Pagefile

[imported_Soepkip]

I am new to the forums here so my greetings to you all.

How come if i turn off my pagefile in win-xp and i go to task manager it still says pagefile usage 93mb?

Soepkip

 

[n0cmonkey]

Because a pagefile is pretty much required. Welcome to the forums.

 

[bobsmith1492]

My friend's computer has 1GB ram and mine has 512MB. How come mine uses less of the page file than his, and how come Windows doesn't want to keep everything in RAM when you have a ton of it? That is, what's so important about the pagefile that Windows always uses it and keeps about 100MB in it?

 

[oldman420]

windows has not really developed to the point that it will run entirely in ram effeciently. a page file is not used much if you have lots of ram and certian apps and games use a page file to operate. i let xp manage my pagefile as cheap as mass storage is i dont mind it at all.

 

[gsellis]

The pagefile is also used to store system information and settings in case of a crash. If a crash dump did occur, XP could then read the information for a dump report. If you turn on the full crash dump reporting, the pagefile MUST be larger than mem. If you use hibernate, the system will work better if the pagefile exceeds mem also.

Also, some memory spaced may get marked such that it would be written to the pagefile.

 

[Nothinman]

The Windows pagefile is used for more than just an extension of memory, it's required for some applications to run no matter how much physical memory you have. If you disable the pagefile Windows basically ignores you and creates a small one on the system drive for it's use.

And the PFUsage meter on task manager is a bad gauge, it's poorly labled and doesn't really mean just pagefile usage.

 

[Sianath]

Each running process has a limit to how much it can use. The memory manager manages this working set size (how much data is in physical memory) to keep one process from overrunning the entire system. Data will be paged out to file if it's not been accessed in a while to make room for more frequently accessed data.

For specific details, check out Inside Windows 2000, there's a 100+ page chapter devoted to just memory management.

Keep in mind that system data can be paged out as well, and you have no control over when that's done.

 

[bobsmith1492]

Well, basically, 'windows is wierd and just does stuff with the pagefile'

Oh well, as long as it works... thanks!

 

[imported_Soepkip]

I still dont get it.The way i understand now is that if i turn off the pagefile then i force programs and applications to use ram only but win-xp system data ignores it and still creates a pagefile wether or not i disabled it?

 

[n0cmonkey]

XP will use a pagefile no matter what you tell it.

If I'm not mistaken, a lot of the things that get paged out are things you aren't using.

 

[imported_Soepkip]

Ok its still a bit foggy for me but thanks for the replys

 

[drag]

Some programs are designed specificly to use the page file. They do it for performance reasons, I guess.

If the page file isn't there then they crash. So MS doesn't let you turn the file completely off because it will make bad things happen to your computer.


Sometimes programmers put some memory managment into their programs. For instance you may have some peice of data that you need to access it quickly, however you don't need it very often. So putting it into RAM would be bad because it would take up to much space and slow other things down, but eliminating it out of RAM would cause it to have to be read over from the disk, which is very slow. By sticking it in the page file it makes a good comprimise because it's faster then reading it from a file, but keeps the RAM cleared for more important things.

If the program is hard coded to do this and the page file is missing it will try to stick the peice of information in the file, but since the page file isn't their, then the program panics and simply crashes. It can't do it any other way.

 

[Nothinman]

Ok its still a bit foggy for me but thanks for the replys

No offense but that's why you shouldn't be questioning MS' requirement and usage of a pagefile, they've been developing a VM-based OS for years so they've had lots of time for trial and error.

 

[episodic]

The only nugget I'd give you is if you have 2 harddrives of the same speed, place the page file on the harddrive without the OS. That will allow for simaltaneous access.