Page File size?

Page 2 - Seeking answers? Join the AnandTech community: where nearly half-a-million members share solutions and discuss the latest tech.

Sunner

Elite Member
Oct 9, 1999
11,641
0
76
Originally posted by: KoolDrew
how would it hurt performance because it would not.

It would not perform as well as if it were on a seperate physical drive but it would still perform better then having it on the same partision as Windows (ussually C)

How do you figure?
 

Nothinman

Elite Member
Sep 14, 2001
30,672
0
0
It would not perform as well as if it were on a seperate physical drive but it would still perform better then having it on the same partision as Windows (ussually C)

Not really. Putting it on another partition will just increase seek times because every pagefile access will cause the disk to have to seek between partitions, if the pagefile were in the middle of the partition holding Windows the seek times would be lowered because the heads would have a shorter distance to go.

I feel that having it in it's own little partition cuts down on fragementation and that helps reliability for the filing system.

If your pagefile is being expanded and causing fragmentation you either need to turn up the minimum size or buy more memory and frankly the slowdown caused by fragmentation will be nothing compared to the slowdown caused by just needing to page in and out of the pagefile.

The page file usually bogarts a portion of the filing system that can never be recovered for other uses or moved.

So? Every OS does that, the only difference is with most unixes it's a whole partition instead of a big file in another partition.

It may not be a issue in fresh installs, but once you start layering on the service packs as the OS ages, then it improves long term reliability.

Pagefile location has no affect on reliability.

Sort of like installing the core OS and program files on seperate partitions... I don't think that the performance hit would be any were near as significant as the possible benifits.

For Windows there's virtually no benefit to doing that since Windows puts 1/3 of it's files into 'Program Files' anyway and you need to do a reinstall for just about everything to make sure all of the files and registry entries are put back. For unix it makes more sense because /usr can be mounted read-only for normal use or it can be NFS mounted from another server.
 

drag

Elite Member
Jul 4, 2002
8,708
0
0
Originally posted by: Nothinman
It would not perform as well as if it were on a seperate physical drive but it would still perform better then having it on the same partision as Windows (ussually C)

Not really. Putting it on another partition will just increase seek times because every pagefile access will cause the disk to have to seek between partitions, if the pagefile were in the middle of the partition holding Windows the seek times would be lowered because the heads would have a shorter distance to go.

I feel that having it in it's own little partition cuts down on fragementation and that helps reliability for the filing system.

If your pagefile is being expanded and causing fragmentation you either need to turn up the minimum size or buy more memory and frankly the slowdown caused by fragmentation will be nothing compared to the slowdown caused by just needing to page in and out of the pagefile.

I couldn't care less about the performance. You say first that the seek times would decrease performance, but the filing system fragmentation doesn't matter because it's so slow as to be pointless to even care about the performance drop, which is it?

My reasoning has little to nothing to do with speed. I would just need it for the odd time that I would actually use the page file for something stupid... say a run away proccess.
The page file usually bogarts a portion of the filing system that can never be recovered for other uses or moved.

So? Every OS does that, the only difference is with most unixes it's a whole partition instead of a big file in another partition.

Yes, so make it a seperate partition like every other OS. Just because it still a file, doesn't mean that I can't just stick a extra 2 gigs of harddrive space aside for a partition for it, or that I shouldn't.

The swap file is dynamicly sized to fit whatever your needs are, it gets bigger if you need it on one or two occasions, and parts of it just don't go back to being smaller...
It may not be a issue in fresh installs, but once you start layering on the service packs as the OS ages, then it improves long term reliability.

Pagefile location has no affect on reliability.

No But I figure fragmentation of OS files on a NTFS partition may have reliablity issues, if your unlucky. If you have to do a recovery or investigation of some system files what are the chances of fixing files if they are all in one spot vs spread all over the harddrive?

It's not like it's a BIG DEAL or anything. It's just something that may be a good idea. On a scale of 1 to 10 of "stuff that realy matters" I give this a important of 1.5.

I give the importance of a performance drop of a page file seek caused by a seperate partition for the swap file of about 1.3. So 1.5 > 1.3, so I stick it in a seperate partition.

Sort of like installing the core OS and program files on seperate partitions... I don't think that the performance hit would be any were near as significant as the possible benifits.

For Windows there's virtually no benefit to doing that since Windows puts 1/3 of it's files into 'Program Files' anyway and you need to do a reinstall for just about everything to make sure all of the files and registry entries are put back. For unix it makes more sense because /usr can be mounted read-only for normal use or it can be NFS mounted from another server.

I didn't say anything about Unix or Linux or whatever. I know that MS choices of directory system/monolythic registry/mixing files is @ss....

The only thing I am thinking of is reducing filing system fragmentation, and the obviously negative benifits that is has on a w2k OS. That's it.

If I can aviod reshuffling around system files during a defrag, I figure that's a good thing. That's the only thing that I was thinking about.

Now if taking extra steps to avoid or at least cut down on filing system fragmentation isn't worth even the meakest effort, then tell me why.

I know on filing systems that fragmentation is sometimes a GOOD thing. But I am not aware of anything but negative effects with w2k + ntfs or for that matter FAT32.
 

Nothinman

Elite Member
Sep 14, 2001
30,672
0
0
I couldn't care less about the performance. You say first that the seek times would decrease performance, but the filing system fragmentation doesn't matter because it's so slow as to be pointless to even care about the performance drop, which is it?

Fragmentation doesn't hurt performance as much as people think because most files are read into memory in page size chunks, that's why it's called demand paging. And I believe the most read-ahead Windows will do is like 64K so unless your files are broken up into less than 64K chunks and spread across the disk randomly you won't notice a big performance decrease. Audio and Video processing are probably the only things that stream data in large enough chunks to be noticably slowed down by fragmentation and also maybe bittorrent when you restart a download and it rechecks the checksum on the file.

The swap file is dynamicly sized to fit whatever your needs are, it gets bigger if you need it on one or two occasions, and parts of it just don't go back to being smaller...

It's only grown if you set the minimum size too small and the new extents are removed on reboot.

No But I figure fragmentation of OS files on a NTFS partition may have reliablity issues, if your unlucky. If you have to do a recovery or investigation of some system files what are the chances of fixing files if they are all in one spot vs spread all over the harddrive?

The only time fragmentation might have an affect on reliability is if a fragment is in a bad sector or something and eventually that bad sector will affect something whether it's fragmented or not.

I give the importance of a performance drop of a page file seek caused by a seperate partition for the swap file of about 1.3. So 1.5 > 1.3, so I stick it in a seperate partition.

If you have 1 pagefile seek the chances are you'll have more than one and they add up, a seek from one partition to another is magnitudes slower than one within the same partition.

If I can aviod reshuffling around system files during a defrag, I figure that's a good thing. That's the only thing that I was thinking about.

But it's irrelevant, for the most part system files are no different than data files except that they're probbaly already paged into and locked in memory. With recent versions of Windows you can even move the pagefile around while it's in use.

But I am not aware of anything but negative effects with w2k + ntfs or for that matter FAT32

That's why XP and above intentially fragment some boot files so that they can be loaded faster.
 

KoolDrew

Lifer
Jun 30, 2004
10,226
7
81
So are you sayinbg that you should alweaysd have just 1 partision for games, OS and all your files? Right now I have a games and apps partision then a windows partision, page file partision, and a storage partision for storing files.

Is that fine besides the fact that my paging file is on a seperate partision>
 

drag

Elite Member
Jul 4, 2002
8,708
0
0
Not sure. I never used Windows much, so mostly it's speculation.

When I setup my parent's computer I installed WinXP and setup a smaller OS partition, and a bigger partition for general files and such. I installed all big games and big programs to the second partition. I didn't worry about the swap any, and left that alone. I put 1gig of RAM into the OS, and since they don't multitask much, that should be more then enough for the forseeable future. They probably never even used the swap once so far, except for the normal paging in and out of main memory that WinXP does time to time for whatever reason.
 

Steve

Lifer
May 2, 2004
16,572
6
81
www.chicagopipeband.com
Originally posted by: drag
Therefore swap file is memory that is not real memory, which makes it pretend memory. However computer programmers don't like to say "pretend", they say "virtual", because it makes them sound all futuristic and intellegent.

Pretend Memory


Hire untrained school kids to man your staff, because I like being told that the swap file on my computer is "pretend memory." Being talked down to by crater-faced sales staff is a humbling experience, and the phrase "pretend memory" is awesome. It makes me want to pay you pretend money for the pretend advice I received from your staff with pretend technical knowledge.
 

Nothinman

Elite Member
Sep 14, 2001
30,672
0
0
So are you sayinbg that you should alweaysd have just 1 partision for games, OS and all your files?

No, I'm saying that you shouldn't try to seperate \Windows and \Program Files. Putting your data (and games if you like) on a different partition (preferably on a different drive) is smart because if you break the OS or just want to format and reinstall your data is safe.

Right now I have a games and apps partision then a windows partision, page file partision, and a storage partision for storing files.

It just doesn't make sense if those are all on the same physical drive, all you end up doing is creating additional administrative overhead when one of those partitions runs out of space. What happens when your games partition runs out of space? Do you break out PQMagic and resize to give it more space, do you install the next game to the Windows partition or do you remove stuff to make space?
 

KoolDrew

Lifer
Jun 30, 2004
10,226
7
81
No, I'm saying that you shouldn't try to seperate \Windows and \Program Files. Putting your data (and games if you like) on a different partition (preferably on a different drive) is smart because if you break the OS or just want to format and reinstall your data is safe.

So you say i should not try to seperate /Program Files? What do you mean by that. You mean dont make a seperate partision for apps and keep them on the windows partision or no?

What would be the best setup with partisions and stuff for best performance? IS this good

1. OS and page file
2. apps
3. Gmaes
4. Storage
 

Sunner

Elite Member
Oct 9, 1999
11,641
0
76
I tend to separate ProgramFiles and WINDIR, you can do that via a registry key, that way most anything that isn't hardcoded to go to C:\PRogram Files will land where you point it, this was a fair number of programs and games will actually survive a Windows reinstall.
I just make two partitions though, C: for Windows and D: for everything else.

Of course in my main computer, I have 3 harddrives, so I just make those separate partitons.
 

Nothinman

Elite Member
Sep 14, 2001
30,672
0
0
What would be the best setup with partisions and stuff for best performance? IS this good

Generally you want as few partitions as possible to reduce unnecessary seeks. I would only create one for Windows and one for my data. If you're afraid that putting all that into one filesystem will fragment to hell and make it slow get a defragmenter that you can schedule and don't worry about it.
 

KoolDrew

Lifer
Jun 30, 2004
10,226
7
81
Thanks for the help. so I will jsut set it up like this..

1. OS and page file
2. apps and games
3. Storage

I heard that FAT32 is faster then NTFS on smaller partisions so that is why I had 4 for os, apps, games and storage. All in FAT32 for faster performance and then NTFS for the storage partision.
 

Gamingphreek

Lifer
Mar 31, 2003
11,679
0
81
I didn't read all of the thread so i apologize if it has already been answered.

The rule of thumb is 2x the amount of system RAM, and to keep it static. Although there is one flaw with this being that as you get more ram you need less PageFile.

-Kevin
 

Spencer278

Diamond Member
Oct 11, 2002
3,637
0
0
Originally posted by: Nothinman
The rule of thumb is 2x the amount of system RAM, and to keep it static

Then you should have your thumbs looked at.

I never understood the idea that page file should be a multiply of the ram. Was there ever a techinical reason for that rule to be invented.
 

Nothinman

Elite Member
Sep 14, 2001
30,672
0
0
Was there ever a techinical reason for that rule to be invented.

When a unix system panics it will stuff a copy of the system state into the swap space and on reboot that image will be copied out of swap so that it can be used normally again, this was done because if the system panic's theres no way to know within the kernel what part died so writing to the filesystem is dangerous but swap will be overwritten on a reboot anyway so there's no data to be lost there.

As for Windows, who knows. Windows doesn't have any fears about writing to the filesystem on a BSOD so that's irrelevant.
 

CTho9305

Elite Member
Jul 26, 2000
9,214
1
81
Originally posted by: Nothinman
Was there ever a techinical reason for that rule to be invented.

When a unix system panics it will stuff a copy of the system state into the swap space and on reboot that image will be copied out of swap so that it can be used normally again, this was done because if the system panic's theres no way to know within the kernel what part died so writing to the filesystem is dangerous but swap will be overwritten on a reboot anyway so there's no data to be lost there.

As for Windows, who knows. Windows doesn't have any fears about writing to the filesystem on a BSOD so that's irrelevant.

I think some older unixes also allocated space in the swap file every time you allocated space in ram - so if a program used 1GB of ram, it would need 1GB in the swap file. Nowadays, that doesn't happen.
 

Nothinman

Elite Member
Sep 14, 2001
30,672
0
0
I think some older unixes also allocated space in the swap file every time you allocated space in ram - so if a program used 1GB of ram, it would need 1GB in the swap file. Nowadays, that doesn't happen.

Sort of like how Windows uses pagefile reservations, except with them the data isn't paged to disk until it's really necessary.
 

Basie

Senior member
Feb 11, 2001
634
0
71
Isnt page file size based also on how the computer is used? For instance, I have it set static 800MB. According to System Monitor I hardly ever use over 100MB with 512MB system ram. But, I use my computer for some games, surfing the web and working with OfficeXP. Users of Graphic Intensive Apps
Video Editing and Heavy Gaming would be Paging alot more and so the requirements would be greater.
Does that make any sense? I did setup a separate partition 1G for the page file which I found out later
is not as much of advantage as placing it on another hard drive.
 

Smilin

Diamond Member
Mar 4, 2002
7,357
0
0
Originally posted by: Nothinman
Was there ever a techinical reason for that rule to be invented.

When a unix system panics it will stuff a copy of the system state into the swap space and on reboot that image will be copied out of swap so that it can be used normally again, this was done because if the system panic's theres no way to know within the kernel what part died so writing to the filesystem is dangerous but swap will be overwritten on a reboot anyway so there's no data to be lost there.

As for Windows, who knows. Windows doesn't have any fears about writing to the filesystem on a BSOD so that's irrelevant.

Ah Nothingman, it's a rare occasion indeed that I'll catch you in a slipup I still got the love for ya.

Windows actually does the same thing. It shoves the contents of memory to the pagefile during a STOP. Your memory dump file is only generated during the next boot when pagefile.sys is copied to memory.dmp. Furthermore, it won't attempt this on a non system drive. That's why you must have at least the dumps worth of pagefile (same as physical memory for a full dump, about 400mb or so for a kernel) on your system drive to get a dump. You can have additional pagefile elsewhere as well as the final location for memory.dmp on a different drive if you wish.

If you have a filesystem related crash (Stop 0x0000007B, Stop 0x00000024 come to mind) then a memory.dmp may not be generated. Windows won't attempt to force the issue on a misbehaving filesystem. That makes for bad mojo.

As for the thread as a whole: People, under Windows XP just let the OS handle it. You'll get grey hairs on your head trying to out-clever the memory manager and you won't end up with a performance benefit. See one of the Bajillion (that's with a B) posts that have already been written on this topic. If you wish to get a full memory dump during a crash keep at least your physicals ram's worth (plus about 50mb) of pagefile on C:. Other than that there really isn't much to know. The 1.5x ram rule of thumb ain't bad but it's pretty obsolete.
 
Jun 11, 2004
150
0
0
Back to the original post that started this brawl, a 2MB minimum size is going to get expanded (and fragmented) shortly after Windows loads. Best to start larger, or just let Windows deal with it. Out of boredom I played around with the minimum setting on a 1GB system and found Windows complained until the minimum was set at 32MB or more.

I guess you can always monitor the commit charge to see what is going on, but that seems like a lot of work in this situation for no real reason. With 192MB of RAM, let the system deal with the problem. The 287MB max size here makes everything very tight.
 
sale-70-410-exam    | Exam-200-125-pdf    | we-sale-70-410-exam    | hot-sale-70-410-exam    | Latest-exam-700-603-Dumps    | Dumps-98-363-exams-date    | Certs-200-125-date    | Dumps-300-075-exams-date    | hot-sale-book-C8010-726-book    | Hot-Sale-200-310-Exam    | Exam-Description-200-310-dumps?    | hot-sale-book-200-125-book    | Latest-Updated-300-209-Exam    | Dumps-210-260-exams-date    | Download-200-125-Exam-PDF    | Exam-Description-300-101-dumps    | Certs-300-101-date    | Hot-Sale-300-075-Exam    | Latest-exam-200-125-Dumps    | Exam-Description-200-125-dumps    | Latest-Updated-300-075-Exam    | hot-sale-book-210-260-book    | Dumps-200-901-exams-date    | Certs-200-901-date    | Latest-exam-1Z0-062-Dumps    | Hot-Sale-1Z0-062-Exam    | Certs-CSSLP-date    | 100%-Pass-70-383-Exams    | Latest-JN0-360-real-exam-questions    | 100%-Pass-4A0-100-Real-Exam-Questions    | Dumps-300-135-exams-date    | Passed-200-105-Tech-Exams    | Latest-Updated-200-310-Exam    | Download-300-070-Exam-PDF    | Hot-Sale-JN0-360-Exam    | 100%-Pass-JN0-360-Exams    | 100%-Pass-JN0-360-Real-Exam-Questions    | Dumps-JN0-360-exams-date    | Exam-Description-1Z0-876-dumps    | Latest-exam-1Z0-876-Dumps    | Dumps-HPE0-Y53-exams-date    | 2017-Latest-HPE0-Y53-Exam    | 100%-Pass-HPE0-Y53-Real-Exam-Questions    | Pass-4A0-100-Exam    | Latest-4A0-100-Questions    | Dumps-98-365-exams-date    | 2017-Latest-98-365-Exam    | 100%-Pass-VCS-254-Exams    | 2017-Latest-VCS-273-Exam    | Dumps-200-355-exams-date    | 2017-Latest-300-320-Exam    | Pass-300-101-Exam    | 100%-Pass-300-115-Exams    |
http://www.portvapes.co.uk/    | http://www.portvapes.co.uk/    |