What are HIBERFIL.SYS and PAGEFILE.SYS?

[MaSaM]

I searched about these files on the web and i was able to remove the hiberfil.sys as i never use hibernate!!...but pagefile.sys it seems that lots of warnings about removing it... why did these files just showed up in my drive few days ago while i had the same xp version installed for ages??

and is it true that slowdowns and lags may occur if i delet the file??

[Paul Komski]

If you dont use hibernation you can disable it in the APM settings and then delete the file from the drive to save space.

The pagefile (for virtual memory aka swap file) may or may not need access depending on your system and the amount of RAM you have installed. It is generally recommended to keep at least a small 2-4MB pagefile under Win2K/XP rather than have none at all - though I have been running WinXP with 1gig RAM and no page file quite OK for the past 6months or so.

Once again change the windows settings first before manually attempting to delete or otherwise manipulate the file.

Under WinXP:-
Start
RClick My Computer
Properties
Advanced
Settings
Advanced
Virtual Memory
Change
Highlight relevant drive
Organize Size
Set
OK
Reboot

You will have slowdowns related to available memory if you have small amounts of RAM and a small pagefile. This being accentuated if you have a very full hard drive.

[MaSaM]

I have 778Mb ram and as i usually check it on taskmanager (perfomance tab) i never reached a point to have a full RAM .....so i may narrow it down to 100mb instead of 1.1gb!!

[Paul Komski]

If you reduce the size rather than have no pagefile I think XP will, in any case, override you if it feels it necessary to expand its size.

[Sylvander]

In the event of a Windows crash....
Windows needs a pagefile on the Windows partition [C:?] at least as big as your RAM so that it can dump the contents of RAM in there for subsequent debugging.

I also recently discovered that my Adobe Photoshop program would NOT run unless it had some swap file on C:
Wouldn't run with only the swapfile on H:
So I added a big enough swapfile on C: too.

Previous to that I had a [just less than] 500 MB [fixed size] swapfile that almost filled a 500 MG Primary Partition [H:].
That makes sure that the paging file cannot become fragmented, which it did whilst on the C: partition.

[jlreich]

I also recently discovered that my Adobe Photoshop program would NOT run unless it had some swap file on C:
You should be able to go into Photoshop's preferences and change where it has it's swap file. You should be able to put it wherever you want it to be. In fact you should be able to setup several swap files if you like. In the case you run out of room in one place it will continue with the swap in the secondary position and so on.

Look for "Plug-Ins & Scratch Disks" in preferences. I have Photoshop 7, so whatever version you have may be slightly different.

[mjc]

The main thing is, that while Windows itself can exist without a pagefile (given adequate RAM) there are a number of programs that can't...most often, though, they will default to where ever you have set (or left at the default location) Windows pagefile to be...I never turn it off completely.

[Sylvander]

1. jlreich
How certain are you that it's the Scratch Disks preferences that specify where the Windows Swap/Paging file must be?
My Photoshop help files say...
"When your system does not have enough RAM to perform an operation, Adobe Photoshop uses a proprietary virtual memory technology, also called the scratch disks."
Surely this is saying Photoshop doesn't use the Windows Swap File, but its own proprietary swap file.
And what it refers to as "RAM", is I believe, what Windows calls "Memory", which is RAM plus paging file.
Isn't it the Memory and Image Cache settings that are important?

2. mjc
"most often, though, they will default to where ever you have set (or left at the default location) Windows pagefile to be...I never turn it off completely"
I had plenty [500 MB] of paging/swap file space allocated on its own dedicated [500 MB] H: partition, but Photoshop would complain about the lack of "RAM" unless I made a much smaller [200 MB] paging file on C: :(

[mjc]

That's why I said most...some programs, like PS can be a bit ornery.

[Sylvander]

Understood. :)

[jlreich]

1. jlreich
How certain are you that it's the Scratch Disks preferences that specify where the Windows Swap/Paging file must be?
I wasn't saying it controlled windows page file. Only it's own.

My daughter does very detailed very high definition artwork, I mean the kind of stuff that actually takes 30 min to an hour to render on a fast machine, and I have never heard a squeak out of Photoshop about not having a pagefile on C on any of the three machines I have it on. Although it's quite possible this is because they all have 2-4GB ram in them.

EDIT- on further thought I think you simply need more ram in your system. Photoshop does like lots of ram. I think it wasn't that you didn't have the pagefile on C, only that 500 wasn't enough pagefile, and adding the 200 made the difference no matter of where you put it.

[Sylvander]

1. "I think it wasn't that you didn't have the pagefile on C, only that 500 wasn't enough pagefile, and adding the 200 made the difference no matter of where you put it."
Seems not.
(a) After adding 200MB on C: to the 500MB on H: Photoshop worked again when it hadn't before.

(b) Then I increased the H: partition and its paging file to 1,000MB, and that made no difference [as expected].

(c) After reading your preceding post I reduced the paging file on C: to zero, expecting that after reboot Photoshop would still work [because the paging file had worked with 500+200 MB, and now it had 1,000 MB].
BUT NO...
It again said there was not enough RAM! :(

(d) So to make Photoshop work I'm going to be forced to yet again make a small paging file [256MB to match the RAM fitted] on C: so RAM can be dumped in event of a crash and there's enough space to take the dump.

[jlreich]

[256MB to match the RAM fitted]
Yep, that's your problem. Photoshop is one of those programs that likes as much ram as you can give it. By default it will use 50% of free physical ram. Half of whatever you have left from 256 after running windows isn't much at all to run Photoshop on.

After adding 200MB on C: to the 500MB on H: Photoshop worked again when it hadn't before.
Huh, I guess since I have been lucky enough to have at least 1GB ram on all my systems for the last five or six years and I have never came across this problem. :o

The only time it has complained is when I last rebuilt my daughters system and I forgot to change the scratch disk location from the default of C which was only 10GB and about 75% full. Changed it to a larger partition and never heard from it again.

[Sylvander]

"Yep, that's your problem. Photoshop is one of those programs that likes as much ram as you can give it"
Hmmm, I don't think so.
This version of Photoshop [5.0] has in the past worked with much less RAM than now.
The key decider seems to be whether or not there is ANY paging file on C:
If there is it works...
If there isn't, it doesn't.
Increasing the size of the paging file on H: from 500MB to 1,000MB failed to make it work...
Yet if I add a small paging file on C: that DOES make it work.

[jlreich]

I have never used v5. It's probably not as ram hungry as later versions. v7 doesn't care where the page file is.

Seems you have a handle on it. :)