Wait Type PREEMPTIVE_OS_WAITFORSINGLEOBJEC

Wait statistics, in the context of SQL Server, refer to the amount of time that a query spends waiting to access data in the database. When a client application requests data from the database, the request is placed in a queue and the client application must wait for its turn to access the data. The time that the query spends waiting is called a "wait" and is tracked by SQL Server. This information can be used to identify potential performance bottlenecks and optimize the performance of the database. Wait statistics are commonly used by database administrators to diagnose and troubleshoot performance issues in SQL Server.

The PREEMPTIVE_OS_WAITFORSINGLEOBJECT wait type in SQL Server is a type of wait that occurs when a task is waiting for a synchronization object. In SQL Server, synchronization objects are used to coordinate access to shared resources and prevent race conditions. When a task is in the PREEMPTIVE_OS_WAITFORSINGLEOBJECT wait state, it is waiting for a synchronization object to be signaled before it can continue execution. This wait type is typically only seen when synchronization objects are being used in the database.

Applies to

• SQL Server 2012
• SQL Server 2014
• SQL Server 2016
• SQL Server 2017
• SQL Server 2019
• SQL Server 2022

Related Waits

See Also

• More About PREEMPTIVE_OS_WAITFORSINGLEOBJEC