[KBA-00142] High memory usage when using SQL Server databases with Omnicast™
This article explains why the memory usage for the MSDE 2000 or SQL Server 2005 process will steadily increase with time.
When you start SQL Server, SQL Server memory usage continues to steadily increase and not decrease, even when activity on the server is low. Additionally, the Task Manager and Performance Monitor might show that the physical memory available on the computer is steadily decreasing until the available memory is between 4 to 10 MB.
This behavior alone does not indicate a memory leak. This is the intended behavior of the SQL Server buffer pool.
When running on Microsoft Windows, the default memory management behavior of the SQL Server database engine is not to acquire a specific amount of memory, but to acquire as much memory as it can without generating excess paging I/O. The database engine does this by acquiring as much memory as is available, while leaving enough memory free to prevent the operating system from swapping memory.
There is no workaround. This is the normal SQL behavior, as indicated by Microsoft in various articles.
For more detailed information, read this Microsoft support article: http://support.microsoft.com/kb/321363/en-us.