Microsoft SQL Server 2005 performs dynamic memory management based on the memory requirements of the current load and activities on the system. On a Windows Server 2003-based system, SQL Server 2005 can use the memory notification mechanisms that are provided by the QueryMemoryResourceNotification Windows API. On a Microsoft Windows 2000 Server-based system, SQL Server 2005 periodically calculates the free physical memory on the system by using the native Windows API. Based on this information from the QueryMemoryResourceNotification Windows API or from the memory calculation, SQL Server 2005 responds to the current memory situation on a specific system. This provides the following benefits:

• The system does not page out the working set of the SQL Server 2005 process.
• The necessary database pages are available in memory to reduce physical I/O needs.

For more information, see the "Dynamic memory management" topic and the "Server memory options" topic in SQL Server 2005 Books Online.