sys.dm_db_task_space_usage (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW)

Returns page allocation and deallocation activity by task for the database.


This view is applicable only to the tempdb database.


To call this from Azure Synapse Analytics or Analytics Platform System (PDW), use the name sys.dm_pdw_nodes_db_task_space_usage. This syntax is not supported by serverless SQL pool in Azure Synapse Analytics.

Column name Data type Description
session_id smallint Session ID.
request_id int Request ID within the session.

A request is also called a batch and may contain one or more queries. A session may have multiple requests active at the same time. Each query in the request may start multiple threads (tasks), if a parallel execution plan is used.
exec_context_id int Execution context ID of the task. For more information, see sys.dm_os_tasks (Transact-SQL).
database_id smallint Database ID.

In Azure SQL Database, the values are unique within a single database or an elastic pool, but not within a logical server.
user_objects_alloc_page_count bigint Number of pages reserved or allocated for user objects by this task.
user_objects_dealloc_page_count bigint Number of pages deallocated and no longer reserved for user objects by this task.
internal_objects_alloc_page_count bigint Number of pages reserved or allocated for internal objects by this task.
internal_objects_dealloc_page_count bigint Number of pages deallocated and no longer reserved for internal objects by this task.
pdw_node_id int Applies to: Azure Synapse Analytics, Analytics Platform System (PDW)

The identifier for the node that this distribution is on.


On SQL Server and SQL Managed Instance, requires VIEW SERVER STATE permission.

On SQL Database Basic, S0, and S1 service objectives, and for databases in elastic pools, the server admin account, the Microsoft Entra admin account, or membership in the ##MS_ServerStateReader## server role is required. On all other SQL Database service objectives, either the VIEW DATABASE STATE permission on the database, or membership in the ##MS_ServerStateReader## server role is required.

Permissions for SQL Server 2022 and later

Requires VIEW SERVER PERFORMANCE STATE permission on the server.


IAM pages are not included in any of the page counts reported by this view.

Page counters are initialized to zero (0) at the start of a request. These values are aggregated at the session level when the request is completed. For more information, see sys.dm_db_session_space_usage (Transact-SQL).

Work table caching, temporary table caching, and deferred drop operations affect the number of pages allocated and deallocated in a specified task.

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

Diagram of physical joins for sys.dm_db_task_space_usage.

Relationship cardinalities

From To Relationship
dm_db_task_space_usage.request_id dm_exec_requests.request_id One-to-one
dm_db_task_space_usage.session_id dm_exec_requests.session_id One-to-one

Next steps

Dynamic Management Views and Functions (Transact-SQL)
Database Related Dynamic Management Views (Transact-SQL)
sys.dm_exec_sessions (Transact-SQL)
sys.dm_exec_requests (Transact-SQL)
sys.dm_os_tasks (Transact-SQL)
sys.dm_db_session_space_usage (Transact-SQL)
sys.dm_db_file_space_usage (Transact-SQL)