objects. |
Each counter in the object contains the following instances:
| Plan Cache instance | Description |
|---|---|
| _Total | Information for all types of cache instances. |
| SQL Plans | 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. |
| Object Plans | Query plans generated by creating a stored procedure, function, or trigger. |
| Bound Trees | 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. |
Example
You begin to explore the query performance counters in this object using this T-SQL query on the sys.dm_os_performance_counters dynamic management view:
SELECT * FROM sys.dm_os_performance_counters
WHERE object_name LIKE '%Plan Cache%';