I'm trying to understand more about the memory usage for SQL Server. I can't seem to figure out what's exactly stored in the memory buffer. My setup is a Windows Server 2008 x64, 8 GB RAM, SQL Server 2008 standard R2, maximum SQL Server memory 6000 MB.
After running SQL Server a couple of hours, the resource monitor shows
sqlservr.exe has used about 6000 MB of memory, but when I check the usage for data and plan caches I get less than 6000 MB:
Cached plans 2541 MB
Database data cached 2706 MB
Total 5247 MB
sys.dm_os_buffer_descriptors to find these values, so from these values I don't know what the 750 MB are used for... I don't think SQL Server is reserving memory since this is a x64 machine... Am I missing something here?