.BSA Files, should I use them? & Game performance?

[MotokoKHammond]

So the game by default uses it's vanilla assets in .BSA files, and I have herd some all be it inconsistent talk about people saying the game handles .BSA files faster and more reliably then "Loose Files". SO it got me thinking, could one take the mod's they have downloaded, and convert the loose files contained within and convert them into .BSA Archives. And if someone was to do so, would there be any tangible performance gains?

Edited September 14, 2020 by MotokoKHammond

[Mebantiza]

Yes, you could convert all your existing loose format mods to BSA's, but that does not necessarily mean you should. While BSA is ideal for large complex mods with custom assets, an 'all-bsa' load order might not end up looking the way the same way in game as the LO does with a mix of loose and BSA. YMMV. I suppose if one has a small, and not terribly complex LO, it could be done with few issues sure, but the larger the LO, things can get complex quickly.

 

As for 'performance', I have heard claims going back to Skyrim Classic days that there is, allegedly, a very modest gain to be had. However, I have not heard, to this day, from any reputable source, that bsa's do in fact, offer tangible performance benefits in game. AFAIK, no one has ever tested this theory in a serious way, which is probably why so much you see on the topic is conjecture.

 

That said, BSA, obviously do offer benefits, important ones or else they wouldn't exist or be Beth's default archive format. The question of "Is performance (improved) BSA vs Loose, though, is afaik, not one that has been really addressed in a definitive way.

[MotokoKHammond]

Yes, you could convert all your existing loose format mods to BSA's, but that does not necessarily mean you should. While BSA is ideal for large complex mods with custom assets, an 'all-bsa' load order might not end up looking the way the same way in game as the LO does with a mix of loose and BSA. YMMV. I suppose if one has a small, and not terribly complex LO, it could be done with few issues sure, but the larger the LO, things can get complex quickly.

 

As for 'performance', I have heard claims going back to Skyrim Classic days that there is, allegedly, a very modest gain to be had. However, I have not heard, to this day, from any reputable source, that bsa's do in fact, offer tangible performance benefits in game. AFAIK, no one has ever tested this theory in a serious way, which is probably why so much you see on the topic is conjecture.

 

That said, BSA, obviously do offer benefits, important ones or else they wouldn't exist or be Beth's default archive format. The question of "Is performance (improved) BSA vs Loose, though, is afaik, not one that has been really addressed in a definitive way.

Quite an interesting reply, and yes I had the same thoughts as to most arguements I have come across being conjecture. However despite not being maybe a easily quantifiable improvement, one has to wonder as the game does as far as I know load BSA files before loose, could milaseconds be shaved off load times, and possibly improve load stability in the process? I was wondering that especially in mods like large creature packs, with monsters requiring spawns and spawn corruption being a real issue, could a . BSA Archive benefit such things? In that regard, could Texture or mesh replacer mods benefit for .BSA archives or would such things be better loose?

[Striker879]

I don't have any other than conjecture to offer either, but something Moto has said does raise a question for me ...

 

If it is true that the game loads BSAs before loose files, then in the case of replacer mods (body replacers, armor retextures etc) that would mean the game would load the vanilla asset from the BSA and then need to reload the loose file replacer asset. Could a test of loading only vanilla assets and then one loading replacer assets show a measurable difference? What sort of tool would be needed for the job?

[Mebantiza]

Stability? Wouldn't say so. Define stable in this context. Less random crashes with BSA's vs loose? Nothing like that in offing since data is data. Whether a file gets read from the BSA, or directly from the directory is not really going to make much difference in that regard.

 

I have 91 BSA files currently in my LO, and while they are doing their job just fine, I would never assume, or suggest those files are somehow more 'stable' than the mods that are all loose. I still get the odd random CTD, and Its fairly safe bet if all my ~220 ESP assets were all packed into BSAs, I doubt that things (like the odd random) CTD, would cease, or even decrease.

[MotokoKHammond]

I don't have any other than conjecture to offer either, but something Moto has said does raise a question for me ...

 

If it is true that the game loads BSAs before loose files, then in the case of replacer mods (body replacers, armor retextures etc) that would mean the game would load the vanilla asset from the BSA and then need to reload the loose file replacer asset. Could a test of loading only vanilla assets and then one loading replacer assets show a measurable difference? What sort of tool would be needed for the job?

Well this is based upon what I have been told by quite a few people. Obviously I have no real proof of this, I am not a programmer myself and can monitor how and when the game draws its assets and where from it is drawing said assets. However myself and others would assume .BSA archives loading first is the reasson for Achive Invalidation no? If I am mistaken, please correct me. If there is no tangeable or monitorable benefit to .BSA archives whether it be space, stability, random read acess speeds or load priority, then one has to wonder why Bethesda is so fond of using them in the first place, as it is not like it is some encrypted proprietary format or anything.

[Mebantiza]

There are benefits, but talking strictly about in game performance' and BSA, as I said, Its not entirely clear on that question and hard data not easy to reference. For example, BSAs are terrific for installing and un-installing very large mods in the multi-gigabyte range. Losse files, take forever so BSA wins in that regard easily. While that is a huge benefit, it is not the same thing as, are they making my game faster and or more 'stable'? The install time is only one benefit of the BSA, there are others of course.

 

This is about I can find for videos on the matter. But, be aware, his test is limited *only* to game initial load time and only for F4. Interesting results, but a very limited test all the same.

 

[DrakeTheDragon]

Quite late to the party, but there's one other quite important point I haven't seen mentioned, yet.

 

Under original conditions the game knows no load order when it comes to BSAs. The order in which they're loaded is said to be erratic at best. Thus the replacer-type mods asked about won't even reliably work anymore, when served in BSAs. A BSA cannot override contents from another BSA. It was even an unwritten rule back then that a BSA of your own doing must not even contain the same files as another or Vanilla BSA.

 

However, with the introduction of some OBSE-loaded framework, bringing BSA handling up to speed with how it's done in the newer games, this is said to be no longer a problem. BSAs can override contents from other BSAs in Skyrim et al, and with said mod it is said to be the same in Oblivion then, too.

 

 

But I for one think the main motivation for Bethesda to put all Vanilla assets in BSAs instead of having them as loose files was 1) order: no game of a comparable size I know does "not" use archives for that, and 2) mods: that you can (almost) completely erase your entire data folder and the game will just jump back to Vanilla state, is definitely a welcome thing when it comes to handling mods.

[KatsAwful]

To expand on Bethesda's intentions with BSAs, the original design for overwriting vanilla files was that newer files overwrite the older Bethesda files in the BSA. The DVD release would always be older than any mod, so any loose file will always overwrite. However, it quickly became apparent that this barely worked in any intended fashion, hence archive invalidation. This is especially important with newer digital releases that leave the file date of all the BSAs as the date they're downloaded. SkyBSA from DavidJCobb fixes this issue and makes Oblivion act more like Skyrim where any loose file that overwrites a file in a vanilla BSA will be used. The same mechanism works for BSAs now, so if you have SkyBSA you technically could package your textures into a BSAs, but as others have said it doesn't offer a ton of utility (BA2 archives are much more efficient so it'll affect things more). Oblivion's I/O situation is very inefficient, you'll have longer load times just from having more plugins or models to load in. I haven't noticed a drastic increase in load times when adding texture packs compared to plugins and LOD generation

Mod authors package things into BSAs so they don't have to deal with loose files

[Striker879]

I wonder about the difference between loading a BSA at game start (but does the game even load all the BSAs?) vs loading assets as they are called for to render on screen.

 

So an example of what I'm getting at ...

 

So Joes Cool Armor mod has unique meshes and unique textures for let's say two dozen different armors. If the textures (or maybe even meshes and textures) are packed into JoesCoolArmors.bsa does the game load all of that into memory when the game starts and JoesCoolArmors.esp is loaded? If instead the mod is distributed as loose files does the game load JoesCoolArmors.esp at game start and then only load the specific meshes and textures required to render the individual armor pieces as they are going to be rendered in game (so 23 armors not loaded but the one you took from the JoesCoolArmors chest and either put on or gave to a companion to wear gets loaded into memory and displayed on screen).

 

Subtle difference, maybe not important to people with ultra rigs, but it could have a difference for those on marginal setups.