Munku

Can someone tell me the max windows xp allows and what I should set mine at?

p4 2.0 ghz
1024 megs ram.

Is there any reason why I shouldn't go beyond 2x my physical ram? Why not 4 gigs?

schnable

I'm not a WinXP expert, but I can comment in general.
Virtual Memory is used like physical RAM--when RAM fills up, a program may be "swapped" into virtual memory on the harddisk while it is running in the background. When this program actually does something, or especially when you are interacting with it, it needs to swapped back into real RAM. All of this swapping is not exactly quick, due to overhead of the swap process in general, and espcially because a harddrive is much slower than RAM and tends to be a bottleneck in an otherwise fast system. If you had 3gb worth of programs running, the constant swapping would slow your system down considerably (you have probably noticed your harddrive "thrashing" at points in time, swapping causes this).

Additionally, why the hell do you need 3gb of memory?? Unless you are running a very complex scientific or graphical program that stores a lot of data in memory, you are probably never going to come close to utilizing all that memory, thus wasting harddrive space. I also remember older versions of windows seemed to have a problem overutilizing virtual memory when there was plenty of physical ram, again causing harddrive thrashing and overall slow performance when it was unnecessary. I haven't used XP that much so I can't comment on this particular aspect.

Assuming that your operating system has good virtual memory algorithms, setting a VM size that large will not be particularly harmful, but will be wasteful.

bingle

I'm not sure what the maximum size is in XP, but the reason you might not want a larger one is that it will take up that much disk space - so having a 4 gig page file means you have 4 gigs less of HDD space.

The old answer used to be 2x your system memory, but these days with the amount of RAM people have, page files have become less important - you're probably going to fit everything you need into 1 gig of memory, and if you don't you're probably not going to need another 2 gigs on top of that.

In any case, for gaming you want to avoid use of the page file if at all possible - HDD access is, of course, a lot slower than RAM access.

Bingle

Xepidemic

you have a gig of ram! unless your working with extremely large files chances are you arent even using your virtual memory. you could even disable virtual memory if you wanted. usually virtual memory should be 1.5 times your ram. so for you it would be 1536. or you could always get a program to control your memory such as cacheman xp.

TheAgent

I wouldnt worry about XP's maximum VM size - its pretty big... I forget the exact number.

Here's what I can contribute:
You have 1GB of RAM, so unless you're working with large amounts of data, you're not getting much use out of your pagefile. I would not suggest disabling it, though, as Windows XP will page unused data to your pagefile in order to leave plenty of free memory for itself and your applications to use (this is in constrast to UNIX/Linux VM management which keeps everything in physical memory until its totally full). You could set your pagefile to 2GB if you want, but you'll never really need any of that (and you might be able to put that space to better use), so I would suggest setting it either to 1GB or even a bit less. Typically, it is not recommended to have less VM than physical memory, as physical memory gets dumped to VM when the OS crashes... but if you're not concerned with using that data for debugging purposes, feel free to set your VM to 512MB or so.

Hope that helped.

Munku

Just realized this is in the wrong section! Dangit, meant to be in Computers. I mostly use my comp to play games. EQ2 and the likes. So that sort of thing is ram intensive really.

TheFu

Let windows manage it. I think that is what Microsoft recommends.

bingle

That is what Microsoft recommends, but that's mostly so that naive users don't mess up their settings :-) It is better to set your page file size to a static amount, rather than letting Windows resize it, because when that resize occurs it is very slow - the OS has to find enough space for the additional data, and write it to disk, and then size it down again when you're done, and so forth. Also, if it has dynamic size, it will become fragmented over time when there isn't enough room for the whole file as one large block on the disk, and this can lead to other performance problems.

Bingle

Edit: although, actually, this is only for users who are most concerned with runtime performance. If you're more concerned with disk space usage, you're better off either disabling it, or letting Windows manage it for you.

Robaggio

Bingle speaks the truth.

You don't want your hard drive thrashing to resize the page file in the midst of a heated battle. Put shackles on that pagefile: set it's min/max to the same size. You'll be amazed at the performance increase. A common rule of thumb is setting the pagefile to be 1.5X the ammount of ram you have. (Though I wouldn't go higher than 1gig in all cases. There is such a thing as overkill

For added speed, set the pagefile on a separate hard drive all together. I have a speedy 2gig hard drive (11000rpm!) used specifically for my page file.

Also, I don't recommend disabling the pagefile. There are cases where programmers explicitly use virtual memory rather than physical. For example, Doom3 does this because of the way their files are decompressed into memory.