sys-dm-exec-query-parallel-workers-transact-sql.md

title	description	author	ms.author	ms.date	ms.service	ms.subservice	ms.topic	f1_keywords	helpviewer_keywords	dev_langs	monikerRange
sys.dm_exec_query_parallel_workers (Transact-SQL)	sys.dm_exec_query_parallel_workers (Transact-SQL)	rwestMSFT	randolphwest	02/24/2023	sql	system-objects	reference	dm_exec_query_parallel_workers_TSQL dm_exec_query_parallel_workers sys.dm_exec_query_parallel_workers_TSQL sys.dm_exec_query_parallel_workers	sys.dm_exec_query_parallel_workers dynamic management view	TSQL	=azuresqldb-current||>=sql-server-2016||>=sql-server-linux-2017||=azuresqldb-mi-current

sys.dm_exec_query_parallel_workers (Transact-SQL)

[!INCLUDE sqlserver2016-asdb-asdbmi]

Returns worker availability information per node.

Name	Data type	Description
node_id	int	NUMA node ID.
scheduler_count	int	Number of schedulers on this node.
max_worker_count	int	Maximum number of workers for parallel queries.
reserved_worker_count	int	Number of workers reserved by parallel queries, plus number of main workers used by all requests.
free_worker_count	int	Number of workers available for tasks. Note: every incoming request consumes at least 1 worker, which is subtracted from the free worker count. It is possible that the free worker count can be a negative number on a heavily loaded server.
used_worker_count	int	Number of workers used by parallel queries.

Permissions

On [!INCLUDEssNoVersion_md] 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.

Examples

A. Viewing current parallel worker availability

SELECT * FROM sys.dm_exec_query_parallel_workers;  

See Also

Dynamic Management Views and Functions (Transact-SQL)
Execution Related Dynamic Management Views and Functions (Transact-SQL)
sys.dm_os_workers (Transact-SQL)