virtual memory tell me about it.

herm0016

Diamond Member
Feb 26, 2005
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my dell 600m running xp pro is telling me i need more virtual memory. i dont really know what it is or why i need more or what to do to "clean it out?" hope someone can help. thanks.
i do use some large programs such as mathematica and matlab 7 and solid works, not sure if this matters or not, but i figured i would share it.
 

Zepper

Elite Member
May 1, 2001
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Virtual memory in windows is basically the swap file. Unless you set it otherwise, the swap file is dynamic - IOW, it is automatically adjusted by Win as needed. Perhaps you are running low on drive space on the partition where the swap file is located. It is a good idea to try to maintain at least 15% free space on all partions both so the swap file can expand as necessary and so that the defrag program can run properly. One solution might be to move the location of the swap file to another partition where there is more free space. There are plenty of guides to setting up virtual memory in XP properly around the Web - just search on "optimizing Windows XP virtual memory". That should get you more info than you could want.

.bh.

:moon:
 

herm0016

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Feb 26, 2005
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ah, ok it says: total paging file for all drives is 766 mb
min is 2 max is 1512 mb
 

Zepper

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May 1, 2001
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I believe it is best to have contiguous space for the swap file so perhaps defragging the partition where the swap file resides would help also.

.bh.
 

imported_bum

Golden Member
Jan 15, 2005
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Or adding more system RAM would prevent you from needing the pagefile as much anyway :).

How much do you have, btw?
 

michal1980

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Mar 7, 2003
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if your doing fea with solidworks. u might need more help.

my sig is wrong, my current pc is a athlong 64, with 1.5 gigs of ram, and it was running out of memory, both physical and swap.

for the swap. if you have more then one drive, move the swap to a different drive,
defrag drive 1. then move the swap back. also set it to a constant size, if your doing fea, about 3 gigs should be good.


when i'm doing fea, my 1.5 gigs of ram, also has a swap file that is about 2.5 or so gigs large.

if solidworks starts giving you problems complaining about memory, u might need to run the /3GB switch.
 

Vegito

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Oct 16, 1999
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matlab + windows = out of virtual memory error..

better run it in linux.. i have 4gb xp pro machines and matlab keep giving out of memory error.. its in their knowledge base.. you can try to pack before running some of your stuff.. it'll optimize its memory space..

i started to test matlab on linux 64bit using fedora with 12gb memory.. seems to run okay.. better than the windows machine..
 

Ronin13

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Aug 5, 2001
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Originally posted by: Zepper
I believe it is best to have contiguous space for the swap file so perhaps defragging the partition where the swap file resides would help also.
AFAIK, you cannot defrag the swapfile. If it is fragmented you will have to set it to 'No Paging File', defrag the drive and then set the swap/paging file to the size you want.

 

LatinJones

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Nov 30, 2004
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Minimum should not be set to 2. I think what happens there is that when you first boot windows, it only allocates 2mb of disk space for the pagefile. Then when more pagefile is needed is has to allocate more space, up to the maximum.

I usually set the minimum value=maximum value so that there a max pagefile always allocated. For me it's 1536 and 1536. I've heard this can increase performance but I'm not sure it that's true. Just keep it set to 1.5 to 2 times the amount of system ram.

You might try increasing the minimum size to the size of your system ram and see if that helps.
 

herm0016

Diamond Member
Feb 26, 2005
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thanks for all the info, i only have 512 of ram right now, i guess i should get some more. so from all this: i do not have another drive, thinking about getting one though.
matlab and windows dont get along.
i should defrag? im not sure what is partitioned on my drive, i have not done anything to it, its stock. how do i distinguish btw partitions, or find if i have any, and find out which one has my swap file?

michal1980: what do you mean "run the 3gb switch?"
 

homercles337

Diamond Member
Dec 29, 2004
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Originally posted by: forcesho
matlab + windows = out of virtual memory error..

better run it in linux.. i have 4gb xp pro machines and matlab keep giving out of memory error.. its in their knowledge base.. you can try to pack before running some of your stuff.. it'll optimize its memory space..

i started to test matlab on linux 64bit using fedora with 12gb memory.. seems to run okay.. better than the windows machine..


Wrong. Youre confusing internal matlab limitations with windows swap memory. BIG difference there d00d. I run matlab for hours on HUGE data sets. Do i try and allocate something like zeros(2^14)? Nope, because matlab breaks for obvious reasons.
 

Zepper

Elite Member
May 1, 2001
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if you have more than one drive letter for your hard drive then it is partitioned - if only one. then it is not partitioned unless the mfr put a hidden partition on there to hold a copy of the OS and other stuff.
. You can look under the storage manager to see whether there are any hidden partitions on there.

.bh.
 

michal1980

Diamond Member
Mar 7, 2003
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link, tells you how to set up a 3gb switch

what it lets windows to is allocate up to 3 gb of memory to a program.

my solidworks/cosmos fea would not run with out this because i kept getting an error saying that solid works needs xx mb of conitouns memory but can only get less then that.

never had a problem with it after.

some system stablity is comprimised using the full 3gb switch, but i think if you apply the userva = 2900 switch it runs very good.

its all on the link
 

dhoytw

Banned
Dec 10, 2004
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Originally posted by: Ronin13
Originally posted by: Zepper
I believe it is best to have contiguous space for the swap file so perhaps defragging the partition where the swap file resides would help also.
AFAIK, you cannot defrag the swapfile. If it is fragmented you will have to set it to 'No Paging File', defrag the drive and then set the swap/paging file to the size you want.


If you have a third party defragmentaion program ie..diskeeper, you can defrag anything you would like....including the swap file.
 

Vegito

Diamond Member
Oct 16, 1999
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Originally posted by: homercles337
Originally posted by: forcesho
matlab + windows = out of virtual memory error..

better run it in linux.. i have 4gb xp pro machines and matlab keep giving out of memory error.. its in their knowledge base.. you can try to pack before running some of your stuff.. it'll optimize its memory space..

i started to test matlab on linux 64bit using fedora with 12gb memory.. seems to run okay.. better than the windows machine..


Wrong. Youre confusing internal matlab limitations with windows swap memory. BIG difference there d00d. I run matlab for hours on HUGE data sets. Do i try and allocate something like zeros(2^14)? Nope, because matlab breaks for obvious reasons.

--

pack is a matlab command not windows command.. the matlab is maxx thats why when you run pack, most of the time it runs better.. i went from 2gb to 4gb and it still runs out of virtual memory, it did nothing for my matlab so its memory issue. I never said windows gave me out of memory error, I said matlab. Thats why I started to use 64bit linux with matlab, it allows me to run larger data set with less frequent out of memory error

http://www.gridtoday.com/04/1115/104270.html
 

michal1980

Diamond Member
Mar 7, 2003
8,019
43
91
Originally posted by: forcesho
Originally posted by: homercles337
Originally posted by: forcesho
matlab + windows = out of virtual memory error..

better run it in linux.. i have 4gb xp pro machines and matlab keep giving out of memory error.. its in their knowledge base.. you can try to pack before running some of your stuff.. it'll optimize its memory space..

i started to test matlab on linux 64bit using fedora with 12gb memory.. seems to run okay.. better than the windows machine..


Wrong. Youre confusing internal matlab limitations with windows swap memory. BIG difference there d00d. I run matlab for hours on HUGE data sets. Do i try and allocate something like zeros(2^14)? Nope, because matlab breaks for obvious reasons.

--

pack is a matlab command not windows command.. the matlab is maxx thats why when you run pack, most of the time it runs better.. i went from 2gb to 4gb and it still runs out of virtual memory, it did nothing for my matlab so its memory issue. I never said windows gave me out of memory error, I said matlab. Thats why I started to use 64bit linux with matlab, it allows me to run larger data set with less frequent out of memory error

http://www.gridtoday.com/04/1115/104270.html

did you guys try the 3gb switch?

theres is a heavy memory limiation with windows, even if you get 4 gbs of memory, because windows by default uses 2gb of ram/swap, for the system (it will page 2 gb of memory for just windows, which is why normally you disable the swap if you are not running any thing that requires ALOT of memory, it will rarely use the swap under normal conditions)

and then the other 2gb will be allocated for programs, if you need more then 2gb of ram/swap, you will run out.

my solid works anayslis, was crashing when i went from 1 gig to 1.5 and the error was the same not enough memory, looking at the system info, there was still about 500 megs of ram left, so i dug around and on a pro-e board i found the switch above,

by using it, you program can now use 3gb of ram, if this is enough, i don't know, but its free and might be just enoguh to get you over the hump