sys.dm_db_session_space_usage
Returns the number of pages allocated and deallocated by each session for the database.
Note
In SQL Server 2005, this view is applicable only to thetempdb database.
| Column name | Data type | Description |
|---|---|---|
session_id |
smallint |
Session ID. session_id maps to session_id in sys.dm_exec_sessions. |
database_id |
smallint |
Database ID. |
user_objects_alloc_page_count |
bigint |
Number of pages reserved or allocated for user objects by this session. |
user_objects_dealloc_page_count |
bigint |
Number of pages deallocated and no longer reserved for user objects by this session. |
internal_objects_alloc_page_count |
bigint |
Number of pages reserved or allocated for internal objects by this session. |
internal_objects_dealloc_page_count |
bigint |
Number of pages deallocated and no longer reserved for internal objects by this session. |
Permissions
Requires VIEW SERVER STATE permission on the server.
Remarks
IAM pages are not included in any of the allocation or deallocation counts reported by this view.
Page counters are initialized to zero (0) at the start of a session. The counters track the total number of pages that have been allocated or deallocated for tasks that are already completed in the session. The counters are updated only when a task ends; they do not reflect running tasks.
A session can have multiple requests active at the same time. A request can start multiple threads, tasks, if it is a parallel query.
For more information about the sessions, requests, and tasks, see sys.dm_exec_sessions, sys.dm_exec_requests, and sys.dm_os_tasks.
User Objects
The following objects are included in the user object page counters:
- User-defined tables and indexes
- System tables and indexes
- Global temporary tables and indexes
- Local temporary tables and indexes
- Table variables
- Tables returned in the table-valued functions
Internal Objects
Internal objects are only in tempdb. The following objects are included in the internal object page counters:
- Work tables for cursor or spool operations and temporary large object (LOB) storage
- Work files for operations such as a hash join
- Sort runs
Physical Joins
.gif "Physical joins for sys.dm_db_session_space_usage")
Relationship Cardinalities
| From | To | Relationship |
|---|---|---|
dm_db_session_space_usage.session_id |
dm_exec_sessions.session_id |
One-to-one |
Examples
For examples that use the sys.dm_db_session_space_usage view, see Troubleshooting Insufficient Disk Space in tempdb.
See Also
Reference
Dynamic Management Views and Functions
Database Related Dynamic Management Views
sys.dm_exec_sessions
sys.dm_exec_requests
sys.dm_os_tasks
sys.dm_db_task_space_usage
sys.dm_db_file_space_usage
Other Resources
Troubleshooting Insufficient Disk Space in tempdb