Map Performance

[Biggus]

3 hours ago, Mr_sukebe said:

Have you chaps done the usual DCS housekeeping an optimising to avoid unnecessary use of VRAM (eg disabling the Oculus home)?

If not, could I please suggest you take a scan here:

 

Not using VR.

Every one of those performance settings checked and tested multiple times in different combinations.

[Holbeach]

Here is an example of 900' ball drop, taken this morning. 70 down to 18 fps

To achieve this, I increase Unit Texture from my usual medium,, to high and usually descend from a high altitude.

 

 

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F4 falkland .trk

Edited May 17 by Holbeach

[Mr_sukebe]

8 minutes ago, Holbeach said:

Here is an example of 900' ball drop, taken this morning. 70 down to 18 fps

To achieve this, I increase Unit Texture from my usual medium,, to high and usually descend from a high altitude.

 

 

..

 

Sounds like you've identified the issue, i.e. an increase in VRAM usage at low altitudes.  As you know the cause, we also know the mitigating solution, i.e. don't use High Textures.

[Holbeach]

22 minutes ago, Mr_sukebe said:

 

Sounds like you've identified the issue, i.e. an increase in VRAM usage at low altitudes.  As you know the cause, we also know the mitigating solution, i.e. don't use High Textures.

That's exactly what I do.

Med Unit Textures gives 100% free of ball drop with no noticable difference in quality, but it shouldn't be there in the first place as it dosn't occur in any other map.

Also it dosn't always occur. It is intermittant.

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[Holbeach]

This morning I made a discovery.

If I run the track I provided, (All settings at max), it will show the 900' problem, 80fps reduced to 18 fps instantly, repeated 3 times.

If I run the same track with the Texture, (not Terrain Texture), reduced to Medium, the problem goes away and it remains at around 75 fps at low level.

This means that replays run on another machine, will be pretty much useless in this case.

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[Czar66]

23 hours ago, Mr_sukebe said:

 

Sounds like you've identified the issue, i.e. an increase in VRAM usage at low altitudes.  As you know the cause, we also know the mitigating solution, i.e. don't use High Textures.

Not a solution at all. Anything but high textures blur out the cockpits for the Huey and similar aged modules to a major degree that you can't read words on it.

• Heavier maps are fine on a 12gb VRam.
• New cards are coming with less than 12gb.
• Omitted optimization not on par with the rest of the products available.
• Needing more than 12gb of VRAM to be able to use older modules on the map in the economy today is NONSENSE. Especially if the map visuals are not the current benchmark.
• No way I'm buying a new card just for the VRAM and because a dev doesn't optimize their work.
• The issue is intermittent. It is not a RULE to saturate the VRAM just because of the map at every sortie. It is more or less a 50% chance.
• The map doesn't offer any visual quality above the rest to warrant such a bump of memory needed.

It IS a bug. Anyone can make an asset that can bring any system to a crawl intentionally. Optimization needs to be accounted or it ends up in the bug category.

12gb VRAM + 64gb RAM and I can't put the textures on high on a single map. My ass...

4 hours ago, Holbeach said:

This morning I made a discovery.

If I run the track I provided, (All settings at max), it will show the 900' problem, 80fps reduced to 18 fps instantly, repeated 3 times.

If I run the same track with the Texture, (not Terrain Texture), reduced to Medium, the problem goes away and it remains at around 75 fps at low level.

This means that replays run on another machine, will be pretty much useless in this case.

..

The "Textures" setting has been found the one to be changed. It is the setting that wrecks cockpit readability on old modules if it is not on high.

The "Terrain Texures" will blur a bit the terrain BUT still not enough to make room.....or something else is broken outside of Vram usage.

This can cause a lot of confusion. It IS the map, but changing "Terrain Textures" won't do much.

I have Iraq. It is in its own way heavy near cities and have a lot of satellite imagery, but this issue doesn't occur at all.

Edited May 18 by Czar66

[Mr_sukebe]

Sorry, don’t agree.

Also, apologies, I did mean Terrain Textures and not Textures.

Give it a try.  My guess is that at a certain altitude, we’re getting some pretty big ground textures loaded up.

[Czar66]

19 minutes ago, Mr_sukebe said:

Give it a try.  My guess is that at a certain altitude, we’re getting some pretty big ground textures loaded up.

We've already posted last year on this very thread extensive tests.

Reducing terrain textures doesn't mitigate the issue.

Thanks.

Edited May 18 by Czar66

[Raven (Elysian Angel)]

34 minutes ago, Mr_sukebe said:

Give it a try.

If it was that easy, people wouldn't have so many problems trying to reproduce it with the problem appearing one moment and then disappearing the next 
I myself for the longest time didn't have the problem, then I did, and now I can no longer reproduce it.

As with many performance issues in DCS, the cause is likely a very obscure combination of hardware, bios settings, dcs settings and perhaps even windows version and drivers...
If I were to hazard a guess, the issue is somewhere in BIOS but I could be completely wrong...

[Raven (Elysian Angel)]

Nevermind: I just had it happen again... At the end of a pretty long flight (the F-15E IA take-off mission), so I took off again after landing (I had plenty of fuel remaining) so I flew around the area dipping below and above the 900ft mark to make some screenshots. I'm not sure how useful the track is, since it only happens at the very end but I'll share it anyway:

First screenshot is while flying slightly above 900ft; 2nd one slightly below it. Behold the difference:

Malvinas 900ft performance problem 20250518.trk

[Biggus]

Seconding that it's absolutely not a VRAM limitation issue.  Was a problem for me at 8GB, has been a problem for me at 16GB.  It's been an issue reported by people with 4090s in the past. 

It's also somewhat infuriating that it isn't consistent.  With my 3070, I'd get it more often than I do with the 9070XT.  It's now on roughly 30% of the instant actions I load into, vs about 80% prior to the upgrade.  Sometimes people get lucky with masking the issue by dropping clutter, forest details and textures, but it's definitely not a normal performance issue due to limited VRAM and is absolutely a bug.  It's a pity because it's a lovely map otherwise, I just haven't been able to use the damn thing in what, two years?

[NineLine]

Thanks for all the examples and settings, I will try and see what I can see again this week.

[NineLine]

On 5/16/2025 at 6:17 AM, Biggus said:

Here's a quick demo with my current setup.  FPS limiter set to 65fps, but the effect is still the same.
Behavior is identical with all modules.  I'm using some mods in this track to change the trees from high to low and I'm also using reduced texture sizes and don't really have the patience to return to a completely stock install for this test, because the result is the same.

 

SA_frame_drop.trk 1.56 MB · 3 downloads

Edit:  My rig is a 5800X on a B450M PRO VDH Max board with 64GB at 3600, a 9070XT and DCS is installed on an M.2 drive.  The issue also existed with a 3070.  Current texture mods include resizing everything above 4096x4096 and replacing the high trees with low tree models.  These mods do not seem to mitigate it.

If I find time, or end up being sufficiently annoyed by this bug enough to make time when I can, I'll return to a standard setup and post more videos and tracks, but it feels utterly pointless because I suspect that it's something that only hits a tiny percentage of the user base.

So with your track, I was not able to reproduce, nor was I able to replicate on my own. I am still investigating but wanted to update.

On 5/15/2025 at 1:57 PM, BlowTorch005 said:

Alright, did a quick flight to check if it was still happening and the answer is yes.

Here is a track, a short 1 min flight going above and under the 750-900ft sgl where the FPS drop happens.

My PC is kinda average for DCS, so the effect may be more pronounced, but it goes from the 60fps limit down to 15.   

Can do more testing if needed, I'm eager to use this map the way it deserves.

South Atlantic low level FPS drops.trk 418.18 kB · 3 downloads

This one I also had not luck in reproducing, but I again continue to investigate.

With both of these ones, the differ in that the elevation being used was feet over ground vs feet over sea. So it wasn't 900 feet above sea level.

 

On 5/18/2025 at 9:52 AM, Raven (Elysian Angel) said:

Nevermind: I just had it happen again... At the end of a pretty long flight (the F-15E IA take-off mission), so I took off again after landing (I had plenty of fuel remaining) so I flew around the area dipping below and above the 900ft mark to make some screenshots. I'm not sure how useful the track is, since it only happens at the very end but I'll share it anyway:

First screenshot is while flying slightly above 900ft; 2nd one slightly below it. Behold the difference:

Malvinas 900ft performance problem 20250518.trk

This one reproduced as described, I was even able to take control and experience it. Its a long track, and I did try to reproduce with a different aircraft (A-10C II) and I had no luck. It is a long track, though, so I want to make sure it plays back every time. 

 

On 5/17/2025 at 8:22 AM, Holbeach said:

Here is an example of 900' ball drop, taken this morning. 70 down to 18 fps

To achieve this, I increase Unit Texture from my usual medium,, to high and usually descend from a high altitude.

 

 

..

F4 falkland .trk 1.31 MB · 2 downloads

This one was the most interesting so far. The first couple of attempts I was not able to reproduce it. After I watched the above track, and it happened in that one, I tried this one again and it then reproduced. I paused the game during the low FPS event and came back a few minutes later, and it had resolved itself, and I was no longer able to reproduce playing this track back.

But I am still investigating. Certainly something going on though.

[YoYo]

I see that a topic in which I once gathered quite a lot of sound has returned.

Here I have to defend @Raz_Specter who has made a lot of changes to the map, including optimization, during this time. For me, this map works really well now, even below 1500ft, which used to be a barrier. The map currently works no worse for me than the Kola map in terms of performance and I have good impressions of it. Gentlemen, I would like to draw your attention to another thing that appeared in DCS about 3 patches ago, DCS currently slows down and loads something after starting the game. There are quite a few posts on this topic. This applies to every map, but sometimes this symptom appears, sometimes not. So the question is whether it is not the map that is ok, and this stutter affects the entire DCS, and not just this map, which currently works well for me. Something has been changed in the CPU management and during the game there are some kind of read-ins, which results in systematic stutter for 0.01 seconds. It stops completely after 1-4 minutes. So if you are launching this map and testing, do not look at the very beginning, because that may be it. Wait at least 4 minutes and then check the performance of this map. This effect occurs 50/50. I have no diagnosis, sometimes it is there, sometimes it is not and everything is fine from the beginning. This should also be taken into account and it is best to draw conclusions after a few days of fun, not after one flight btw.

 

Edited May 21 by YoYo

[Raven (Elysian Angel)]

4 hours ago, NineLine said:

But I am still investigating. Certainly something going on though.

Yes, it’s tricky. Thanks for checking my track despite its length. This is how this issue presents itself to me these days: I used to be able to see it instantly after spawning in, but now it only happens after a long(ish) flight. I’ve had it happen again in helicopters yesterday but only after flying for 30+ minutes and then coming in to land.

1 hour ago, YoYo said:

This applies to every map

Perhaps, but it’s a different issue then. I make regular long flights and for me it only happens in the SA map. I haven’t seen it anywhere else (I world have mentioned it if I did).

[Holbeach]

Here is my track in video form.

 

Video for DCS Forum from supplied track, F4 Falklands..

This shows the sudden drop in frames when passing through 900' AGL. 

This only occurs on the Falklands map and is intermittent. I can completely eliminate it by reducing Texture to Medium, as shown.

This doesn't work for most people.

All other maps work perfectly for me at full settings.

 

 

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