Virtual Memory Optimization Guide!

[Chai]

AFAIK, Photoshop uses its own paging file system.

[Adrian Wong]

skywalka, I think I answered those questions in the guide already.

Yeah, like Chai said, Photoshop uses its own virtual memory system.

[skywalka]

Originally Posted by Adrian Wong

skywalka, I think I answered those questions in the guide already.

I don't think U did.

[Adrian Wong]

Originally Posted by skywalka

I don't think U did.

Actually, I did.

Let's take a look...

Originally Posted by skywalka

I remember I once was using a program (maybe Adobe Photoshop?) & I received an error when starting it because I was not using a pagefile. Is that what this statement is referring 2? These days I am not using any programs that tell me I need 2 have a pagefile. So do some (or all) programs have pagefile requirements that R not openly divulged?

Covered in the guide.

Originally Posted by skywalka

Let's assume I had 1 million gigs of ram & I was using Windows XP. Apart from the memory dump requirements, would I still need a paging file?

Covered in the guide.

Originally Posted by skywalka

Am I correct in saying Windows will not do a memory dump if there is no pagefile?

Yes. If I'm not mistaken, it's covered in the guide too.

Originally Posted by skywalka

I moved my paging file to another physical harddrive after reading your guide. Windows reccomends 1534 MB for my system. This is on my D drive.

Using Diskeeper I got the following notification:
There is no paging file on your boot volume. Microsoft highly recommends that you have at least a small paging file on your boot volume. Y is that?

That's because if you have a small paging file on the boot volume, it allows Windows XP to use it if the second drive is busy. Covered in the guide as well, albeit not written directly as such.

Originally Posted by skywalka

I tried keeping my D drive's setting & changing my C drive setting to be managed by the system. After rebooting my page file was 1534 MB ON EACH harddrive! So I then tried setting my C drive to the 2 MB minimum but noticed that the total is displayed as 1534 MB not 1536 MB. The C drive 2 MB is not included.

That's because it shows the actual amount of virtual memory, not the size of the paging files.

Hope that helps you some!

[skywalka]

I compiled my list of questions as I read thru your guide so I'd B surprised if they were specifically answered in there. Because U know the answers perhaps U think the info is there in a clearcut form but maybe there is some ambiguity to them.

Originally Posted by skywalka

do some (or all) programs have pagefile requirements that R not openly divulged?

I got the impression that programs don't directly use the pagefile. Only that Windows sends the programs 2 the pagefile in case their data needs 2 B retrieved later.

Originally Posted by skywalka

Let's assume I had 1 million gigs of ram & I was using Windows XP. Apart from the memory dump requirements, would I still need a paging file?

I'm thinking no?

Originally Posted by skywalka

I tried keeping my D drive's setting & changing my C drive setting to be managed by the system. After rebooting my page file was 1534 MB ON EACH harddrive! So I then tried setting my C drive to the 2 MB minimum but noticed that the total is displayed as 1534 MB not 1536 MB. The C drive 2 MB is not included.

I have set the minimum & maximum sizes for these drives' paging files so isn't the amount of virtual memory the same size as the combined paging files? I'm using CacheMan 2 monitor (& log) the size of the paging file usage & it hasn't been larger than 250MB. Also, I've only just noticed that there is no pagefile.sys on my C drive at all when checking with Windows Explorer (set @ 2MB min & max).

And a new query: Will Windows do a large memory dump over 2 harddrives if neither pagefile on each drive is not large enough 2 hold it independently?

[Adrian Wong]

As mentioned in the guide, whether you have tons of memory or not, Windows XP will automatically page out pageable data, just in case you need to free up memory for something else.

Remember, no matter how much free memory you have, Windows XP will use up most of it for the disk cache. So, you will still end up with very little free memory, to speak of.

But please avoid creating hypothetical questions. I can only answer to the best of my knowledge, and that certainly does not include one million GB of memory.

By default, the pagefile.sys file is hidden. Did you set Explorer to reveal hidden files?

For your new query = Yes, it should be able to do so.

[skywalka]

Originally Posted by Adrian Wong

By default, the pagefile.sys file is hidden. Did you set Explorer to reveal hidden files?

Yes. I can see the other pagefile.sys file on my D drive.

[Adrian Wong]

Originally Posted by skywalka

Yes. I can see the other pagefile.sys file on my D drive.

Hmm.. I have never tried the 2MB minimum size. But it looks like unless Windows XP uses it, the pagefile.sys file isn't created.

When I find time, I will try it out on my own system.

[goingcommando]

Adrian - Great article on swap/page files. Really informative. I did have a question though. I noticed the section on "moving the pagefile to a separate partition" indicates that it won't increase performance because you're moving it from cylinder 0 to some arbitrary number. I'm guessing this is because you are assuming windows is installed on the C: drive and therefore the paging file would be there as well? The reason I ask is that in setting up my new system, I was planning on making a 2GB primary partition (FAT32) first to put my paging file on, (as well as my photoshop scratchdisk) and then installing windows on the D: drive (NTFS). I've been reading how some viruses look for c:\windows to install and this simple drive tactic solves that. Have you come across any problems with this? I can hide the C drive and use it for DOS utilities, paging files, and any other misc things I might need. Plus, if it becomes fragmented, defragging a 2GB partition would be much faster than the entire 250gb. Does my logic make sense?

Thanks!
-gc

[Adrian Wong]

Hello gc,

I don't think that "drive tactic" will thwart anything but the simplest of viruses. Current viruses definitely do not simply look for C:\Windows to infect the operating system.

If you want to protect against viruses, trust me when I say, don't waste your time with such measures. Load an antivirus software in the background so that it continuously monitors for viruses.. and keep it updated.

BTW, if you are going to use the 2GB partition merely for paging files and temporary files, you are unlikely to find the need to defrag it much.

Hope that helps you some!