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Free Space Requirement

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8 comments, last by Someone1 22 years, 6 months ago
You know how every game has a requirement for a certain amount of free space on the harddrive when attempting to run the game? Is that free space used for virtual memory? Sorry about my newbie question but I can''t seem to find the answer anywhere else. Thanks
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I have heard of games needing free space on the hard drive for installation , but that''s just so it can fit the game files.
I think the virtual memory is handled by the OS.
I believe the free space requirement is used for saving and loading games. Most of the old DOS games never listed any free space requirements because the ability to save games had no practical use when the game only lasted four hours or less.

Most Window and Mac games have the ability to save, load, and generate custom maps. Also the free space requirement is there to tell the user that to run the game smoothly, you need this much free space for background actions.

Also, virtual memory does not use the extra free space. VM uses only the space allocated by the user(you).
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quote: Original post by Amateur GP
I believe the free space requirement is used for saving and loading games. Most of the old DOS games never listed any free space requirements because the ability to save games had no practical use when the game only lasted four hours or less.

Most Window and Mac games have the ability to save, load, and generate custom maps. Also the free space requirement is there to tell the user that to run the game smoothly, you need this much free space for background actions.

Also, virtual memory does not use the extra free space. VM uses only the space allocated by the user(you).


The free space for example in the case of a game such as Anarchy Online is 1GB. There is no saving or custom maps or anything of that kind. All informaiton is saved on servers. So its not used for saving anything. Virtual Memory uses the space allocated by the user but that space is STILL space on the harddrive and unless you alter your settings (which the computer strongly recommends not to do it), there is no limit on how much virtual memory could be used up.

Another game is a game such as everquest which requires 200Mb of empty space on the harddrive before running the game. What are these empty spaces used for since they are not used for saving of any kind nor new maps or anything like that. The only thing you could do is take screenshots and you could only take about 10 which comes around 1 or so Mb. What would 200Mb be used for? Note that this is not 200 Mb to install. It takes 400Mb to install and another 200Mb free after installation just so it could run the game.

Games like everquest and anarchy online are massive-multi-player and have loads of things to put on memory. That is why it would make sense that such high amounts of free space be required to be used as virtual memory. While other games such as console games which are ported to the PC, don''t need any empty space to run because they are small, have few models and textures per level and therefore it''ll probably never exceed the Physical memory for virtual memory to be used.

That is why I think that since such high amounts of space are required for massive-multi-player games, that empty space requirement would have to be whats used for virtual memory.

Could someone please set me straight?


Thanks
perhaps the space is for temporarily decompressing stuff for the game... i.e. all the graphics are compressed into a huge ass file somewhere, but when the game is actually run it decompresses them for easy access.
i dunno, just [another] guess...

--- krez (krezisback@aol.com)
--- krez ([email="krez_AT_optonline_DOT_net"]krez_AT_optonline_DOT_net[/email])
quote: Original post by krez
perhaps the space is for temporarily decompressing stuff for the game... i.e. all the graphics are compressed into a huge ass file somewhere, but when the game is actually run it decompresses them for easy access.
i dunno, just [another] guess...


Hmmm that could be the case.

Thanks for the guess. So you are guessing that its all compressed and it needs to be decompressed when the game runs. I had personally guessed that its virtual memory usage. The above poster guessed its for saving data such as custom maps, saves, etc.

How could I find out which one it really is? Anyone happen to know exactly what that space is used for?

I don''t seem to be able to find a real answer anywhere.

Thanks again

I know Baldur''s Gate had a similar requirement. You needed 145MB free while playing the game. They mentioned that they did not like the way Windows ran the virtual memory, so they built their own virtual memory driver. I guess it is just a matter of a crazy idea that some developer has.

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quote: Original post by CaptainJester
I know Baldur''s Gate had a similar requirement. You needed 145MB free while playing the game. They mentioned that they did not like the way Windows ran the virtual memory, so they built their own virtual memory driver. I guess it is just a matter of a crazy idea that some developer has.


So that 145Mb was used for their own virtual memory driver they made? So for a game such as Everquest, which I am pretty sure did not make their own, that 200Mb is used for OS virtual memory?

I am pretty confused now.
MMORPGS commonly download updates/patches, so some space may be a temporary area for those downloads. They may download and cache some data from the server during a session, to reduce bandwidth requirements. Well-designed games might keep a session log for debugging use. The game might be autosaving for crash protection. I can think of hundreds of reasons to require free space, but the only way you''ll figure out what some specific game is using the space for is to ask the developer directly.
Many modern games use proprietary virtual memory managers. The Windows VMM is very inefficient when it comes to performance and wastes a lot of space for internal processing and management data. This may be required for general purpose virtual memory, but in a game (where you know exactly what parts of your VM are used for what data) performance can be greatly optimized by writing your own VMM.

In our current game, we gained over 1500% swapping performance with our own VMM, compared to the original Win2k system ! So it's definitely worth it.

Edit: and note that the Win2k VMM is very fast compared to the Win98 VMM ! Since lots of users still have Win98, with an extremely bad memory manager, compares will be even more in favor of your own system on this OS.

A.H aka Blueshift


Edited by - Blueshift on December 21, 2001 11:51:37 AM

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