[Question] - downside to large pagefile?

[Angelico_Payne]

With over 1GB of physical memory u can disable pagefile

Some games however require pagefile even if you have e.g. 2 gigs

so in that case u can temporarily enable it

[atomizer]

With over 1GB of physical memory u can disable pagefile...

do some homework and you'll find that's absolutely NOT recommended for a few very good reasons. also see my post above.

[Angelico_Payne]

atomizer

I agree with some things u said, but u have a very negative attitude towards disabling paging,

e.g. A 2 minute search over the google would tell you that formula for min value 1.5xRAM is not general formula but administred in certain range starting from 256MB, while the max value cannot exceed 4G (unless u have a Suhoi fighterplane )

and if you have 1.5G of RAM, u donnot need pageing enabled unless some program explicitly needs it in which case we can apply your advice of setting permanent small page file ~20MB

Just my too cents...

[Grunth0s]

By default, Windows is unable to deal with anything more than 4GB combined RAM/Pagefile, so a large pagefile will not help anything.

There are however, circumstances that will require additional pagefile size, for example, heavy database servers.

The way round this is to add the -3GB switch to the boot.ini file, which will enable a larger pagefile, and will prove to be a benefit for applications which require it.

[Dwinks]

In short, as stated here before, there isn't any point in having an excessively large page file.

Considering the fact that you are here, asking about this, I would assume that your level of expertise would exclude any need to have a memory dump in case of a crash. I may be wrong, and I don't mean to insult or sound brash, but I am just guessing that a memory dump would't be anything you would need.

I also saw a listing of hardware specs under your first post, which listed 2x1gig of ram. If that is the system you are speaking about, I would recommend no more than about 1gig of page file. Unlike linux swap files, windows doesn't use its page file to store hibernation data, it uses a seperate hibernation file, so you dont need to have a page file larger than ram.

If you have 2 gigs of ram, the page file will never get used, and if it does, it would only be due to a program having a memory leak, and in that case, your system will likely be on its way to crashing or at least needing rebooted, and that program not getting ran until the memory leak gets fixed.

Just leave the page file alone, and if you have already changed it, change it to something reasonable like 768-1536mb or so, more will have absolutely no benefit and possibly be detrimental.

[cluberti]

I'm not getting involved in page file size issues, as there are as many

right answers as there are wrong. However, this statement by nmX is

not correct:

The way round this is to add the -3GB switch to the boot.ini file, which will enable a larger pagefile, and will prove to be a benefit for applications which require it.

You need to use the /PAE switch, not the /3GB switch, to enable page file sizes larger than 4GB (with /PAE enabled, you can make 16TB page files).

However, I strongly suggest NOT using the /3GB switch on ANY machines that do not have processes that need to address more than 2GB of virtual address space. The /3GB switch does NOT have any connotation to actual RAM usage, but to VIRTUAL ADDRESS SPACE usage. This shoves the kernel resources into 1GB of VIRTUAL ADDRESS SPACE, and reduces the nonpaged pool to 128MB (instead of 256MB), the paged pool to 160 - 230MB (rather than 350 - 560MB), and reduces the number of free System Page Table Entries (PTE's) from ~200,000 to 40,000 (or less). All of these things can and do hinder system performance, especially the low nonpaged pool and PTEs - and even more so if you have a higher-end video card (those things eat PTE's for breakfast).

So, check the Virtual Bytes and Private Bytes counters for each instance under the Process object in perfmon - unless you see one process (and not the _Total process) using close to 2GB, DO NOT enable /3GB.

As to /PAE, it's really only useful if you're running Windows 2000 Advanced or Datacenter Server, or Windows Server 2003 Enterprise or Datacenter Edition - these are the only Windows operating systems that can address more that 4GB of RAM. There are some memory issues when using the /PAE switch too, so be sure ALL of your drivers support running in AWE mode, or you'll have problems.

Edited January 26, 2006 by cluberti

[suryad]

Cluberti...very good post. I personally have Windows managing my page file.

[cluberti]

Wise choice .

[gdogg]

there is a very easy way to use /3GB switch, without these errors as I have tested it.

it simple, remove the ntkrnlpa.exe file ( when using less than 3GB ram off coarce is all I have tested)

just using this switch can lower the amount of memory used, by many programs greatly

and also fixes those errors, those might occur from using the pa krnl.

also, this may also work for when using over 3GB of ram, but I am unable to test this obviously.

those who have that amount of ram, may wish to test it.

anyway, just my 2 cents

edit

________________

wow sites been down a while

anyway, let me point out, that these were commit change changes, havn't test, acutally ram usage.

Edited January 27, 2006 by gdogg

[kartel]

I have win9x and use conservative swapfile=1

and this cache mod

and this:

I let windows have at it in here

See the last dark block ?Thats my swapfile, which can grow to 6GB if it wants, then after a reboot its gone, back to this.

(the other dark block temp files that wont budge)

here's whats running:

Now I just installed XP pro on another drive, same hardware, can I do the same style of mods to XP ?

I'd like to eventually use them both, mainly xp to install the games and reboot into 98se to play them.

I also hit F5 at the xp install page and selected "uni-processor acpi" since I just got a "Apic" board,

hopefully this time around xp and my irq's will get along, I'm still not sure on that.

Edited February 2, 2006 by kartel

[Maleko]

I have 2 gbs of ram, i let windows manage the minimum amount recommended, and just put that in the maximum size as well, like said b4, this stps it fragmenting, and if windows needs it, it there to use it.

[nmX.Memnoch]

I'm not getting involved in page file size issues, as there are as many

right answers as there are wrong. However, this statement by nmX is

not correct:

The way round this is to add the -3GB switch to the boot.ini file, which will enable a larger pagefile, and will prove to be a benefit for applications which require it.

You need to use the /PAE switch, not the /3GB switch, to enable page file sizes larger than 4GB (with /PAE enabled, you can make 16TB page files).

Errr...you misquoted

Also, 32-bit Windows can assign more than 2GB to a process if you use the /3GB switch in the boot.ini. This is only useful if you have 3GB or more of RAM though. Windows XP Professional does support the /3GB switch.

The way round this is to add the -3GB switch to the boot.ini file, which will enable a larger pagefile, and will prove to be a benefit for applications which require it.

I didn't bring up /PAE because it isn't supported on Windows XP. Most desktop chipsets don't support anything over 4GB of RAM anyway. Until recently (last year or so) even most workstation chipsets didn't support anything over 4GB of RAM. I know exactly what /3GB does, I was just correcting someone else's statment saying that 32-bit Windows couldn't assign more than 2GB address space to a process.

[cluberti]

How did I miss that? If I misquoted, I apologize.

Actually, XP can use the /PAE switch to enable page files larger than 4GB, but it won't allow physical memory over 4GB to be accessed. So it works, sort of .

[nmX.Memnoch]

No worries.

I wasn't aware of that XP actually does support the /PAE switch for larger page files. Although, if one needs more than a 4GB page file I'd say it's time to move to 64-bit and some more RAM.

[cluberti]

True