Returns information about all the waits encountered by threads that executed for each session. You can use this view to diagnose performance issues with the SQL Server session and also with specific queries and batches. This view returns session the same information that is aggregated for sys.dm_os_wait_stats (Transact-SQL) but provides the session_id number as well.
Applies to: SQL Server 2016 (13.x) and later versions.
|Column name||Data type||Description|
|session_id||smallint||The ID of the session.|
|wait_type||nvarchar(60)||Name of the wait type. For more information, see sys.dm_os_wait_stats (Transact-SQL).|
|waiting_tasks_count||bigint||Number of waits on this wait type. This counter is incremented at the start of each wait.|
|wait_time_ms||bigint||Total wait time for this wait type in milliseconds. This time is inclusive of
|max_wait_time_ms||bigint||Maximum wait time on this wait type.|
|signal_wait_time_ms||bigint||Difference between the time that the waiting thread was signaled and when it started running.|
This DMV resets the information for a session when the session is opened, or when the session is reset (if connection pooling),
For information about the wait types, see sys.dm_os_wait_stats (Transact-SQL).
For SQL Server 2019 (15.x) and previous versions, if you have VIEW SERVER STATE permission on the server, you see all executing sessions on the instance of SQL Server; otherwise, you see only the current session.
For SQL Server 2022 (16.x) and later versions, you require VIEW SERVER PERFORMANCE STATE permission on the server.