sys.dm_exec_query_parallel_workers (Transact-SQL)
Applies to: 
SQL Server 2016 (13.x) and later
Azure SQL Database
Azure SQL Managed Instance
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 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.
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)