It is all the same with server applications-they all need memory to be able to run. However, SQL server is different with other server applications in one aspect —it allows the user to decide how much memory he can use. This is an advantage because SQL server needs as much memory as it can handle. SQL Server memory options are manipulated in the GUI or with the sp_configure procedure by adjusting the "max server memory (MB)" setting.
How is this done?
The good news is that a user can configure SQL Server to use above 2 GB of RAM unlike other applications. This can be done by enabling the AWE (Address Windowing Extensions) memory setting. A user can either use the same memory screen or he can use the sp_configure procedure by changing the "AWE enabled" setting. However, the user must first enable the “show advanced options” setting before he can use either option.
Recommended amount of SQL Server memory
There is an old saying that when a user is in doubt on the right amount of SQL server memory, then he just have to buy more. With SQL Server, a user needs a minimum requirement of 512 MB of RAM in the SQL Server and 1 GB of RAM for Microsoft.
However, some professionals recommend at least 1.5 GB of RAM with 1 GB of RAM for SQL Server and 512 MB of RAM for Windows. Why is this so? Some professionals have experienced that when Windows doesn’t have enough memory and SQL server has used all its memory, the SQL server runs as if it is short in memory.