Virtual Memory Settings

What is the formula for determining what virtual memory settings to use? Thanks in advance...

Chris, in general, 2.5 times your physical memory. Fwiw, if you have a lot of memory, I've always just let Windows handle it, with no problems. 384 rambus here for reference. John "Chris Shearburn" <[email hidden]> wrote in message news:7kA79.183836$[email hidden]... > What is the formula for determining what virtual memory settings to use? > > Thanks in advance... > >

Chris Shearburn wrote: > > What is the formula for determining what virtual memory settings to use? > > Thanks in advance... Here we go again......one for the FAQ :-) Well, I usually try to figure out how much memory I could possibly need, ad libbing it, then multiply by 2, currently running at 1 gig of virtual memory with 384 MB of RAM, WinXP recommends 575 Will I ever need that much, probably not, but I have the HD space so I err on the side of caution Beers and cheers (uncle) Goy http://www.theuspits.com "A man is only as old as the woman he feels........" --Groucho Marx--

> What is the formula for determining what virtual memory settings to use? > Thanks in advance... Here we go again......one for the FAQ :-) Well, I usually try to figure out how much memory I could possibly need, ad libbing it, then multiply by 2, currently running at 1 gig of virtual memory with 384 MB of RAM, WinXP recommends 575 Will I ever need that much, probably not, but I have the HD space so I err on the side of caution Beers and cheers (uncle) Goy http://www.theuspits.com "A man is only as old as the woman he feels........" --Groucho Marx--

You can look at the Peak memory usage in the Task Manager. Just open up as many apps as you ever will. I'm having 512 mb ram, and I've never exceeded 380mb used memory. Hence I can disable virtual memory, by setting it to 0 mb for all disks. WinXP complains a little about not being able to do crashdumps of the memory, but I could care less... (I'll never ever examine the memory at a crash, promise... I'll just change the video driver ;-) The formula 2xRam is not valid theese days. It's from the old days, when memory was expensive :-) /Carl "Chris Shearburn" <[email hidden]> wrote in message news:7kA79.183836$[email hidden]... > What is the formula for determining what virtual memory settings to use? > > Thanks in advance... > >

If your looking for speed, change the Virtual memory paging file so it stores on a different physical hard disk, that way it reads from two disks simultaneously, instead of just the one. Or, just get some sort of Raid 5 SCSI setup.. :) James "Chris Shearburn" <[email hidden]> wrote in message news:7kA79.183836$[email hidden]... > What is the formula for determining what virtual memory settings to use? > > Thanks in advance... > >

example.. 384 (actual physical memory) x 1.5 = 576 (cache file size) set your min (initial) and max file size to the same number of 1.5 times your actual memory. that will create a 'static' cache file and slightly improve performance. the hardrive wont 'thrash' as much. On Sat, 17 Aug 2002 22:43:15 GMT, "Chris Shearburn" <[email hidden]> wrote: >What is the formula for determining what virtual memory settings to use? > >Thanks in advance...

By physical memory you mean RAM, right? twenty-four <[email hidden]> wrote in message news:[email hidden]...

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> > example.. 384 (actual physical memory) x 1.5 = 576 (cache file size) > > set your min (initial) and max file size to the same number of 1.5 > times your actual memory. that will create a 'static' cache file and > slightly improve performance. the hardrive wont 'thrash' as much. > > On Sat, 17 Aug 2002 22:43:15 GMT, "Chris Shearburn" > <[email hidden]> wrote: > > >What is the formula for determining what virtual memory settings to use? > > > >Thanks in advance... >

"Chris Shearburn" <[email hidden]> wrote in message news:a2V79.15593$IJ.2071@sccrnsc02... > By physical memory you mean RAM, right? >yes..that's my take. dh

yes. :) On Sun, 18 Aug 2002 22:17:42 GMT, "Chris Shearburn" <[email hidden]> wrote: >By physical memory you mean RAM, right?

also, you can increase the cache file by more than 1.5 times but your actual RAM will prevent windows from effectively using the extra size created. to my knowledge, windows (not even NT or XP) is able to do that. :[ On Sun, 18 Aug 2002 19:18:11 -0400, twenty-four <[email hidden]> wrote: >yes. :) > >On Sun, 18 Aug 2002 22:17:42 GMT, "Chris Shearburn" ><[email hidden]> wrote: > >>By physical memory you mean RAM, right?

Why would you want a cache-file that big? I mean swapping that amount data from the memory, would make the PC so slow... If you are a simracer and has >=384 RAM you need no swap cache. If you are editing wideos, and the diskcache is used, it will take forever to do whatever you are doing.... Just add more ram. "twenty-four" <[email hidden]> wrote in message news:[email hidden]...

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> > example.. 384 (actual physical memory) x 1.5 = 576 (cache file size) > > set your min (initial) and max file size to the same number of 1.5 > times your actual memory. that will create a 'static' cache file and > slightly improve performance. the hardrive wont 'thrash' as much. > > On Sat, 17 Aug 2002 22:43:15 GMT, "Chris Shearburn" > <[email hidden]> wrote: > > >What is the formula for determining what virtual memory settings to use? > > > >Thanks in advance... >

On Mon, 19 Aug 2002 07:06:27 +0200, "Carl Ribbegaardh" <[email hidden]> wrote: >Why would you want a cache-file that big? >I mean swapping that amount data from the memory, would make the PC so >slow... The entire swapfile isn't swapped back and forth to memory. Just the tiny portions that are needed. You are VERY wrong. >If you are a simracer and has >=384 RAM you need no swap cache. Incredibly bad advice, sir. I hope no one takes it. Have a better one.

There's a very good analysis of swap file (Win98/Millennium) usage here: www.aumha.org available by doing a site search on "swap file." Remember there's a difference between the Win9x line which uses a swap file and Windows XP which uses a pagefile system. Systems these days are using primarily 256 MB of RAM and above, and there is very little need to adjust what the operating system (especially Windows XP) sets up by itself. Check out the information in "Memory Management in Win98 and ME." -- Chris H. "rrevved" <[email hidden]> wrote in message news:[email hidden]... > On Mon, 19 Aug 2002 07:06:27 +0200, "Carl Ribbegaardh" <[email hidden]> wrote: > > >Why would you want a cache-file that big? > >I mean swapping that amount data from the memory, would make the PC so > >slow... > > The entire swapfile isn't swapped back and forth to memory. > Just the tiny portions that are needed. > > You are VERY wrong. > > >If you are a simracer and has >=384 RAM you need no swap cache. > > Incredibly bad advice, sir. I hope no one takes it. > > Have a better one. > > >

On Mon, 19 Aug 2002 12:50:54 GMT, "Chris H." <[email hidden]> wrote:

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>There's a very good analysis of swap file (Win98/Millennium) usage here: >www.aumha.org available by doing a site search on "swap file." Remember >there's a difference between the Win9x line which uses a swap file and >Windows XP which uses a pagefile system. Systems these days are using >primarily 256 MB of RAM and above, and there is very little need to adjust >what the operating system (especially Windows XP) sets up by itself. Check >out the information in "Memory Management in Win98 and ME." > >Chris H. >

That's really cool, Chris, but you're not trying to tell us, as Mr. Ribbegaardh did, that a 384MB user doesn't need a swapfile ... are you? Also, you don't agree with Mr. Ribbegaardh that having a large swapfile uses more RAM ... do you? I hope not. :)

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>"rrevved" <[email hidden]> wrote in message >news:[email hidden]... >> On Mon, 19 Aug 2002 07:06:27 +0200, "Carl Ribbegaardh" ><[email hidden]> wrote: >> >> >Why would you want a cache-file that big? >> >I mean swapping that amount data from the memory, would make the PC so >> >slow... >> >> The entire swapfile isn't swapped back and forth to memory. >> Just the tiny portions that are needed. >> >> You are VERY wrong. >> >> >If you are a simracer and has >=384 RAM you need no swap cache. >> >> Incredibly bad advice, sir. I hope no one takes it. >> >> Have a better one. >> >> >>

You misinterpret me. I'm suggesting that if you have 384Mb ram, and if you do work that requires you to use like 600Mb Ram, you need more ram. Comprende? The swap-file is used when the Ram cannot hold any more data. From the WinXP helpfiles: "rrevved" <[email hidden]> wrote in message news:[email hidden]... > On Mon, 19 Aug 2002 12:50:54 GMT, "Chris H." <[email hidden]>wrote:

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> > That's really cool, Chris, but you're not trying to tell us, > as Mr. Ribbegaardh did, that a 384MB user doesn't > need a swapfile ... are you? > > Also, you don't agree with Mr. Ribbegaardh that > having a large swapfile uses more RAM ... do you? > > I hope not. > > :)

You misinterpret me. I'm suggesting that if you have 384Mb ram, and if you do work that requires you to use like 600Mb Ram, you need more ram. Comprende? The swap-file is used when the Ram cannot hold any more data. From the WinXP helpfiles: ------------------------------------- virtual memory Temporary storage used by a computer to run programs that need more memory than it has. For example, programs could have access to 4 gigabytes of virtual memory on a computer's hard drive, even if the computer has only 32 megabytes of RAM. The program data that does not currently fit in the computer's memory is saved into paging files. ------------------------------------- As long as you use only ram for your applications, the PC will run smooth. When you run out of ram, like if you have 128 mb ram and run WinXP along with OutlookXP, then the PC is getting seriously slow. If you have 512 mb, I do, and you never reach over 380 MB allocated memory at an instance, then you do not need any virtual memory (aka swap-cache). The virtual memory is only used for freeing up ram when the ram is full. I hope this clears things out? /Carl

On Mon, 19 Aug 2002 17:39:03 +0200, "Carl Ribbegaardh" <[email hidden]> wrote:

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>You misinterpret me. >I'm suggesting that if you have 384Mb ram, and if you do work that requires >you to use like 600Mb Ram, you need more ram. Comprende? > >The swap-file is used when the Ram cannot hold any more data. >From the WinXP helpfiles: > >

...but that's not what you said, sir. You weren't referring to that at all. Since you snipped ALL of your prior embarrasing comments from your reply, let's review, shall we? You said: :From: "Carl Ribbegaardh" <[email hidden]> :Newsgroups: rec.autos.simulators :Subject: Re: Virtual Memory Settings :Date: Mon, 19 Aug 2002 07:06:27 +0200 : Message-ID: <ajpucl$1d34dq$[email hidden]> : :Why would you want a cache-file that big? :I mean swapping that amount data from the memory, would make the PC so :slow... You are stating that big swapfiles slow down PC's, and stating that swapfiles are swapped into memory in their entirety. That's bullshit, of course. Here's a tip for you. Look up the words 'paging', 'paging file', 'IBM 360', 'virtual memory' and 'thrash'. :If you are a simracer and has >=384 RAM you need no swap cache. You are stating that you need no swapfile if you have 384mb of RAM That, too, is more silliness. Real bad advice, sir. Comprende, Carl? Hey Carl, what would you say if I told you that I was on the development team that originally INVENTED the concept of virtual memory .. a.k.a. swapfiles? You wouldn't believe it would you, Carl-ster. Some advice: Quit while you're behind.

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> >"rrevved" <[email hidden]> wrote in message >news:[email hidden]... >> On Mon, 19 Aug 2002 12:50:54 GMT, "Chris H." <[email hidden]> >wrote: >> >> That's really cool, Chris, but you're not trying to tell us, >> as Mr. Ribbegaardh did, that a 384MB user doesn't >> need a swapfile ... are you? >> >> Also, you don't agree with Mr. Ribbegaardh that >> having a large swapfile uses more RAM ... do you? >> >> I hope not. >> >> :) > >

> Hey Carl, what would you say if I told you that I was on the > development team that originally INVENTED the concept of > virtual memory .. a.k.a. swapfiles? Then I'd be very impressed. What O/S were you developing? I'm sorry if I'm wrong. My experiences with my own PC is that all my programs is running stable with 0MB paging size for all drives. I'm using WinXP and 512 Mb Ram. I'm using it for simracing, occasional programming, websurfing and graphics editing with gimp. I've been running 400Mb fixed swap for years, but since XP there's an option to completely disable it. I will continue to run 0 virtual. :-) /Carl

On Mon, 19 Aug 2002 18:25:31 +0200, "Carl Ribbegaardh" <[email hidden]> wrote:

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>> Hey Carl, what would you say if I told you that I was on the >> development team that originally INVENTED the concept of >> virtual memory .. a.k.a. swapfiles? > >Then I'd be very impressed. >What O/S were you developing? >

I worked in labs at Palo Alto, Yorktown Heights, Kingston, Rochester, Menlo Park, and elsewhere, for IBM Corp. as a developer in various System 360/370, System/7, System/38, and AS/400 projects. Path length, parsing, queueing, design, error management. I also worked in technical marketing, and Systems Engineering. I'm retired after 30 years. >I'm sorry if I'm wrong. My experiences with my own PC is that all my >programs is running stable with 0MB paging size for all drives. >I'm using WinXP and 512 Mb Ram. That's great. >I'm using it for simracing, occasional programming, websurfing and graphics >editing with gimp. >I've been running 400Mb fixed swap for years, but since XP there's an option >to completely disable it. >I will continue to run 0 virtual. :-) Cool. > >/Carl >

On Mon, 19 Aug 2002 17:39:03 +0200, "Carl Ribbegaardh" <[email hidden]> wrote: >I'm suggesting that if you have 384Mb ram, and if you do work that requires >you to use like 600Mb Ram, you need more ram. Comprende? no matter how much memory you have, without a cache file windows will run 'slower'. even though you can disable it, the cache file is an inherent part of the operating system. windows is made to use a cache file. using a cache file frees up more RAM for your programs, games, NR2000, etc. also, windows uses the cache file to perform 'basic' operations like file management. again, no matter how much RAM you have, windows runs better with a cache file. >The swap-file is used when the Ram cannot hold any more data. >From the WinXP helpfiles: you are very wrong. you really shouldnt be giving advice on this matter.

you can 'completely' disable it in 95 and 98 too but that wont give you the best performance. On Mon, 19 Aug 2002 18:25:31 +0200, "Carl Ribbegaardh" <[email hidden]> wrote: >I've been running 400Mb fixed swap for years, but since XP there's an option >to completely disable it. >I will continue to run 0 virtual. :-) > >/Carl

Why would I want to free up memory by storing it onto the disk, when I have much more than 100Mb free ram? To me it's obvious that I'd want to use ram rather than disk, if there is ram memory left. Maybe I'm dead wrong here? I'm curious about the file-ops you talk about? That is something I'm not aware of. Could you point me to some current reference-litterature? I've been searching the MSDN but I cannot find the file-operations you mention. Again I'm sorry if I'm giving someone bad advices. That is something I do not want to do. /Carl

On Mon, 19 Aug 2002 18:52:14 +0200, "Carl Ribbegaardh" <[email hidden]> wrote: >Why would I want to free up memory by storing it onto the disk, when I have >much more than 100Mb free ram? >To me it's obvious that I'd want to use ram rather than disk, if there is >ram memory left. > Carl, do you monitor your system's memory/file paging needs every few microseconds? Windows does. >Maybe I'm dead wrong here? > Hey, it can work under some limited circumstances, but it is POOR advice that you're spreading around. >I'm curious about the file-ops you talk about? That is something I'm not >aware of. Could you point me to some current reference-litterature? I've >been searching the MSDN but I cannot find the file-operations you mention. > When a virtual-memory enabled operating system, such as Windows gets a file/record request, it automatically -assumes- that the file fragment is available in RAM. If it isn't, it issues a 'page-fault' and 'pages out' to the swapfile to find what it needs. If it is there it retrieves it. If not, it issues a disk read to disk controller(s), which in turn request the file open/fragment through the FAT system, and eventually to the physical file. It's cheaper, performance-wise, to use RAM, or the swapfile to get a data fragment ('page'), than to deal with the hardware and normal FAT file system of the computer. Your problem is that you have it in your head that the -entire- swapfile is brought into RAM. You stated that in your prior post. That's crap and I pointed that out to you in my earlier reply, but you are apparently oblivious to new knowledge. From your comments, you have no clue as to how a VM paging system (swapfile) works, and have decided to not use one. That's cool. Just don't post your misguided theories about VM here and not expect to be challenged on their voracity. >Again I'm sorry if I'm giving someone bad advices. That is something I do >not want to do. > Then learn more before recommending that people not use a swapfile. FYI, the largest/fastest systems in the world with incredible amounts of 'RAM' use Virtual Memory. All the time. >/Carl >

i run several programs (with large footprints) at the same time. the graphics program i use needs 200megs just to start up. i'm now using xp pro but win95/98 can only make use of maybe 192megs of RAM at best. i've been running my own pc repair/ web design service for over 9 years now and i know a little about this. please keep reading MSDN and, 'for now', please avoid giving technical computer advice. :\ On Mon, 19 Aug 2002 18:52:14 +0200, "Carl Ribbegaardh" <[email hidden]> wrote: >Why would I want to free up memory by storing it onto the disk, when I have >much more than 100Mb free ram?

exactly. even a pc with a gig of ram will be more stable and efficient with virtual memory turned on. turning off your VM is just plain bad advice. On Mon, 19 Aug 2002 12:10:49 -0500, rrevved <[email hidden]> wrote: >FYI, the largest/fastest systems in the world with incredible >amounts of 'RAM' use Virtual Memory.

> Carl, do you monitor your system's memory/file paging needs every > few microseconds? > > Windows does. There is imo no need for me to monitor it that often. Peak memory usage is easily read from the system ;-)

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> >Maybe I'm dead wrong here? > > > > Hey, it can work under some limited circumstances, but it is > POOR advice that you're spreading around. > > >I'm curious about the file-ops you talk about? That is something I'm not > >aware of. Could you point me to some current reference-litterature? I've > >been searching the MSDN but I cannot find the file-operations you

mention.

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> > > > When a virtual-memory enabled operating system, such as Windows > gets a file/record request, it automatically -assumes- that the file > fragment is available in RAM. If it isn't, it issues a 'page-fault' and > 'pages out' to the swapfile to find what it needs. If it is there it > retrieves it. If not, it issues a disk read to disk controller(s), which

in > turn request the file open/fragment through the FAT system, and > eventually to the physical file. Doesn't that imply that it has to be swapped out in the first place? If there is always 100-300mb ram avaliable, why wouldn't the fragment be in memory? If you are talking about a fileserver, I'm completely with you, but this is single user gameing-machines we talk about, with normally a maximum uptime of 10 hours. > It's cheaper, performance-wise, to use RAM, or the swapfile to > get a data fragment ('page'), than to deal with the hardware > and normal FAT file system of the computer. Of course the swapfile is positioned in the fastest sections of the disk, but Windows (Xp) does the same with all frequently used programs. > > Your problem is that you have it in your head that the -entire- > swapfile is brought into RAM. You stated that in your prior post. > That's crap and I pointed that out to you in my earlier reply, > but you are apparently oblivious to new knowledge. No, I do not think that. It was a misunderstanding, probably due to my bad english. I said: "Why would you want a cache-file that big? I mean swapping that amount data from the memory, would make the PC so slow... " With that I mean that if you fill up your memory, maybe with a huge bitmap or a wavefile, that is so big that it needs to be swapped out to disk, the PC will be a pain to work with. I do not mean that the swapfile is placed into ram, all at once. Obviously the disc-cache is used to put chunks of data to free ram. When the cached data is needed, the current ram needs to be cached to disk (if the ram is full), before the cached data can be moved to ram. > > From your comments, you have no clue as to how a VM paging > system (swapfile) works, and have decided to not use one. That's cool. > Just don't post your misguided theories about VM here and not > expect to be challenged on their voracity. > I think I was unclear in my statement. My bad. I've hope I've explained it better above?

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> >Again I'm sorry if I'm giving someone bad advices. That is something I do > >not want to do. > > > > Then learn more before recommending that people not > use a swapfile. > > FYI, the largest/fastest systems in the world with incredible > amounts of 'RAM' use Virtual Memory. > > All the time.

I do not doubt it, but it's not the same hardware as we are using. Neither the same apps.

On Mon, 19 Aug 2002 21:20:10 +0200, "Carl Ribbegaardh" <[email hidden]> wrote:

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>> Carl, do you monitor your system's memory/file paging needs every >> few microseconds? >> >> Windows does. > >There is imo no need for me to monitor it that often. Peak memory usage >is easily read from the system ;-) > >> >Maybe I'm dead wrong here? >> > >> >> Hey, it can work under some limited circumstances, but it is >> POOR advice that you're spreading around. >> >> >I'm curious about the file-ops you talk about? That is something I'm not >> >aware of. Could you point me to some current reference-litterature? I've >> >been searching the MSDN but I cannot find the file-operations you >mention. >> > >> >> When a virtual-memory enabled operating system, such as Windows >> gets a file/record request, it automatically -assumes- that the file >> fragment is available in RAM. If it isn't, it issues a 'page-fault' and >> 'pages out' to the swapfile to find what it needs. If it is there it >> retrieves it. If not, it issues a disk read to disk controller(s), which >in >> turn request the file open/fragment through the FAT system, and >> eventually to the physical file. > >Doesn't that imply that it has to be swapped out in the first place? >If there is always 100-300mb ram avaliable, why wouldn't the fragment be in >memory? >If you are talking about a fileserver, I'm completely with you, but this is >single user gameing-machines we talk about, with normally a maximum uptime >of 10 hours. > > >> It's cheaper, performance-wise, to use RAM, or the swapfile to >> get a data fragment ('page'), than to deal with the hardware >> and normal FAT file system of the computer. > >Of course the swapfile is positioned in the fastest sections of the disk, >but Windows (Xp) does the same with all frequently used programs. > >> >> Your problem is that you have it in your head that the -entire- >> swapfile is brought into RAM. You stated that in your prior post. >> That's crap and I pointed that out to you in my earlier reply, >> but you are apparently oblivious to new knowledge. > >No, I do not think that. It was a misunderstanding, probably due to my bad >english. >I said: >"Why would you want a cache-file that big? >I mean swapping that amount data from the memory, would make the PC so >slow... " > >With that I mean that if you fill up your memory, maybe with a huge bitmap >or a wavefile, that is so big that it needs to be swapped out to disk, the >PC will be a pain to work with. I do not mean that the swapfile is placed >into ram, all at once. Obviously the disc-cache is used to put chunks of >data to free ram. When the cached data is needed, the current ram needs to >be cached to disk (if the ram is full), before the cached data can be moved >to ram. > >> >> From your comments, you have no clue as to how a VM paging >> system (swapfile) works, and have decided to not use one. That's cool. >> Just don't post your misguided theories about VM here and not >> expect to be challenged on their voracity. >> > >I think I was unclear in my statement. >My bad. >I've hope I've explained it better above? > >> >Again I'm sorry if I'm giving someone bad advices. That is something I do >> >not want to do. >> > >> >> Then learn more before recommending that people not >> use a swapfile. >> >> FYI, the largest/fastest systems in the world with incredible >> amounts of 'RAM' use Virtual Memory. >> >> All the time. > >I do not doubt it, but it's not the same hardware as we are using. Neither >the same apps. >

Like I said, Carl, you are oblivious to actually learning anything about this subject. I'm through with you.

It might be to stupid to follow you here. Isn't it so that the memory is paged to disk, in order to free physical ram? If there is plenty avaliable physical ram, will it still page the memory? If so, why? If it is an algorithm that assumes my memory will be drained at some time, and frees up memory just in case, would that be beneficial? My expectation of my setup is that as long as I do not exceed 512mb allocated ram, my system will run pretty fast. If my o/s tries to allocate more than 512mb memory, I assume it will either grind down to a halt, or show a bsod. If I'm that far off, could you please point me to something I could read up on? It's not like I'm thinking you are wrong, I just want to know the facts regarding the VM. I guess I'm not seing the whole picture?

Correction from previous post: "It might be to stupid to follow you here." should read: "It might be I'm to stupid to follow you here."