Low FPS with Low GPU usage DCS 2.8

[MavOne96]

Hello fellows,

As it was the case with previous verisons this bug still persists in 2.8 for me.

I can't get DCS to use my GPU at its maximum potential. GPU usage is all over the place bouncing up to 70-80% with low FPS around 60-70 varying up to 80-90 at higher altitudes. I have attached various photos with my settings and with the actual performance taken both in multiplayer and is singleplayer.

Here are my specs:

Processor    AMD Ryzen 7 5800X 8-Core Processor 3.80 GHz
Installed RAM    32.0 GB
System type 64-bit operating system, x64-based processor
Edition    Windows 11 Pro
Version    22H2    Installed on    ‎29/‎10/‎2022
OS build    22621.819
GPU    Nvidia 3080Ti
Nvidia Driver    526.86    Release Date    11/10/2022
OS and DCS storage    Samsung SSD 980 Pro 1TB

I don't see any bottlenecks nor limits in my system and I have already tried multiple settings and solutions found on other threads (vsync on-off/fast in game settings and Nvidia Control Pannel, setting fps limits to 144 etc.) but nothing worked.

Do you get the same issues or have other solutions that I should try?

Thanks.

(GPU usage in multiplayer) 

(GPU usage in singleplayer)

(DCS Settings and Nvidia Control Panel)

Edited November 11, 2022 by MavOne96

[Flappie]

Do you have an autoexec.cfg file in your "Saved Games/DCS.../Config/" folder? If so, please attach it here.

[MavOne96]

5 hours ago, Flappie said:

Do you have an autoexec.cfg file in your "Saved Games/DCS.../Config/" folder? If so, please attach it here.

Hello Flappie. Thank you for your reply. Unfortunately I can't find the file you are asking for neither in Saved Games Folder nor in the DCS Folder. Is there any other file I could provide you with?

 

Edited November 12, 2022 by MavOne96

[Flappie]

It's OK: this file does not exist by default. It is sometimes used to set the FPS limit ingame, which is why I asked about it.

Please ensure your Windows power plan is set to the maximum.

[MavOne96]

21 minutes ago, Flappie said:

Please ensure your Windows power plan is set to the maximum.

Setting Windows power plan to best performance pushed up GPU usage by about 10% but it still jumps around 70-80% max never above 90%. In Nvidia Control Panel Power Management is set to Prefer Maximum Performance.

Edited November 12, 2022 by MavOne96

[Flappie]

Good.

Are you using a third -party software to boost FPS? I'm talking about the usual MSI Afterburner, Aorus Graphics Engine, Asus GPU Tweak...

I'm asking because DCS badly reacts to them sometimes.

Oh, I forgot: if you have a "Saved Games/DCS.../Scripts/Export.lua" file, please attach it here.

[MavOne96]

7 minutes ago, Flappie said:

Are you using a third -party software to boost FPS?

No I don't use any third party software to boost performance.

Export.lua

[Flappie]

Thank you. The first two lines are repeated. I'm not sure this is causing your issue, but you should remove them anyway.

For now, simply rename your "Export.lua" file to "Export.lua.back", so DCS cannot find it. Then restart DCS and see it changes anything.

[SkateZilla]

The DCS:Blackshark profile in nVidia's Drivers is setup for BS DX9c, DCS World Runs DX11 now, dunno if nVidia maintains that profile or not.

Secondly, there is no Hardware bottleneck in your rig, the behavior you are seeing is the software bottlenecks of the core and the DX11 API.


Visibility Range, Civilian Traffic, Shadows and Clouds have a big impact on render driver overhead of DX11, try reducing those settings first.

MSAA Also is a FPS Killer in Deferred Shading engines (like DCS), you may get better results turning on MSAA and using SS1.5/2.0x

[MavOne96]

SOMEHOW IT WORKED! 98% GPU usage. Should I do something about Export.lua now?

5 minutes ago, SkateZilla said:

dunno if nVidia maintains that profile or not.

I tired limiting the FPS to 144 and it worked so I think it saves the profile.

Edited November 12, 2022 by MavOne96

[Flappie]

25 minutes ago, MavOne96 said:

SOMEHOW IT WORKED! 98% GPU usage. Should I do something about Export.lua now?

Awesome!

Then I'm pretty sure it's caused by the call to a WinWing script in your export.lua:

local wwtlfs=require('lfs')
dofile(wwtlfs.writedir()..'Scripts/wwt/wwtExport.lua')
local wwtlfs=require('lfs')
dofile(wwtlfs.writedir()..'Scripts/wwt/wwtExport.lua')
pcall(function() local dcsSr=require('lfs');dofile(dcsSr.writedir()..[[Mods\Services\DCS-SRS\Scripts\DCS-SimpleRadioStandalone.lua]]); end,nil);
local TheWayLfs=require('lfs'); dofile(TheWayLfs.writedir()..'Scripts/TheWay.lua')

As you can see, lines 1 and 2 are repeated.

1. What you can try first is rename your "Export.lua.back" to its proper name, "Export.lua". Remove lines 1 and 2, then run DCS.
2. If the issue is back, then remove the remaining WinWing lines (the ones with "wwtlfs" in it).

Edited November 12, 2022 by Flappie

[MavOne96]

So, I tried to isolate the issue to the Export file and while the export file is not recognised by DCS I restore to default all the settings in Nvidia control panel (unlocking the fps and setting the vsync to use the 3D application setting) and the issue is back: usage is all over the place averaging around 60-70%.

Then I reapplied all the previous settings and the issue persists usage around 70%. 

I can't put a finger on the issue as the usage remains low despite letting the export file unrecognised.

Though the issue dissapeared after changing the name of the export file and with NVCP setting applied (maximum FPS to 144 and vsync to fast). 

I believe the problem is somewhere between vsync, fps limits and maybe this export file. In the past on older versions before 2.8 I had the same issue but I solved it by limiting the fps in NVCP and disabeling vsync but with 2.8 GPU low usage came back and persists despite reapplying the same settings.

Edited November 13, 2022 by MavOne96

[HeavyGun1450]

I dont think it has nothing to do with his system. Since DC's game engine runs on such a old, outdated core engine, from my understanding the game basically uses a single thread for everything except audio. However, due to the way Windows distributes threads across multiple cores, it's now technically using multi-cores, but without any of the benefits, as it's only single threaded. Basically whats happening is you have such a powerful GPU, but the CPU cannot pump enough information to the GPU not because of the CPU's speed, but because of the software limtations of DC's core engine, which causes GPU utilizations lower then 100%. This issue becomes more prevalent on faster gpus, lets say you have a really powerful CPU like a 5800x in OP's case, if it were paired with say a much slower gpu such as a GTX 1070, even with DC's core engine limitations, you would see 100% gpu usage on a GTX 1070. But say you go to a 3080ti which is a much faster GPU, even though the CPU is still plenty fast enough to supply the gpu with frames in a optimized game, in DC's case the CPU cannot feed the GPU with enough frames due to the core engine poorly utilizing the cpu. 

 

[MavOne96]

7 minutes ago, HeavyGun1450 said:

in DC's case the CPU cannot feed the GPU with enough frames due to the core engine poorly utilizing the cpu. 

I don't believe this is the issue as prevously I had instances where GPU usage was constant over 95% and fps around 120 even on ground/carrier.  

[Flappie]

I've just noticed I had not aksed fro your dcs.log yet. Can you please attach it along with your dxdiag log?

[MavOne96]

5 hours ago, Flappie said:

your dcs.log yet. Can you please attach it along with your dxdiag log

Here are the files you requested.

DxDiag.txt dcs.log

[Flappie]

Thank you. I haven't found anything funny, except maybe this mod, that I don't know about:

2022-11-13 15:14:11.668 ERROR   VFS (Main): VFS_open_write: CreateFile(C:\Users\vladc\Saved Games\DCS.openbeta\/Scripts/Hooks/lottafGameGUI.lua): The process cannot access the file because it is being used by another process.

Maybe you've installed it recently because it was absent from your Export.lua file. You can try and disable it to see if it has any influence on DCS performance. If not, I'm short of new ideas at this point.

[TZeer]

He could try and change his max_fps setting in the config.lua file, then turn off the max FPS in Nvidia.

I had issue with my RX6900 XT being underutilized, and very low FPS combined with low GPU usage. Changing the max_fps in the config.lua to 300 or so, boosted my FPS from 50-60 to well above 200 inside certain cockpits and outside view. For some reason the default max_fps in DCS messes with the FPS output from high end GPU's.

What I found out, the more overhead the GPU had, the more it held back the FPS. Huey gave me the worst frames, while the Apache gave me the best. Until I did F2 view, then the FPS dipped the same way it did on the Huey.