Database Reference
In-Depth Information
Figure 2-5.
Output of DBCC MEMORYSTATUS
The first data set shows basic allocations of memory and counts of occurrences. For example, Available Physical
Memory is a measure of the memory available on the system, whereas Page Faults is just a count of the number of
page faults that have occurred.
The second data set shows different memory managers within SQL Server and the amount of memory they have
consumed at the moment that the
MEMORYSTATUS
command was called.
Each of these can be used to understand where memory allocation is occurring within the system. For example,
in most systems, most of the time the primary consumer of memory is the buffer pool. You can compare the Target
Committed value to the Current Committed value to understand if you're seeing pressure on the buffer pool. When
Target Committed is higher than Current Committed, you might be seeing buffer cache problems and need to figure
out which process within your currently executing SQL Server processes is using the most memory. This can be done
using a dynamic management object.
The remaining data sets are various memory managers, memory clerks, and other memory stores from the
full dump of memory that DBCC MEMORYSTATUS produces. They're only going to be interesting in very narrow
circumstances when dealing with particular aspects of SQL Server management, and they fall far outside the scope
of this topic to document them all. You can read more in the MSDN article “How to use the DBCC MEMORYSTATUS
