How to find which mods affect fps the most?

[NemesysTrans]

Short of starting with an empty, new profile, is there any way to find which mods have a heavier toll on the framerate? I have quite a few mods enabled in my main profile and I started a plain one for the convoys. I was a bit surprised to see that I was dropping about 5 fps with all mods enabled. Ok, so, I know a lot of you will maybe laugh at it because 5 fps is nothing for your gear but I don't have many frames per second to spare on my laptop.

I'm guessing that some custom trucks might have a higher complexity than others in their 3D model but, other than that, what could affect the framerate? What about mods that put real companies skins on AI trailers? Or those that change the default gas station companies to real ones? Or one that add real truck physics?

Starting with a new empty profile and enabling every single mode one by one while checking the framerate might be a little tedious, so that's why I'm asking if there are other ways to have at least an idea of which mods might affect performance.

Thanks in advance for any suggestion!

[HagenXXV]

The more weight the mod has, the more resource it will consume on your computer, you should always look at the weight in megabytes of the mod.

[NemesysTrans]

Thanks @HagenXXV . That's a good starting tip!

[Wolfi]

The biggest issue is: unless you made the mod yourself, you can't really tell if it lags or not, because you can't be sure if it doesn't contain trash.
Assuming though your mods only contain what they have to:
Mods that don't place physical 3D objects in your game world should be ok. So physics/economy mods. (Those are usually fairly small in size as well, as technically they should only contain a bunch of text files.
Mods that place a physical object in your game world, so custom trucks, trailers, paintjobs, buildings, more traffic, etc will affect your frame rate if done incorrectly.
If such a mod is well optimized, it should be fine. But most of them are not. Also, the more things the mod changes/adds at a time, the more likely it is to have an impact. So a real company mod that changes a lot of trailers on the road and replaces logos on a lot of buildings can have a rather visible impact.
As Hagen said: mod size is usually a good indicator of it's performance hit. Mods of a large size are more likely to contain oversized models or textures which will lag out the game on weaker machines.

[NemesysTrans]

Thanks @Wolfi !

[bobgrey1997]

Paint jobs shouldn't be laggy any more than the vanilla trucks. A paint mod is nothing more than a texture file and some text files. Most of these are the same texture size as the vanilla or DLC paints, so they wouldn't have any more of an impact than those. That said, there are some paint mods with absolutely ridiculous texture sizes. These mods will be noticably larger in data size.
The only issue with using data size as an indicator is packs....
If yoi download a mod that has, say 5 trucks, it will be much larger than a mod with one truck, but would not cause any more lag. The truck you are actively rendering is where most of the FPS hits come from, so the other 4 trucks wouldn't have an impact. Same goes for paint packs. You might have one paint mod that has a single texture that is 16kx16k, and another with 20 textures that are all 1080x1080. The pack of smaller paints will have a larger file size, but won't cause any lag.

Really, the best way to figure out what mods are causing this lag is to test each one.
First, I would take all the large mods and remove them, then test. If the above file-size theory is correct, that alone would solve the issue. Now, add them back and remove the other, smaller mods and test. Maybe the smaller mods could also be causing it.
Once you isolate a set of mods, begin testing those mods one at a time.

Before you begin, load your laggy profile, with all of its mods, and test various situations. Does it lag while in a truck? First or third person view? What about in the forests or fields? In the city? Small towns? Day or night? In the garage? Repair/service shop?
Once you have a setting where it lags, that narrows down the mods that could be causing it. If it lags in cities during the night, it could be buildings, prefabs, or lighting. If it lags in the rural areas during the day, maybe the traffic mods (the ones that add traffic vehicles, or maybe a mod that makes traffic more dense; too many vehicles to render). If it only happens in first or third person view, it could be the truck mod you are actively using (if first person, the interior model is likely too heavy, if third person, the exterior model).
If you have multie of the same model truck, but with different paints, and it only lags when using one and not the other, then it is likely the paint mod.

Once you have a narrowed set of mods that could be causing it, this is when you look at the files themselves. Take the larger ones from the smaller ones and begin testing as explained above.

This will get very tedious, but that is the life of modding.

[NemesysTrans]

Thanks @bobgrey1997 ! Very helpful. I mostly drive in first person, I don't have any mods that change the AI traffic, so that's already that eliminated. I actually started with a brand new vanilla truck. I started adding things and testing each time. I found out so far that the Hella lights are costing between 3 to 4 fps. When your machine renders at 200+ fps, of course you won't notice, but when you're at 25, it makes a difference. I don't have any mods modifying the structures or the buildings but I found out that when it's night, the framerate drops a little, not noticeably but when the fps displayed, I can see a drop.

I will try to see if I can disable the mods. Problem is, sometimes, the game will crash if you're merely selecting a truck relying on some mods, not even driving it...

[bobgrey1997]

Yeah, when testing, you often have to use a new profile, as removing mods can cause some of the most random crashes. That only addts to the tediousness.

[NemesysTrans]

Good job by the way on the Arkansas project. That's a major undertaking @bobgrey1997 , specially on a 1-1 scale. I wish I could help but I'm not equipped at the moment to do any mapping or even less 3D creation...

[bobgrey1997]

Thanks. The project has been on a long hold for a couple years now, starting with hardware issues, leading to a lack of motivation, and now lack of time.
Mapping isn't hard to do or learn. It takes time to learn because there are so many different things to figure out. The best way to do it is to read various threads here about how to set the editor up, basic file structure of the mod, and how to package the mod to load in the next session; overall workflow. After you get it set up and establish your routine, next is to just start poking buttons and messing with assets to figure out what features the editor has and how to use them. Then, you can start a basic map; nothing serious, just something small with a few roads, buildings, and depots to form a small town to get an understanding of how maps work. This part takes the longest. You will always find something new or different that could make mapping easier than what you were doing before.