As I have been researching mods for my new game of Oblivion I have noticed an interesting (to me) fact about the use of BSAs. There is absolutely no consistency about their use. I have one mod with a BSA below 100 kb in size and another mod with over 500 MB of files with no BSA. This seems rather illogical to me. I have read that you want to be careful not to exceed somewhere between 300 - 400 total (somewhat indefinite -any better guidance?) ESPs, ESMs and BSAs in your Data folder to prevent problems. I have also read threads discussing the benefits of placing BSAs on different drives and the fact they can not be larger than 2 GB. But what to do about the thousands of loose files in the various folders in the Data folder and the large number of very small BSAs counting against your 300 - 400 limit? Is there any consensus about how to manage these items? Should I pack all the loose files into just - under 2 GB BSAs and link them to one of the ESPs? I believe I read a statement by Arthmoor that he did something similar to this but I can not remember the exact context of the discussion. Should I unpack the small BSAs and add them to the large BSAs? Are there any issues with doing any of this that I should be aware of? Any information on this topic that has been proven to be of benefit to performance (the holy grail of my research) would be much appreciated.

You can repack BSAs if you want. That 300-400 cap is not going to become anymore definite because systems vary. That's it.

http://sites.google.com/site/oblivionpoinfo/intro/archiveinvalidation


What is faster?

• load BSAs through INI registration <-- have to worry about regenerating the INI and TESCS uses a separate INI
  
• use striping <-- advanced, look into this topic, not Oblivion specific, must use INI registration method to use this
  
• pack loose data files into BSA with "no compression" level <-- if you have copies of files already in BSAs you should unpack those BSAs first to avoid duplicates
  
• do not have multiple copies of data files in different BSAs (if it is not too tedious) <-- goes off the above
  
• PyFFI-optimize meshes before packing them into BSAs <-- general optimization, and usually decreases file size

Personally I don't see the point in BSA if they are smaller than about 25 MB.
For my own game I'm currently setting up, I install the mods with BAIN first, with all files loose in the Data folder. Keeping them loose this way makes it easier to spot conflicts with mods using the same resources. When I have installed all the mods I'm going to use, and after having Merged all the mergeable ones, then I start making BSAs, the number depending on how many I can have before reaching the 375 (+/- 25) limit of ESMs, ESPs and BSAs that can reside in the Data folder before weird and not so wonderful things start to happen (or file thrashing as Wrye more bluntly put it).
Which ones are BSA worthy is determined by a strict screening process. The best candidates are those that contain lots of files and are confined to specific areas, like Elseweyr - Deserts of Anequina, Barthom, Windfall and the CNRP mods. Unfortunately in CNRP some Meshes or Textures will turn up invisble if they lack ...uh...mip maps? bipp maps? normal maps?...something, so those files need to be "loose" to work.

It is very, very important that you install everything in the correct order before doing this because that is a lot of content to unpack and go through if you make an installation mistake. Check out your setup thoroughly, in game too, before packing everything up. Use Reset BSA Timestamps afterward as well. If you want more control of the BSA timestamps, to get them to load in a specific order, you should get a file redater app.

Edit: If you do not go the INI-registration route, you can actually load all BSAs with the same plugin.

Edit: It seems that BSAs are loaded in alphabetical order when they share the same timestamp, so keep that in mind as well. Chances are you will have duplicates among some BSAs if you stay away from unpacking the BSAs for large quest mods and overhauls, so the load order of the BSAs could be relevant.

One advantage of BSAs is they can be reqistered in the oblivion.ini and loaded from another HD. Especially useful if you have fast raptors or SSDs!
I have all my modified textures and pyfii'd meshes, plus by biggest bsa files from several mods (all natural, Frans, artifacts) loading from my ini from a separate HD. Helps with keeping load times down.
But as Tomlong says, it is fraught with problems, if not done properly.

I thank each of you for your replies. After I finish deciding on the mods for my game I will definitely spend some time looking at all the mod BSAs and redoing, as necessary. A number of the small ones will be unpacked and the larger mods will have BSAs created. For instance, I just PyFFIed the meshes in "Reaper's Coldstone Town" and there are 1.5 GB of Meshes, Sound and Textures files in this mod. That certainly seems to fit the bill for a BSA confined to a specific area. I also believe that since this is my first time doing this drill I will stick to just making BSAs of large mods instead of trying to combine files from many mods. If it goes well next time I will be more daring. I may also try loading BSAs onto more than one drive as my Oblivion game is loaded on a WD Velociraptor and I have a third drive, a WD Black 2 TB that Maximum PC magazine rated as being nearly as fast as the Velociraptor. Hopefully, that would improve performance a little bit. Thanks again!

Oops, almost forgot. Tomlong, on your site (which I should visit every day as it is expanding and improving every day) I was a little confused about one part of your description of BSA naming. Coldstone is a perfect example. If I make a BSA of the Coldstone files and the ESP is called "Reaper's Coldstone Town.esp" do I name the BSA the same, including the spaces? Or should I rename the ESP to eliminate the spaces? I thought you were saying there shouldn't be any spaces in the BSA name but lower in your tutorial it listed Martigens Monster Mod with spaces. Mea Culpa if I just didn't read it correctly.

I was saying that there should not be spaces in the plugin's name, not the BSA's name. I will quickly review that page for any inconsistencies. Thank you for bringing this to my attention. Also, you cannot use the plugin loading method if you are planning on using striping. However, you can use plugins to load the BSAs in the data folder and use the INI to load BSAs that are not in the data folder. You do not have to use one method or the other. That might be helpful if you just want to try out the other method.

Edit: I am not sure whether or not I found the inconsistency that troubled you. Could you quote it here if the unclear line is still there, please?

Spaces in plugin names is perfectly valid. I've got plenty of those. Possibly only an issue if you want a BSA to go with it.

Whoever is packaging BSAs that don't amount to a hill of beans should really stop doing that. Causing the game to exceed the Data folder file limit is no fun, especially if the BSA turns out to have something silly like a SINGLE file in it (yes, this happened recently).

As far as what I did with my BSAs, if you look at the list of stuff in my load order page on Tomlong's site, all of the graphic enhancers listed there have been combined with things like the UOP and the vanilla files into uncompressed BSA files. I dislike leaving too much stuff floating loose in the Data folder, other than what I have to leave that way for CS use, and those mods that are really too small to justify it.

How to get it done without thinking too much: if you have DLCShiveringIsles, rename all BSAs you are trying to load "DLCShiveringIsles - .bsa". If you do not have SI, make a dummy plugin and call is something simple (i.e., Oblivion.esp) and rename all BSAs that need to be loaded "Oblivion - .bsa". BOSS already supports "Oblivion.esp" as dummy plugin too, no need to sort it yourself.

Edit: Another reason NOT to rename mod's plugins, which you should not have to do anyway, is because BOSS will no longer recognize it and be able to sort the plugin for you.

Hey, guys, this brought up a question in my head: how do you install a mod's data in BSA format, and is it possible to do it with a mod currently activated in your current savegame? It would really clear up space in my Data folder if I made OOO's files into one big BSA file.

Use http://www.tesnexus.com/downloads/file.php?id=8489 to pack up OOO's resources into a BSA. Afterward, unistall OOO, and reinstall only the plugins and the BSA.

Edit: Your statement sounded kind of awkward. BSAs are simply another archive format, albeit a very special format. You have to pack files into BSAs, just as you have to pack files into any other type of archive (.rar, .7z, etc.) It is not magic or some technologically advanced procedure.

Tomlong and Arthmoor: I did not express myself clearly enough and confused you both. First, you are absolutely correct, Tomlong, that you would not want to change the ESP name as it would not be recognized by BOSS. And, I also have many mods that have spaces in the ESP's names. But the following two sections from the tutorial confused me (last line in each):

1. Plugin Association Loading

* Rename the BSA to ".bsa"
o The plugin must be an ESP file.
o The "PluginName" does not include the ".ESP" extension.
o "Anything" must start with a space, if the BSAs name is not one word. (See examples below.)
* The plugin's name cannot contain spaces (except at the end.)

2. Won't Load BSA

* "": "Oblivion - AAA.bsa" "Example 1.bsa"
* "": "Example 4.bsa"

My example, the Coldstone mod, has an ESP named "Reaper's Coldstone Town.esp." Arthmoor, your statement "Possibly only an issue if you want a BSA to go with it" is my concern and question; what should be the BSA's name?

The Reaper....esp (an example of a "") will not load a BSA because it has spaces in the name. However, "Better Cities .esp" can be used to load BSAs that start with "Better Cities ". Just stick to using plugin names without spaces. Do you still find those two lines confusing?

Edit: I cleaned up the examples. Hopefully, that helps.

Actually, yes, "Reaper's Coldstone Town.esp" will load a BSA that fits the same name. In the game at least. I can tell you firsthand it works because I played around in the mod at one point with the BSA matching the ESPs name.

The CS though often needs coaxing to load the resources when spaces are in the names. I very often find that if I'm loading something like that into the CS the ESP+BSA both need no space in the names, or the BSA needs to be registered in the CS ini file. Manually unpacking the resources works too, but if you're going to do that, it's obviously best to let BAIN handle it.

Okay, so a plugin with spaces in the name can load a BSA as long as the BSA matches the name exactly?

Edit: ...I already knew that. I must have been really tired last night because...



Edit: I think I have finally sorted this out. If a plugin has spaces in the middle of the name, it can only load one BSA (a BSA that matches its name exactly) unless there is a space at the end. Then, the BSA can load any BSA that starts with its entire name, including the space (i.e., "Better Cities .esp" loads "Better Cities - .bsa".

Thank you Arthmoor and Tomlong for the advice and guidance. I believe I am OK now on BSAs (famous last words).

Stay tuned for another episode of "The Novice's Quest for Esoteric Oblivion Knowledge." Coming soon to a computer near you!