I'm currently using 8GB RAM on my desktop and I was wondering if I need a page file more than 400MB to allow my PC to run optimally.

I don't use a SSD so if my OS decides to use the page file automatically then it could stop my computer running like it could.

400MB is the minimum (to allow error info to be kept safe in case of a problem) and 16MB bare minimum the PC will let you use.

I know people who say they run without a page file at all, is this really the height of performance?IG should be more than adequate...
Hint set the min and max #'s to the same value.IG?One Gig.Windows can do some really weird things without any page file at all. The often given advice of 2.5 times your RAM size is no better or worse than any other. Better if it is on a different physical hard drive than the system drive. The only way the size of the page file will make the PC's performance less than "optimal" is if you make it too small.
Would it be safe to turn the page file off and see how my computer runs?  Would I just check tic the "no paging file" line and click "OK?"  Why are you even asking this? Windows was designed to use virtual memory. Where did you get the idea that it would run better without a page file? Your computer will not instantly break if you disable the page file, but be prepared for plenty of crashes. Some people have the over-simplified idea that the page file is REPLACEMENT for RAM that the computer has not got, and, now that PCs have some "large" amount - 4, 8,16 GB or more, people might as well stop using it. The truth is more complicated. Many programs are written to use a pagefile, and consider this: most programs when requesting memory request much more than they will ever need (a program like WMP might request as much as 300MB for example). This requested memory often doesn't get get used, and so it gets flagged as "can go in pagefile" but because you probably never use it there's no performance penalty.

However, if you have no pagefile, this requested memory has to be fully allocated in RAM. So WMP suddenly needs 300+MB of RAM allocated to it (and therefore not to other programs) even though it might not be being used. At this point 8GB becomes very small if you're trying to play a game and leave itunes/azureus running in the background because "I've got 8GB, I can multitask". A bigger program like Photoshop will request gigs of RAM at a time.

The big problem with DISABLING your pagefile is that once you've exhausted the available RAM, your apps are going to start crashing, since there's no virtual memory for Windows to allocate—and worst case, your actual system will crash or become very unstable. When that application crashes, it's going down hard—there's no time to save your work or do anything else.

In addition to applications crashing anytime you run up against the memory limit, you'll also come across a lot of applications that simply won't run properly if the pagefile is disabled. For instance, you really won't want to run a virtual machine on a box with no pagefile, and some defrag utilities will also fail. You'll also notice some other strange, indefinable behavior when your pagefile is disabled—in my experience, a lot of things just don't always work right.

For this reason, a pagefile of a few hundred MB is as pointless as no pagefile at all.

Windows 7 includes a file caching mechanism called SuperFetch that caches the most frequently accessed application files in RAM so your applications will open more quickly. It's one of the many reasons why Windows 7 feels so much more "snappy" than previous versions—and disabling the pagefile takes away RAM that Windows could be using for caching.

Leave it set to 1.5 - 2.5x your RAM. If you want to play around with it, fine by me, and I'll even apologise for posting crap if you show me a single benchmark that shows any benefit whatsoever from doing so.

The point is, the point: Windows is simply not designed or optimised to run with a tiny/without any pagefile.


Are you short on disc space? If not, just leave it alone.In addition to what ST notes, not having a pagefile also changes a bunch of assumpions made by the Memory manager. I forget the specifics but I recall it changes the minimum size of a commited piece of RAM from 4KB to something ludicrous like 64K.

A lot of this "run without a pagefile" nonsense was started by JEFF Atwood in his typical "I messed around with it so now I'm an expert" style.
 

Basically, what running without a pagefile is it effectively makes every single allocation of memory become the functional equivalent of having been had  VirtualLock called on it. VirtualLock() is called by an application to say "OK, this piece of memory is important to me, so don't swap it to disk". Of course if you don't have a pagefile than every single piece of memory allocated can't be swapped to disk anyway. On the other hand, as ST also notes many applications will allocate larger chunks of space. These are allocated using VirtualAlloc() (or a functional equivalent)

Basically, what you get is this:

Application: "Hey, Memory manager, could you toss me a pointer to 500MB of memory?"
VMM: Sure, here you go.

At that point, the memory isn't really "allocated"; that is, the VMM hasn't comitted it; it's just reserved space in that applications Virtual Address space for the RAM. the memory doesn't actually get consumed unless the application uses that memory, at which point it get's committed; and if other applications are switched to and used more, that page could get swapped to disk to make room for another applications memory.
Of course, without a pagefile, all allocations of memory are commits to physical memory. The Virtual Memory manager is specifically designed for fact  that All Applications are basically "given" usually 2GB of Virtual Memory. Windows let's it do what it pleases in those 2GB and like a caring mother will PUT away the toys when the application hasn't been using them. Then when the application goes back to it "I wanna play with that piece of Memory at Virtual address 0x3566313!" the VMM, again, like a caring mother, takes that piece of data out of the pagefile and puts it back into physical memory, so the application can play with it. Of course where in physical memory it puts it doesn't matter since it just maps it into the processes virtual address space. Without a pagefile, you basically end up with a harried mother who has nowhere to put away the toys when the kids are done with them, so you end up with a giant mess.


Additionally, you have two things, the Paged and Non-paged pools (info). Basically, the conclusion one ought to reach from the post is that Page files are a necessary part of any modern Protected-mode operating system, in that they prevent depletion of the page pool, which contributes to a faster system.


Also: Don't Throw those paging files away.


Again, though, I find it interesting all the crap I found while trying to google for references Naturally, the results were overrun by crap postings and blog posts by Mr.Tim the expert PC repair technician offering his expert opinion on a subject he is clearly ignorant on, which is somewhat typical when it comes to things like this. It's unfortunate that they seem to top the search results, too. Quote from: patio on January 06, 2012, 09:20:49 AM

IG should be more than adequate...
Hint set the min and max #'s to the same value.

We can argue til the cows come home...

Yours is based on nothing.

Erm, gents, let's not be presumptuous here.  We're all trying to help.  Differences of opinion can be handled graciously, surely.