sys.dm_db_task_space_usage (Transact-SQL)

Applies to: yesSQL Server (all supported versions) YesAzure SQL Database YesAzure SQL Managed Instance yesAzure Synapse Analytics yesParallel Data Warehouse

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 Parallel Data Warehouse, 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.
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, Parallel Data Warehouse

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 or the Azure Active Directory admin account is required. On all other SQL Database service objectives, the VIEW DATABASE STATE permission is required in the database.


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

Physical joins for sys.dm_db_session_task_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

See Also

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)