12GB and pagefile

cpui

Distinguished
Jul 11, 2008
8
0
18,510
0
I just installed OZC 12 GB Platinium with XP 64. i will use this system for Video/Photo Editing (Adobe CS4+ Lightroom). I not sure how to manage the Page File? One of my friend suggest me that disable page file will improve performance. One of my friend advise me again that i did not need 12 GB? Can you guys help me out with your expertise?

Here is my build

i7 920
WD Vraptor 150 GB (OS)
2x WD Blue 320 GB (Raid O)
Quadro 370

Thank for your help


 
Leave your page file alone, some programs use your disk for a scratch file anyway, no matter what you do with your pagefile, or how much memory you have.
And your friend is right, 6 gig of memory should be plenty, even for a heavy user of
Photoshop, CS4 or just about anything else for that matter. 12 is just a little overkill.
 

lucuis

Distinguished
Apr 21, 2008
1,048
0
19,310
23
What jitpublisher said, some programs want to use the page file regardless of if it's disabled or not. And if it's disabled those programs can get cranky :)

I have disabled my page file before, since i have 8gb of ram, and i do remember having a couple crashes but i can't say for sure if it was because my page file was disabled. At the time i was in the process of overclocking and finding stability. So it really could have been anything.

Best just to leave it alone. I didn't notice any performance advantage with or without the page file being disabled.

 

mikrev007

Distinguished
Oct 28, 2008
264
0
18,790
3
There is no way that an application can write directly to the pagefile (there is no API for that). So it makes little sense to say that it will "page" to it.

My point is: no application will crash because there is no pagefile to write data to (data will just always be written only to physical ram). It might crash, if there is no more memory, but that is another issue.
 



You have read something into this that is not there, and you apparently have no knowledge of the programs the OP is using. And yes, Windows needs a pagefile. It WILL cause problems if you turn it completely off. In the latest service packs, even if you do turn it off, Windows will turn it back on the background. You can set it to smaller size, but if Windows thinks the size is too small, it will simply override your settings anyway.
 

mikrev007

Distinguished
Oct 28, 2008
264
0
18,790
3
No, Windows doesn't *need* a pagefile. I know many people likes to say this in forums, and others will pick this up and spread it further around. But a pagefile is NOT a requirement. Research how memory management works.

And yes, if you disable the pagefile it is disabled. Windows won't just turn it back on.

PS: I am not arguing that it is a good idea to have it disabled, I'm just saying it is not a requirement for operation.
 

mitch074

Distinguished
Mar 17, 2006
1,957
31
19,840
21
@mikrev007: not exactly - it's true that no API allows an app to write to the page file directly (it requires SYSTEM authorizations, and all "Certified for Windows XP" apps are required to run in 'pure' user space, apart from services - so it's transparent). However, some apps try to allocate as much RAM as they can on load, and when page files are enabled Windows can report several Gb of space. So, if you have, say, 4 Gb of RAM with PF disabled, and the app tries to allocate 8 Gb, it may crash due to 'insufficient memory'.

Granted, this doesn't happen very often (even less with 12 Gb of RAM), but it's there.

However, Windows itself works better if it has a page file available, because it pre-allocates craploads of RAM to any app that starts, and also uses a lot of hard disk caching (as such, a lot of unneeded apps that get loaded in RAM are paged away to make room for said disk caching).
Through trial and error, I've found that installing your system fully, rebooting it and waiting for the harddisk to stop tharshing after boot, and THEN noting how much RAM is used, is a good starting point to evaluate your swap file size (if you have enough RAM to run even the most demanding app from RAM, obviously).

Case in point: reboot your system (fresh boot), open the Task Manager, and note how much RAM is used/allocated: let's say, Vista, an antivirus, and a few loaders, around 700 Mb. Then, open your System settings, Page file size: set a (fixed) size of 700-800 Mb (min and max). Reboot.

This way (if your system was not fragmented), you'll have a one-segment page file (it's faster to access) where the kernel can page away everything that is loaded at boot but usually unneeded, and you'll prevent Windows from swapping away running applications while not wasting 700 Mb of RAM space that'd be better off used as disk cache.

Or, you switch to Linux and you let a real RAM manager change your life :p
 

mikrev007

Distinguished
Oct 28, 2008
264
0
18,790
3
mitch074, now you are talking about insufficient memory issues. And yes, the pagefile can help that. I addressed the statement that a pagefile was a "requirement" for Windows and some applications to run - even though enough memory was available.
 

mitch074

Distinguished
Mar 17, 2006
1,957
31
19,840
21
@mikrev: not exactly - there's a difference between how much RAM an app allocates and how much it uses (you can have both columns displayed side by side in the Task Manager's Process monitor: Used and Allocated).

In fact, a 64 Kb (!) app can allocate 12 Gb of RAM and actually use less than a megabyte; if it contains an instruction that tells it to exit if 12 Gb of RAM are not available, it exits.

Slightly sloppy coding, for sure (an even more sloppy coding technique is to not check available RAM on load, and then crash and burn when the app runs out of RAM while in use ); but, if you leave Windows manage its swap file size, it will actually report more than enough for this kind of software to run without error on most systems (free RAM + available disk space on a disk volume hosting a dynamic swap file).

Let's take one very simple case: you start World of Warcraft, with all options enabled, and you go to Dalaran (heavy load). Then, you open your task manager, and look at how much RAM Wow.exe takes up: around 975 Mb. Then, you look at allocated RAM: 2 Gb (max. ram that a 32-bit, non-PAE aware application may allocate: 2^(32-1)).

In short, a software can return an 'out of memory' error not because it won't fit in RAM in practice, but because allocatable RAM is too low for it (this is actually a limitation set by the program's programmer, or his compiler).
 

mikrev007

Distinguished
Oct 28, 2008
264
0
18,790
3
You are still talking about insufficient memory issues.

And I still addressed the statement that the pagefile it required, because some applications uses it no matter what. Which is false.
 

Oakley707

Distinguished
Jan 21, 2008
109
0
18,690
1
Just to add my $.02. I have Vista 64 Ultimate and have turned off the page file since I built the computer in January. I have had ZERO crashes / freezes. Maybe it is because of Vista, but when I am using Photoshop, games, or even video editing. I agree that a page file is NOT necessary.

I must note that I have heard HORROR stories of XP 64 bit and compatibility issues, maybe you should upgrade to Vista x64? Just a thought.

 

cpui

Distinguished
Jul 11, 2008
8
0
18,510
0
Oakley707: I feel like it is too late to go with Vista, i'm rather to wait win7, I'm just want to skip Vista. OK let's go back to my question..
So windows suggest x1.5 size of RAM for page file. But it look like it's not correct for more than 6GB who install in their system? I'm i on the right track?
 

ASK THE COMMUNITY

TRENDING THREADS