What is 'memory usage'?

I see lots of posts that say something like the following:

So, what exactly is memory usage... Virtual Memory... Working Set...?

For example, if I use Process Explorer and I look at cfp.exe (COMODO Firewall Pro 2.4.18.184).

So, is 'memory usage'...
1) 13,272K
2) 20,852K
3) 62,844K
4) 15,384K
5) 10,732K
6) 4,652K
7) 3,984K
15,808K
9) None of the Above

15,384K... right?

If I run pmon.exe (on the XP CD in the \SUPPORT\TOOLS\SUPPORT.CAB file), it says 'Mem Usage is 15384'.

Mike

 

According to Windows, Memory Usage would be the figure in the Mem Usage column in Task Manager.
This monitors the amount of RAM that each program uses.

http://www.urs2.net/rsj/computing/imgs/mem_1.gif

For the other items, some reading is necessary to understand everything. A good starting reference I've used in the past is:

http://www.microsoft.com/technet/prodtechnol/Windows2000Pro/reskit/part6/proch28.mspx?mfr=true

When I installed Win2K I read everything I could on this (and have forgotten most of it) because after playing with tweaks and memory managers, I realized that Windows does a pretty good job itself, thank you very much!

The big change from Win9x is the way Processes and Threads are dealt with. In your screen shot, notice GDI and USER handles. Remember Resource leaks? No matter how much physical RAM you had in your system, it was still possible to run out of System Resources, and your system could grind to a halt.

Now, I can run as many programs as I want: usually 6 - 8 open all of the time:

http://www.urs2.net/rsj/computing/imgs/mem_2.gif

As far as RAM usage - I experimented with opening stuff until my RAM meter (upper right in the screen shot) showed my 1GB of RAM was depleted, and I never experienced any slowdown. In normal usage, I never deplete my RAM. Photoshop and Opera use more RAM than my other programs, but I don't know if those figures are high-low-optimum; all I know is that I've never experienced any problems. So, I never understood what all the fuss was about concerning Memory Usage.

None of my programs show any significant amount of CPU just standing open, leaving the Maximum for each program to use when it has the focus. However, if you use an AV scanner, it might hog CPU sometimes, affecting your working in other programs competing for CPU, so monitoring helps here.

For Virtual Memory (page file, Swap file):

Microsoft recommends 1.5 times the size of the physical memory. However, from the article above:

Well, the converse is also true: If you never are short on RAM, you don't encounter paging, hence, no slowdown. I always had my Page file Max & Min = 500MB. More seemed to be a waste of HD space.

However, even in my above test, where swapping evidently occured, I didn't notice a slowdown, so I would think you would have to really push the page file usage to it's maximum to notice something.

From an old article on Win2K - sorry, I no longer have the link:

I'm not familiar with "working set"

Again, search for articles. There is a lot out there, but I would evaluate carefully what you read with your own system, programs, settings, etc.

I gave my examples to show that you don't have to take at face value everything you read. Run your own tests and monitor the results.

If your programs use a lot of memory, add another GB - RAM is cheap these days, compared with years ago!

regards,

-rich

________________________________________________________________
"Talking About Security Can Lead To Anxiety, Panic, And Dread...
Or Cool Assessments, Common Sense And Practical Planning..."

--Bruce Schneier​

 

Thanks for that link.

In reading, I notice I mispoke about my page file size: I have no maximum set. (that was from Win9x days when other factors came into play)

The article states,

regards,

-rich

 

For what it is worth, the memory usage number displayed by Windows Task Manager = the Working Set number in Sysinternals Process Explorer.

http://en.wikipedia.org/wiki/Working_set

Mike