Question : All memory used by SQL Server 2008 + Reporting Services

We have a database running on SQL Server 2008. On the server we were initially using 4 Gb. Because all memory was used bij SQL Server / Reporting Services, we tried to increase the amount of memory. But even with 15 Gb, all memory is used by SQL Server / Reporting Services.

This doesn't seem normal to me. How to identify the problem and how to solve the memory problem?

Answer : All memory used by SQL Server 2008 + Reporting Services

SQL Server can take all the memory available in the box if only there is  large enough database (a database with data size bigger than the amount of RAM). It's normal because SQL Server tries to store as much data in the buffer cache as it can (to avoid physical reads from disks). To prevent SQL Server from taking all the memory for its buffer cache you can set the maximum server memory setting for the SQL Server instance. See here for details: http://msdn.microsoft.com/en-us/library/ms178067.aspx (there is a code at the bottom of the page which you can use as an example).