How much memory is my windows app really using?
I have a long-running memory hog of an experimental program, and I'd like to know it's actual memory footprint. The Task Manager says (in windows7-64) that the app is consuming 800 mb of memory, but the total amount of memory allocated, also according to the task manager, is 3.7gb. The sum of all the allocated memory does not equal 3.7gb. How can I determine, on the fly, how much memory my application is actually consuming.
Corollary: What memory is the task manager actually reporting? It doesn't seem to be all the memory that's allocated to the app itself.
Answer
As I understand it, Task manager shows the Working Set;
working set: The set of memory pages recently touched by the threads of a process. If free memory in the computer is above a threshold, pages are left in the working set of a process even if they are not being used. When free memory falls below a threshold, pages are trimmed from the working set.
via http://msdn.microsoft.com/en-us/library/cc432779(PROT.10).aspx
You can get Task Manager to show Virtual Memory as well.
I usually use perfmon (Start -> Run... -> perfmon) to track memory usage, using the Private Bytes counter. It reflects memory allocated by your normal allocators (new/HeapAlloc/malloc, etc).