investigating The longer I fly Apache, the greater the drop in fps.

[Miro]

After takeoff 45 minutes a stable 60 fps constantly flying over las vegas, and suddenly the drop to 43 fps, GPU and CPU reaches 100%, in this mission there is nothing but free flight, there is nothing to drain resources there. I can't upload track because of size.

dcs.log DxDiag.txt

Edited March 25, 2022 by Miro

[Miro]

https://drive.google.com/file/d/18EhKUB0P0x2mjtzEFjo9PfPsZ6JmzJVd/view?usp=sharing This is the track file, this can be useful. Between 42-47 min from takeoff FPS goes down.

 

[XPACT]

Unlike GPU where we want full utilization when CPU starts hitting 100% a lot of weird things start to happen (random FPS drops, audio cutting out/popping, slow loading of assets etc) and even tho GPU is reporting 100% utilization it may very well be bottlenecked by CPU.

Judging by the picture of task manager, your video memory is maxed out which caused GPU to also rely on shared memory (your system memory aka RAM). Because of that both CPU and GPU now have to wait much longer for necessary information and that causes significant FPS hit.

If you are keeping ground textures on high I would suggest that you turn them down to low and check how its working now, there is of course visual difference between high and low but it will save considerable amount of video memory and I personally think it is worth it.

8GB GPUs are really starting to hit the limit when it comes to DCS and maximum textures.

[Miro]

16 minutes ago, XPACT said:

Unlike GPU where we want full utilization when CPU starts hitting 100% a lot of weird things start to happen (random FPS drops, audio cutting out/popping, slow loading of assets etc) and even tho GPU is reporting 100% utilization it may very well be bottlenecked by CPU.

Judging by the picture of task manager, your video memory is maxed out which caused GPU to also rely on shared memory (your system memory aka RAM). Because of that both CPU and GPU now have to wait much longer for necessary information and that causes significant FPS hit.

If you are keeping ground textures on high I would suggest that you turn them down to low and check how its working now, there is of course visual difference between high and low but it will save considerable amount of video memory and I personally think it is worth it.

8GB GPUs are really starting to hit the limit when it comes to DCS and maximum textures.

Agree but first 45 min of flight is absolutely good, constant stable 60 fps, low over the city, and only Apache related. Sure, i can lower visibility range from extreeme to high, textures to low but why? Sim works good, but bug appears and i report it.

[NineLine]

Yeah I think its a matter of just running our of VRAM over long play. I think dialing in your settings would be the best approach. 1080 should be good, but not great, DCS is hungry for VRAM. I wouldnt be surprised to see some optimizing of the module as we go along as well, but for now, try dialing in your settings, view range, etc. 

As well, you dxdiag file isnt complete so I cant see anything beyond your GPU currently.

[The_Nephilim]

11 hours ago, Miro said:

Agree but first 45 min of flight is absolutely good, constant stable 60 fps, low over the city, and only Apache related. Sure, i can lower visibility range from extreeme to high, textures to low but why? Sim works good, but bug appears and i report it.

 

[Miro]

@NineLine Yes, it can be Vram related, maybye any leak? Because in other airframes problem don't exist (even f-16 with TGP ON keeps stable 60 fps over Las vegas). Today problem occurs when i enabling Digital NVG on IHADS after 40 mins or more in air, FPS don't back to normal after i turn it back off, they raised but don't reach initial fps. You cannot reproduce because got better machines than mine   But many people have. Full DxDiag attached.

DxDiag.txt

Edited March 26, 2022 by Miro

[KoN]

DCS is an old engine . And Needs a overhaul .

VR is struggling .

The more Modules we get  the worst i think it will become With better cockpit graphics and Damage modeling things will start to down grade performance wise .

DCS needs a game change . And the spotting needs a BIG fix .

Edited March 26, 2022 by KoN

[River]

this

[Miro]

UPDATE: When i don't use Digital Picture on IHADSS (in my case NVG) i can fly whole 1.7h long flight over Las Vegas without FPS drops. Standard NVG works good, MFCD > VID > Video causing big drops, but after disabling Video transmit FPS go back to normal. Only Digital image on IHADSS causing drop which still present after completly disabling it.

Edited March 26, 2022 by Miro

[NineLine]

Hey Miro, thanks for the update, can you give me a short track, show exactly the sequence where you get the drop, would be good for diagnosing. Thanks!

[KoN]

2 hours ago, Miro said:

UPDATE: When i don't use Digital Picture on IHADSS (in my case NVG) i can fly whole 1.7h long flight over Las Vegas without FPS drops. Standard NVG works good, MFCD > VID > Video causing big drops, but after disabling Video transmit FPS go back to normal. Only Digital image on IHADSS causing drop which still present after completly disabling it.

 

Fps drops in MFD TADS . When turned off fps go back to normal  .

I'm locked at 40fps . 

[Miro]

8 hours ago, NineLine said:

Hey Miro, thanks for the update, can you give me a short track, show exactly the sequence where you get the drop, would be good for diagnosing. Thanks!

I'll try but it's not that simple, at first 40 mins of flight FPS seems back to normal, after that time everything go messy, so problem looks more complex. If You can run track sent by me in first post, he is pretty showing whole situation. But, if You can't run that long track i'll try reproduce it earlier, but i don't know can I fit in these magical 40 minutes.

Sequence when problem occurs: Cold Start, and after 45 mins of flight, turn on Digital NVG on IHADSS, fly a little, turn off IHADSS (leaving Digital NVG on), fly a little, turn off Digital NVG switch to off.

Edited March 27, 2022 by Miro

[Miro]

7 hours ago, KoN said:

Fps drops in MFD TADS . When turned off fps go back to normal  .

I'm locked at 40fps . 

With my rig, I am doomed to be a pilot, every image from external cameras like FLIR, etc. causing FPS drop to 40. But I'm happy to be a pilot so no problem with that.

[Senchay]

Hello.

Im enjoying the Apache a lot! What an amzing beast.

Sadly i run into some problems with the performance. Im not sure if its some certain missions or degradation over time, but after a while the flight goes down to 5 fps (not exaggerated) and just becomes unflyable.

Overall the performance seems a hefty difference to lets say the F18. I dont have th worst PC plus im someone who takes a lot of care what he does with his pc. Its all up to date, DCS installed not even a week, no mods or anyting. Only the F14, F18 and the Apache, plus some maps.

The last time it happened was in a mission that comes with the addon, COIN in the mountains or something in English. Persian gulf. After nearing the destination the fps went down to 5, taking the whole pc with down with it. 

In the F18 i get steady 60 fps in most scenarios, in the Apache often only 20. 

My system is
Intel 9900k (no oc)
RTX 2080 (no oc)
32GB Ram 3200
WQHD resolution

Win 10 22H2

Am i alone with this?

[Miro]

Got same problem, even created a topic, but devs cannot reproduce. Looks like Video memory leak. When i start misssion, i got stable 60 FPS, the longer i fly the less FPS i have and this is bad, considering it's an empty mission with no other vehicles.

[BIGNEWY]

posts merged 

We are looking for this issue when we have our longer sessions, but I have not reproduced so far. 

[Mad_Shell]

7 minutes ago, BIGNEWY said:

posts merged 

We are looking for this issue when we have our longer sessions, but I have not reproduced so far. 

I suspect that if it's a VRAM leak problem, that may cause problems for cards with 6 or 8 GB of VRAM, but not for your 3090. Would not surprise me if it was the reason you can't reproduce it.

Edited March 31, 2022 by Mad_Shell

[BIGNEWY]

I have a beast of a machine, the team have lower end machines also so if there is an issue they will find it. 

Note that Syria terrain has some memory tweaks to come in the future also. 

[Miro]

1 minute ago, BIGNEWY said:

I have a beast of a machine, the team have lower end machines also so if there is an issue they will find it. 

Note that Syria terrain has some memory tweaks to come in the future also. 

I fly over Nevada, it's not map problem, it's module related. Besides, I came to the conclusion that it is not only the fault of the additional images being turned on on the MFD and IHADSS, because sometimes, but not always with longer flights, the frames drop regardless of this. There is also one other thing, often after turning additional images on and off, the frames come back, not to the original level, but come back. But it takes them a long time, even up to several minutes. All mission conditions, weather and time, always the same.

[5ephir0th]

1 hour ago, Mad_Shell said:

I suspect that if it's a VRAM leak problem, that may cause problems for cards with 6 or 8 GB of VRAM, but not for your 3090. Would not surprise me if it was the reason you can't reproduce it.

 

Not only on 6/8gb cards, 12gb cards too.

Definitely a VRAM leak or a poor optimized textures, not only on Apache but in general

[Lurker]

Just as an aside remark. Running out of memory should not be happening in any app, if the app works with the minimum of listed memory, then if it is indeed running out of memory that for all and effects and purposes means that you are dealing with a memory leak. In programming terms that is called a bug. In most cases this results in crashes. 

Edited March 31, 2022 by Lurker

[Rapierarch]

On 3/26/2022 at 6:04 AM, NineLine said:

Yeah I think its a matter of just running our of VRAM over long play. I think dialing in your settings would be the best approach. 1080 should be good, but not great, DCS is hungry for VRAM. I wouldnt be surprised to see some optimizing of the module as we go along as well, but for now, try dialing in your settings, view range, etc. 

As well, you dxdiag file isnt complete so I cant see anything beyond your GPU currently.

Hi, I have tried it with everything set to low and it still exceeds 8GB vram after 20-30minutes. Same problem I had too with Hind and I did not buy it. 

If I use medium textures so that I can read at least the cockpit labels it immediately starts asking for 12GB VRAM in very short time. It even starts above 8GB after spawn. 

F-16 has similar problem too but you can easily play an hour before VRAM finishes. 

[Miro]

From today's flight, CPU and GPU not maxed out, but FPS goes down, GPU Vram i got maxed everytime, in other modules too, but other modules runs in stable 60. With TracIR everything below 60 makes Military Sim Unplayable for me by by jerking, jumping of Headtracking (i bet every TrackIR user knows that pain)

[Migo]

I also thought of a memory leak with apache module. The more often I restart a mission the less fps I get, and this continues even in the menu after quitting the mission. Running a 3080 with 12gb.