Video Card RAM important?

[Sam DeathWalker]

Ok three possible storage areas:

1) Video Ram
2) System Ram
3) Hard Drive / SSD

You are saying that the game sets aside 128G (or some fixed figure) of video ram for its buffer and textures, per instance. Same with system ram it just sets aside a spicfic amount? What about casch hits, it dosnt look first to video and system ram to see if the texture is there (loaded as some old time in the past)? It just goes to the file in the wow folder it needs even if the data is in the system ram or the video ram? I see it would check but there is a fixed limit, if you are in a place where there are more textures then that limit it has to reload. And they set a limit cause of the 2G limit on 32bit apps. They must have upped the limit with the higher textures (4X more?) in WotLK.

Ya it won't store in vitrual memory.

Getting data, even from a SSD is way slower then getinng the texturs from system ram.

So it loads the zone textures (hence the small stutter when you enter a zone), some common textures and then if you see a new player or mob it goes to the wow folder to get that texture, without checking to see if that texture is already in system or video ram?

If you run two instances and the texture is already in video ram from one instance can the 2nd instance access that? I suppose not.

Overall that seems so inefficient....

You have any links where I can read about all this?


At any rate putting the wow folder in a system ram hard drive (makeing a hard drive out of system ram) is the way to go.

Well if that is all true then you are right if the game is not using the video ram (and it dosnt check to see if the data is already there) then 1G is more then enough.


OK the files are here:

WoW stores models as .M2 files, which is a WoW proprietary file format. It contains a lot of data such as bones, vertices, textures used, animations and more. These .M2 files are stored in compressed .MPQ files. The .MPQ files of interest are common.mpq, expansion.mpq and patch-x.mpq in the WoW\data directory

Ok its correct that over 1G is overkill:

http://www.evga.com/forums/tm.asp?m=...7&mpage=1&key=


This is why you only use single gpu with wow:

http://forums.wow-europe.com/thread....sid=1&pageNo=3

[Lax]

You are saying that the game sets aside 128G (or some fixed figure) of video ram for its buffer and textures, per instance. Same with system ram it just sets aside a spicfic amount? What about casch hits, it dosnt look first to video and system ram to see if the texture is there (loaded as some old time in the past)? It just goes to the file in the wow folder it needs even if the data is in the system ram or the video ram?

The game doesn't necessarily set aside a fixed figure. It is optimizing for minimal memory usage under any circumstance, to allow people with low end computers to play the game. It can't just assume it should be allowed to use up all of the available memory in order to speed certain tasks up. The textures loaded in memory "are" the cache, and they will be used from there as long as they are loaded. It does not need to go to the file in the WoW folder if it's already loaded (for any given window). It doesn't keep re-loading it from disk if it's still loaded, and it's loaded at least until it is no longer referenced by an active object, possibly longer depending on the game's optimizations. For example, when you enter an instance, most textures will no longer be used.

If you run two instances and the texture is already in video ram from one instance can the 2nd instance access that? I suppose not.

I briefly mentioned this in my first post: If a) you are running Vista or later, and b) the game is specifically designed to use shared textures, then the 2nd instance can re-use the same texture memory. I do not believe World of Warcraft is designed for this, and I do not know of any games off hand that are.

With 5 WoWs running at 1680x1050x32, I go from 966MB Texture Memory available to 831MB available at login screen, so about 27MB each just to launch (my estimate of backbuffer size seems to be off by a factor of 2), and I drop to around 550-590MB available in Wintergrasp attacking the keep with a few full raids in a massive lagfest, and roughly the same in Dalaran. So I could run 5 WoWs on a 512MB card and not run out of Video RAM even what would seem to be the most intense areas -- that's with WoW graphics settings all at the minimum for performance reasons. I just zoned into Gundrak, and my available Texture Memory went up to 770MB.

Texture Memory is a combination of all Video RAM on the video card handling the game instance, plus some System RAM set aside by the system architecture. Textures are loaded into whichever of those two areas that DirectX and the game determine is appropriate.

Getting data from ANY long-term storage device is, indeed, slower than retrieving it from RAM. That's why RAM is used for short-term needed data, and hard drives, SSD/flash, etc are used for long-term data A RAM drive would certainly be a great idea, if you've got enough RAM to mirror your entire WoW installation and still enough leftover to actually play the game. I've got 8GB free at the moment after running 5 WoWs but my WoW data folder is nearly 14GB. I'd need probably about 20GB of RAM to do that effectively, but I might try a few data files on a RAM drive to test what the actual effect is.

[Sam DeathWalker]

I'd need probably about 20GB of RAM to do that effectively, but I might try a few data files on a RAM drive to test what the actual effect is.

Sadly you cannot, all of wow has to be in the same folder ....

[Lax]

Actually I can, and so can anyone else that uses ISBoxer, by virtualizing the files.

[Otlecs]

For the record, you can use symbolic links (as distinct from junction points) on both files and folders in Windows to store files wherever you want. I'm always messing about with different setups to increase my perceived game peformance in my SSD / Raptor / regular stripe set configuration!

Thanks for the clarification on the technical details Lax - that's very interesting. It's also in line with what I would have expected just from critical thinking without any real knowledge to back it up, which is always nice

So for WoW at least, single GPU cards and "more" video memory are both Good Things, up to around 1GB after which it (arguably?) becomes wasted but not detremental.

Good stuff.

[Sam DeathWalker]

Ya I am really surprised as how its done, Ill bet they do the occlusion tests first before they even load the texturs. I.e. if someone is behind a wall right next to you they don't load that texture. They don't preload for people near you or anything it would seem. Not the way I would have designed it but I can see good reasons why they would do it this way as predicting who might come into your field of view is wastefull if that person dosn't.

This is easy to test just go to any crowed area and spin in place and see if you stutter.

So it would appear that the game very often is going for small packets of data from the wow data folder, on a continuous basis. Such info surely will let us optimize our hardware.

I see that my arguments in favor of Lax were not in vain.