Strange FPS behaviour

[TZeer]

Noticed this on 2D mode while messing around in the mission editor. Normally I fly VR.

My specs:

AMD 5800X
32 Gb Ram
SSD Drives
AMD RX6900XT

For some reason when moving the camera around, the FPS behaves crazy.
I can have 170-200 FPS looking down at an area, turn the camera slightly, and the frames drops to 50-60 FPS.
At the same time the GPU utilisation drops from 80-100% and down 16-20%.
Turn camera again, and the frames and GPU usage comes back up again.

I have attached 2 screenshots, almost the same. 
The one with blue skies in the horizon has 75 FPS.
The one with a slightly more angled down view, has 179 FPS.

Now, you could say it's due to more "horizon" in the view of the first one. But here's the kicker. If I zoom in on the radar of the patriot site in the background. I get..... 50 FPS. Looking straight down on nothing but the radar. I would expect HIGHER FPS. As it should be easier to draw a single patriot radar, then the entire scene.

I can have the same issue inside cockpit vs external view.
Inside Apache cockpit, 150-180 FPS. Move to F2 view, 60-70 FPS. Back into the cockpit again, 170 FPS.

This is the "top down" view on the patriot radar, gives me 50-60 FPS.

I have noticed this on different maps, Nevada, Caucasus, Gulf and Syria.

Scenes where you would expect lower frames are pushing out 140-190 FPS easily. Change to a single UH-60 external view in Nevada. Tanks down to 60 FPS. Goes back to internal view in the Apace, shoots right back into 140-170...

I use Skatezillas tool to do the patching and cleaning of the DCS install everytime.

Edited July 9, 2022 by TZeer

[Flappie]

I did a simple test: make the unit disappear after some time with a fixed camera view. I get no FPS difference whether the unit is here or not (56 FPS).

Do you?

Patriot_radar_test.trk

[Karman]

I've been scouring the forum for info and it turns out that many posts from about a week ago are about fps issues. I also have an FPS problem today. I don't understand why before in 4k I had 70fps stable, and now I have drops at 45/40.. I tried everything, delete the fxo and metashaders2 folders in the saved game. Defined the grapichsconfig.lua file (in the DCS/Config root folder) with the value of 180 replaced by 300 . I still lose 20 fps when I look at an AH64.. Something that doesn't happen when any module is flying next to me.. Since 2.7, I hadn't encountered any fps problem until then; It does not mean anything. I'm looking.. ( Note: My graphics drivers are up to date, windows too etc .. )

Edited July 9, 2022 by Karman

[TZeer]

Here are some more examples.

External view in Nevada of the Apache: 58 FPS.

Cockpit view from the CPG seat with TADS running: 156 FPS

 

You can basically look at the same scenery and get completely different FPS. Based upon if you are inside the cockpit, or in F2 view.

 

Edited July 9, 2022 by TZeer

[TZeer]

This is the utilisation of my system during the screenshots.

Cockpit CPG with TADS - 156 FPS - GPU Usage: 99% ,CPU@4,3GHz

External View Apache - 56 FPS - GPU Usage: 21%, CPU@2,4GHz

[TZeer]

6 hours ago, Flappie said:

I did a simple test: make the unit disappear after some time with a fixed camera view. I get no FPS difference whether the unit is here or not (56 FPS).

Do you?

Patriot_radar_test.trk 39.94 kB · 1 download

@Flappie

Tested it. And the FPS did not change.

But I think you misunderstood me.

My point is, the FPS should have been much higher!

Something is making DCS not use all resources it has available and dumps the FPS. It's very easy to replicate. 

Please have a look at the test track. It's of the Apache in Nevada. Cockpit view from CPG, 150+ FPS. External view 60-70 FPS. Also have a look at your resource use on your computer if it behaves the same. When I go external, my CPU usage and GPU usage drops significantly!! When I move to cocpit view again, my GPU and CPU usage goes up again.

cockpit_external_test.trk

 

Edit: I just did a quick test with the Huey, F/A-18C and A-10CII. None of them are able to get above 100 FPS. The Huey was stuck at 63 FPS, A-10 around 70 FPS, and the F/A-18 was dipping around 70-90 FPS. And both my GPU and CPU was far away from their max utilisation. Something strange is going on.

Edited July 9, 2022 by TZeer

[Hiob]

Guys, it is always the same issues with high FPS. When you come close (you don’t need to hit it) to the DCS frame limit of 180 fps, it starts to act weird.

You can work around this by either increasing the GFX settings and thus lower the fps OR edit the graphics.lua in the config folder of the main game folder.

Around line 428 you change the following line „maxfps = 180“ to 300.
 

@Flappie It‘s about time that ED changes this value by default. This issue comes up regularly and can easily be reproduced.

6 hours ago, Karman said:

I've been scouring the forum for info and it turns out that many posts from about a week ago are about fps issues. I also have an FPS problem today. I don't understand why before in 4k I had 70fps stable, and now I have drops at 45/40.. I tried everything, delete the fxo and metashaders2 folders in the saved game. Defined the grapichsconfig.lua file (in the DCS/Config root folder) with the value of 180 replaced by 300 . I still lose 20 fps when I look at an AH64.. Something that doesn't happen when any module is flying next to me.. Since 2.7, I hadn't encountered any fps problem until then; It does not mean anything. I'm looking.. ( Note: My graphics drivers are up to date, windows too etc .. )

 

Your issue is of different nature. 

[TZeer]

@Hiob & @Flappie

That worked!! Thanks Hiob.

External FPS in Nevada went to over 300 FPS!

FPS inside Huey, A-10CII and F/A-18C went skyhigh!

And @Flappie, the testtrack with the Patriot radar went to around 320 FPS or something!!
 

[Flappie]

Thanks gents.

@Hiob I wasnt aware of this issue. I cannot reproduce it. This is what I did:

• Set graphics global option to Low
• Set resolution to minimum (1024x768)
• Loaded my very simple mission
• Zoomed on the only unit

My FPS are constant: 180, whether I zoom in or out. I have a 1080Ti.

What I am missing?

Edited July 9, 2022 by Flappie

[Hiob]

10 minutes ago, Flappie said:

Thanks gents.

@Hiob I wasnt aware of this issue. I cannot reproduce it. This is what I did:

• Set graphics global option to Low
• Set resolution to minimum (1024x768)
• Loaded my very simple mission
• Zoomed on the only unit

My FPS are constant: 180, whether I zoom in or out. I have a 1080Ti.

What I am missing?

 

Hmm, that I can‘t tell.

Usually this issue happens to people with high-end GPUs (3080, 3090, 6900 and so on), that for whatever reason play on a small resolution or low details.

I can personally reproduce it reliable with my 3080 and helped at least three people with this work around. You can see my post history for the according threads.

Maybe (just wildly guessing here) the software implementation of a fps cap in DCS can’t keep up with the raw muscle power of latest highend gpus?

EDIT

I mean the cure is simple enough. There is really no harm in upping the fps limit. It‘s just annoying that it is overwritten by every update.

(I think you can add this modification to an autoexec in the savegames folder, but I don’t know how to do that exactly, and haven’t looked into it yet)

Edited July 9, 2022 by Hiob

[Flappie]

Just now, Hiob said:

I can personally reproduce it reliable with my 3080 and helped at least three people with this work around. You can see my post history for the according threads.

Yep, I saw that. And I can see your solution works for them.  But I need to reproduce the issue myself to report. Otherwise, I won't be able to test any fix.

1 minute ago, Hiob said:

Usually this issue happens to people with high-end GPUs (3080, 3090, 6900 and so on), that for whatever reason play on a small resolution or low details.

That's what  I did. I know my 1080 Ti is not the youngest highend GPU around anymore, but still I can reach a steady 180 FPS without the bug triggering.

Can you please attach screenshots of your NVIDIA 3D options?

[Hiob]

10 minutes ago, Flappie said:

Yep, I saw that. And I can see your solution works for them.  But I need to reproduce the issue myself to report. Otherwise, I won't be able to test any fix.

That's what  I did. I know my 1080 Ti is not the youngest highend GPU around anymore, but still I can reach a steady 180 FPS without the bug triggering.

Can you please attach screenshots of your NVIDIA 3D options?

Yeah, but your GPU is two generations old. Different architecture perhaps? (No disrespect - the 1080ti is one of the best GPUs ever. I still own one and would never give it away!)

Sorry, I‘m not sitting at my rig. My NvidiaCP is all default, except for g-sync is enabled and v-sync forced off.

But I can tell you already, that all this stuff doesn‘t make a difference. I did tons of testing with it.*
(Well, though it's true, that I did a LOT of testing with settings, it wasn't specifically in regards to this issue. So that claim was a little to bold.)

Perhaps you can ask a fellow beta tester with a beefier GPU to try to reproduce?

Edited July 9, 2022 by Hiob

[TZeer]

@Flappie

You could try put a single unit into a very very deserted area of Caucasus or Nevada. Any map that is a  low resource hog. Also on a part of the map that is not used yet. No buildings, no trees etc. You should then be able to get the most out of the card. 

My guess is that you need to have quite a bit of extra "horsepower" left for this to trigger. 

Only the map, I would get 64 FPS. With the Huey cockpit roughly the same. A-10CII moved it up to about 70 FPS, and F/A-18C gave me about 90 FPS. The more intensive the cockpit/scene was to render. The higher the FPS went. Thats why I got such an extreme difference on the apache cockpit and external view. I was not able to reach or go past the limit of 180 FPS with the apache cockpit.

You need to see how much GPU usage you get from your 1080Ti when running 180 FPS.

[Flappie]

7 hours ago, TZeer said:

@Flappie

You could try put a single unit into a very very deserted area of Caucasus or Nevada. Any map that is a  low resource hog. Also on a part of the map that is not used yet. No buildings, no trees etc. You should then be able to get the most out of the card.

See my track. That's exactly what I did. I got 180 FPS as expected, but it stayed that way.

I'll ask other testers to do the same test.

[TZeer]

8 minutes ago, Flappie said:

See my track. That's exactly what I did. I got 180 FPS as expected, but it stayed that way.

I'll ask other testers to do the same test.

Ok, but what was the utilisation of your GPU. Is it at 40% or 90%?

And are you refeering to your first track posted in response to me? I guess 56FPS was with your normal settings then, and 180 was with reduced settings?

And do you have any max framerate active on driver levels?

I had Nvidia before, and I know there is a setting somewhere for maximum FPS.

Edited July 10, 2022 by TZeer

[Flappie]

3 minutes ago, TZeer said:

And are you refeering to your first track posted in response to me? I guess 56FPS was with your normal settings then, and 180 was with reduced settings?

Yep.

3 minutes ago, TZeer said:

And do you have any max framerate active on driver levels?

I had Nvidia before, and I know there is a setting somewhere for maximum FPS.

I checked yesterday to be sure:

[TZeer]

@Flappie

But what is your GPU usage?

I went from 63 fps and up to 320 fps without changing any settings.

[Hiob]

When the fps are limited (either due to a maxfps setting or a bug) the gpu usage should be low(er). 

The Scenery doesn’t really matter for this issue to happen. It’s just easier in outside shots to hit high framerates. 

@Flappie Do you have an intel or amd cpu? Perhaps the different behavior isn’t gpu related in the first place. I‘m not 100% sure, but the guys that had this problem, all had a amd iirc.

Edited July 10, 2022 by Hiob

[Flappie]

My rig: Ryzen 5 2700X - 1080 Ti -32 GB RAM

@TZeer No idea about my GPU usage during the test.

[Hiob]

Then I‘am out of ideas for now. It may very well be a matter of hardware.

I could test on a 4790K + 1080ti, but I would have to install DCS first.

[TZeer]

@Flappie

Ok. Was just curious. Cause if you where close to max gpu usage @ 180fps. You will not see this behaviour. If you have MSI afterburner installed, you can use it to log your GPU usage in the background.

One last thing you could check. You don't have a startup file overriding your graphics.lua settings?

If you have stable 180 fps, without maxing you GPU and CPU, and max fps in graphics.lua set at 300. You have some other issue holding you back.

 

@Hiob I found one of the topics where you assisted another guy with the same issue. 4k resolution, max 50 FPS etc. He was using a 3080Ti, so it's not just AMD but all GPU's of higher performance level.

 

This should really be fixed by ED in an update. Imagine how many people out there are running 3070, 3080, RX6800 or better GPU's and getting performance way below what their systems are capable of. It's a quick and easy fix.

Edited July 10, 2022 by TZeer

[Hiob]

42 minutes ago, TZeer said:

 

 

@Hiob I found one of the topics where you assisted another guy with the same issue. 4k resolution, max 50 FPS etc. He was using a 3080Ti, so it's not just AMD but all GPU's of higher performance level.

 

I was referring to the used CPU, not GPU.

Due to the unusual boost-behavior of AMD-CPUs it may be that the algorithm used by DCS is over correcting when throttling the fps output. But that is wild guessing. I have no clue how DCS tries to manage this.  

[Flappie]

10 hours ago, Hiob said:

Then I‘am out of ideas for now. It may very well be a matter of hardware.

I could test on a 4790K + 1080ti, but I would have to install DCS first.

I think so. That is why I'll ask other testers to give it a go.

[Karman]

I confirm the last update killed the fps..   Concretely since the release of the AH64, there is something broken in terms of fps.