Tester said:
Hi there,
I am using XP Pro. Why in task manager I cannot add up all running
processes to the actual memory usage? If I add all there, including
checking show processes from all users checkbox they still do not add
up to what I see in performance tab, PF usage? Thanks.
The PF Usage value reported by Task Manager includes a considerable
amount of "phantom" usage in the form of unused portions of memory
allocation requests.
By design Windows must allocate memory address space to fulfill all of
the memory allocation requests that are issued by Windows components,
application programs, device drivers, etc. And also by design these
items ask for memory allocations that are larger than what they
ordinarily need under normal circumstances. Windows handles this
situation by allocating addresses in RAM only to those portions of the
requests that are actually used, and maps the unused portions to
available locations in the paging file. Note that this mapping of
unused allocation requests to the paging file does not require any
actual hard drive activity - all that is needed is to make entries in
the memory mapping tables maintained by the CPU.
Hope this explains the situation.
Good luck
Ron Martell Duncan B.C. Canada
--
Microsoft MVP (1997 - 2008)
On-Line Help Computer Service
http://onlinehelp.bc.ca
Syberfix Remote Computer Repair
"Anyone who thinks that they are too small to make a difference
has never been in bed with a mosquito."
