FPS drops in 0.44 compared to 0.43 related to physics

[Malak]

Hi everyone,
I just registered here due to a problem I currently have. I will probably stay on 0.43 for know because of that problem.
I tried to search a bit for similar problems here, but didn't find anything, so I hope this is not a know problem.

Anyway, after taking a break for a few months, I came back to Morrowind or openMW. I used 0.43 before the break and heavily modded it. My mod setup is more or less based on the Morrowind STEP guide, where I replaced fake bump mapped mods with normal map mods specifically made for openMW.

Important settings in openMW:
exterior cell load distance = 3

My hardware:
i-6600k @ 4.3 GHz
GTX 1060 6 GB
16 GB RAM

I noticed a massive FPS drop after upgrading to 0.44 from 0.43. In Balmora, it goes from about 30-35 to 20-25. It is most noticable in Ald-ruhn: FPS goes from 45-50 to 10-15!
In the overlay that is enabled with F3, I see high values at "physics".

With all esp and omwaddons enabled (Ald-ruhn, the spot where you are teleported with coc)
0.43: ~5
0.44: ~35

All esps deactivated (mod data and thus replacers still active; mod handling via this text file with the data folders is currently a bit too clunky for me to test it further and deactivate everything):
0.43: ~0.9
0.44 ~15

The same save was used, loaded with different esps active.
In further testing, two plugins did have the strongest effect on physics. Deactivating those two is almost identical to deactivating everything:
NX_Guards_Complete.esp (drops physics by about 5)
Starfires NPC Additions Ver-1.11.esp (drops physics by about 15)

Those two are mods that add a lot of NPCs. I already found the other thread to physics skyrocketing by NPCs collisions or something like that. Don't understand the details. I don't know if this is related to that, the thread is already closed.

I just wondered if this is well-known or if there is a problem on my end. As is stands, I will stay at 0.43 (which is not much of a problem, I found it to be pretty functional the last time I played) because the FPS is too heavy for my settings. I could reduce cell load distance, but I prefer it a 3 because there are no distance statics yet.

[akortunov]

Important settings in openMW:
exterior cell load distance = 3

Do not do it. You update physics and animation for every flying actor in the 49 exterior cells, also you update scripts for every object in this area. Use the "exterior cell load distance = 1".
There is a pull request to change this behaviour, but the game is still not designed for increased value.

It is most noticable in Ald-ruhn: FPS goes from 45-50 to 10-15!

There are mountains near Ald-Ruhn with a lot of cliffracers.

[Jemolk]

Important settings in openMW:
exterior cell load distance = 3

Do not do it. You update physics and animation for every flying actor in the 49 exterior cells, also you update scripts for every object in this area. Use the "exterior cell load distance = 1".
There is a pull request to change this behaviour, but the game is still not designed for increased value.

It is most noticable in Ald-ruhn: FPS goes from 45-50 to 10-15!

There are mountains near Ald-Ruhn with a lot of cliffracers.

Your PR was merged the very same day you posted this, I notice. Was that later in the day, so you didn't get to mention it? Either way, should be in the nightlies soon. Thanks very much sir! Didn't realize this was a thing that could be done!

[Malak]

Out of curiosity, why is the perfomance worse in 0.44 though? Did just get more physics and animation related stuff added compared to 0.43 which makes for a larger perfomance hit if more actors are loaded? The really unpexcted thing for me was that the perfomance in 0.43 was much better. I know the engine is not really supposed to use higher values of exterior cell load distance, but I got suprisingly good perfomance in the past.

[akortunov]

Out of curiosity, why is the perfomance worse in 0.44 though?

In the 0.43 we updated physics and animation only for actors in the AI processing range, so view distance did not affect physics.
But there was an another issue - actors outside processing range were frozen, but you still could hit them via ranged weapons or spells.
Especially it looked silly for flying actors since they were in the air even after death.
So Scrawl decided to update animation and physics for EVERY flying actor in the scene indifferently from distancle to player.
Since every player is supposed to use the "exterior cell load distance = 1", performance cost was considered negligable.

Now we use an another approach - actors near processing area become transparent and softly disappear, so we do not need to update physics and animations for them.