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Hi guys

 

Please can this topic be finally cleared up?

 

In PLAIN ENGLISH, what exactly is virtual memory and when/how is it used?

 

please can someone explain to me how to understand it and to change my settings.

 

some ppl tell me set it to 3 times the amount of RAM you got, then once i heard Greg say to set it to about 1024k. so whats the score?

 

Here is my settup (i have 1 gig ddr ram btw and Y drive is a spare hard drive i've got):

 

filepush.asp?file=virtual.jpg

 

is that ok? if not what and why should it be? and what do the other options mean?

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My virtual memory has the folowing settings:

 

filepush.asp?file=virtgeheugen.jpg

 

Why? Because I had a scene with a very big shadow mapped light in it (size was about 2000)MAX was gicing me a hard time rendering with that large shadow map; I got errors etc.. And it basically wouldn't render. After I set my virtual memory to high amounts like above, the scene rendered again..

So that is what virtual memory does to me... ;)

 

My physical memory is 512MB

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Strat,

 

Do you have any problems with your setup?

 

Whats the reason for the sudden topic revival? The reason I ask, is cause this topic has never been resolved. The debate still rages on on hundreds of forums...depending on who you talk to, will result in completely different answers.

 

I set the min/max to the same size to prevent fragmentation of the drive the swap file is on. If you let windows manage the size of the swap file, the drive becomes fragmented faster, resulting in a loss of disk IO performance. If you ever need more virtual memory, just increase the min/max numbers.

 

Here's a quick definition...

 

pagefile

 

In storage, a pagefile is a reserved portion of a hard disk that is used as an extension of random access memory (RAM) for data in RAM that hasn't been used recently. A pagefile can be read from the hard disk as one contiguous chunk of data and thus faster than re-reading data from many different original locations. Windows NT administrators or users can reset the system-provided default size value of the pagefile to meet their particular needs.

 

And here's an article...

 

http://www.arstechnica.com/tweak/nt/pagefile-1.html

 

Its a bit old, but it still helps explain some things. If you want more current data, so some websearchs on pagefile, virtualmemory. Also check the hardocp, 2cpu.com, anandtech, and cgtalk forums.

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Originally posted by Greg Hess:

Strat,

 

Do you have any problems with your setup?

 

Whats the reason for the sudden topic revival? The reason I ask, is cause this topic has never been resolved. The debate still rages on on hundreds of forums...depending on who you talk to, will result in completely different answers.

 

cheers for that Greg.

 

Reason i ask is because im setting up my new pc ( a xeon 2.6, 1 gig ram) and i just wanted finally to understand what virtual memory is and how to manage/use it.

 

and no, i dont have a problem with the 1024 settings you once suggested. they seem to be fine :) i was just wondering what tweeks i may make to fine tune things.

 

ok, so ppl still debate it and bang on with their own ideas? thats fine by me, i just thought there'd be a definate black or white answer. looks like not.

 

thanks again Greg. um....same as before, clear as mud....but it's working fine so i'll leave it there and accept it. :)

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thanks again Greg. um....same as before, clear as mud....but it's working fine so i'll leave it there and accept it. :)

 

The truth is, I don't even think microsoft knows how the damn thing works. I sure as heck don't. I just know after four or so years of setting up systems, that just setting max and min to the same size, on the system partion, seems to help stabilize and prevent system fragmentation.

 

Realistically? Optimizing the pagefile will probably result in a 1% change in performance, the bottleneck isn't the drive, its the system ram. Run out of ram, and you know what happens :) .

 

There are however a lot of Windows XP tweaks you can use to speed up the system. (You have to use Windows XP SP1 or Windows 2000 Server with a Dual Xeon system to make use of hyperthreading). If your interested in those, I'll try and write up a little blurb about them when I have a second.

 

If you really want to see clear as mud...try understanding the new opteron naming scheme. I just gave up. Its so $#@)(*&@! confusing. Damn AMD.

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Originally posted by Brian Cassil:

I for one would be very interested in that Greg.

I'll try to get something up tommorow brian.

 

I'll try to do this another day. I'm too tired :) .

 

Just set everything to classic mode, disable all effects cept truetype font, and under performance in ctrlpanel/system/performance set all to performance or off.

 

[ March 20, 2003, 05:50 PM: Message edited by: Greg Hess ]

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I set the min/max to the same size to prevent fragmentation of the drive the swap file is on
A friend (working at compac, next hp) told me the same thing... I did the same ever since... using the maximum of 4095 for swap files ;) yiha!

 

nisus

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  • 2 years later...

OK, I guess time to revive this thread. though all info was absorbed in this and previous threads I figured I'd bring it up again because we all probably have upgraded since. I for one now run Dual Xeon 3.2G with 2 gigs RAM multiple drives, etc. etc. I played with my pagefile now MAX seems to be running slower than it did with my P3 500 I had in 98! Render dialog indicates I'm using 328 megs of Phisical RAM and 342 of virtual RAM How can this make sense? What should I do as far as my system drive in regards to pagefile size and my additional drive? From what I've read I should make the pagefile on C drive 2megs Min and Max and 2 gigs min and max on my storage drive? Anyone with suggestions, I'd appreciate it. Thanks.

-=Rob

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I was going to start a new thread, but searched and found this one. Hopefully it won't get ignored for being so old.

 

I have a machine that just sits there most of the time, most useful for printing, scanning and distributed rendering. Its an Athlon2400+ w/ 1.5GB RAM. The thing had been using W2K upgraded from NT4. But the DR rendering apps often crash, so I reluctantly upgraded the OS to XP-Pro yesterday.

 

The install went without incident, except once it booted into the new XP-SP2 the machine beeps and says there isn't a paging file, I should set one up. So I do, it re-boots, says there is no paging file. The screen shows my C: drive with the settings, but below says allocated = 0 MB I've changed it a few times to different numbers, tried 'system manage' but each bootup is the same 'problem creating paging file, go set one up'.

 

Any ideas on how to solve this?

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