Many of the performance and reliability gains of Microsoft SQL Server are achieved through close integration with Microsoft Windows NT Server.
Microsoft SQL Server is a Win32 application that runs on the Windows NT Server or Windows NT Advanced Server (NTAS) operating systems. In rare situations when SQL Server is running a compute-bound operation, the interactive console responsiveness of Windows NT may be diminished. This article discusses characteristics of the Windows NT process scheduler (often called thread scheduler or thread dispatcher) that relate to this behavior.
Windows NT Server and NTAS use the same system of scheduling Win32 processes and threads. With Windows NT, the unit of scheduling is the thread—hence, the term thread scheduling or dispatching is sometimes used. In other operating systems, this is usually called process scheduling. However, the term "process" will be used in this discussion, where appropriate. The unit of scheduling time is called the time slice or quantum.