[DigeratiPrime]

the "commit charge" in task manager is not a good measurement of ram usage: 1) it doesnt really measure actual memory usage, 2) you can easily manipulate this number by adjusting the virtual memory size. I emphasize the latter because you can install the same Windows on two different machines and if they have different amounts of RAM the Commit Charge will differ.

[DigeratiPrime]

Here is a screenshot taken from a just finished install of xp in vmware.
All components removed with nLite 1.3 RC, VM has 256MB of ram.
Here XP is using 54,472K of memory (261,616 - 207,144).



All services disabled and Virtual Memory disabled.
Using 43,132K of memory (261,616 - 218,484).


I could probably have gotten this lower without integrating sp2, ryanvm update pack, and xpize.
this was just a test, my 'host' machine uses a bit more.

[nitroshift]

337 MB. Running: Technisat Server4PC, IE7, NOD32 (just for a quick scan), Screamer Radio.

[Zxian]

DigeratiPrime, on Jan 7 2007, 07:34 PM, said:

the "commit charge" in task manager is not a good measurement of ram usage: 1) it doesnt really measure actual memory usage, 2) you can easily manipulate this number by adjusting the virtual memory size. I emphasize the latter because you can install the same Windows on two different machines and if they have different amounts of RAM the Commit Charge will differ.

The same can be said of this entire thread. The number that people give doesn't really mean anything without knowing how much RAM the system has to begin with. Obviously, my system that uses 300MB of RAM won't on one that only has 256MB to start with. Windows will properly distribute the memory allocation for those processes that require it the most.

[LLXX]

Zxian, on Jan 10 2007, 01:46 AM, said:

Obviously, my system that uses 300MB of RAM won't on one that only has 256MB to start with.

Windows would fill up the physical RAM and then swap the remaining 50MB or so to the pagefile.

This post has been edited by LLXX: 10 January 2007 - 02:23 AM

[Zxian]

No - that's not true. The physical RAM wouldn't be completly filled up. Windows always reserves free RAM for new applications. My mother's computer only has 256MB of RAM, and with XP, Avast, and Comodo installed, it's still got 100MB free. If I close the two bigger (in terms of RAM usage) startup items on my computer, I still don't get down to anywhere near 150MB used.

Take a computer system with 256MB of RAM and install a basic installation of Windows. Look at the amount of free memory. Now upgrade to 512MB. Look at the free memory again. It will not have increased by 256MB.

[ripken204]

well how exactly does pagefile work? it makes absolutely no sense to me. b/c i could have 1.7gigs of ram fre and i could somehow be using 700mb of pagefile...

[DigeratiPrime]

thats why I turn off the page file (virtual memory) and use my excess ram. no more slow start menu or trim on minimize etc.
I have seen this cause a program to crash though, CIV4 after an hour, with Photoshop, Firefox, etc running on 1GB

[Zxian]

ripken204, on Jan 10 2007, 05:12 PM, said:

well how exactly does pagefile work? it makes absolutely no sense to me. b/c i could have 1.7gigs of ram fre and i could somehow be using 700mb of pagefile...

DigeratiPrime, on Jan 10 2007, 05:33 PM, said:

thats why I turn off the page file (virtual memory) and use my excess ram. no more slow start menu or trim on minimize etc.
I have seen this cause a program to crash though, CIV4 after an hour, with Photoshop, Firefox, etc running on 1GB

This has been discussed so many times!

Search Results

For further reading...

[[deXter]]

First lets get some things sorted out. The "PF Usage" shown in the Windows Task Manager IS NOT the real PF usage- its actually the Commit Charge.

Taken from Windows' Performance Monitor:

"Committed memory is the physical memory in use for which space has been reserved in the paging file should it need to be written to disk. The commit limit is determined by the size of the paging file. If the paging file is enlarged, the commit limit increases, and the ratio is reduced)"

"Available MBytes is the amount of physical memory available to processes running on the computer, in Megabytes. It is calculated by adding the amount of space on the Zeroed, Free, and Stand by memory lists. Free memory is ready for use; Zeroed memory are pages of memory filled with zeros to prevent later processes from seeing data used by a previous process; Standby memory is memory removed from a process' working set (its physical memory) on route to disk, but is still available to be recalled."

So basically, Available MBytes should provide an accurate info how much physical memory is free, and this is the same value that's shown under Task Managers' Available Physical Memory. If it shows 102400K, that means you have 100MB free memory in your RAM ready for use, never mind if it includes the reserved and the cached portions of existing processes. What this means is that if you're about to load a program that would use upto 100MB, you're good to go without much swapping taking place. However some amount of swapping would take place to reserve physical memory for other processes. Therefore, to prevent significant swapping while running time-critical apps like games, make sure your free memory is a good amount more than what the game/app uses.

But this brings us to the question on how to accurately know how much non-shared (private) memory is actually being used by a process. You can find it out by looking at the VM Size coloumn in task manager (View -> Select Coloumns -> Virtual Memory Size). This is also called as private bytes, as show in Sysinternals' Process Explorer. And as you can see in the picture, what task manager normally reports as mem usage is really the working set (physical memory in use).



And now the answer that everyones been waiting for: How to know the actual (total) memory usage: The solution lies in Performance Monitor (Start -> Run -> perfmon). Add the Paging File object. You'll see the %usage of your pf. So to get the actual memory used by your PC: (Total - Available MB) + (%usage * pf size / 100). In the screenshot below, I have 138 MB free RAM and 37% used PF. I have a total of 512 MB RAM and 512 MB PF. Therefore my actual usage would be (512 - 138) + (37 * 512 / 100) = 563.44 MB.

This post has been edited by [deXter]: 11 January 2007 - 04:33 AM

[Camarade_Tux]

It takes 1GB out of 2GB!


Maybe that I should close VMWare.
But opensuse takes 2GB out of 2GB.
If I start UT2k4, it takes 10 seconds to load. If I close it and then open it again it starts within 3 seconds. ^^
Maybe because only 13MB are being paged.

This post has been edited by Camarade_Tux: 13 January 2007 - 03:50 AM