solved random VR frametime spikes

[noxyd]

Hi folks, 

I feel like I've read every topic, tried every potential fix, followed every VR guide for DCS.
I still have random frametime spikes that makes the game almost unplayable from time to time. 

My hardware/settings : 

- CPU : 12600K @4.9Ghz all cores
- RAM : 32Gb Gskill DDR4 3600mhz C15-20-20-39 Gear 1
- GPU : EVGA 3080 Ti FTW3 Ultra, 1935 mhz@875mv
- SSD : WD SN850 1Tb
- VR : Reverb G2 (with v2 cable)
- Virpil WarBRD base + Warthog stick + Warthog Throttle
- Fresh win11 installation
- SteamVR beta + WMR for SteamVR beta
- DCS OpenBeta
- Latest nvidia drivers
- Mothing smoothing forced 
- SS 100%, PD 1.0
- I play only MP

 

My problem : 
- When I spawn, frametime is excellent, everything is fine and in the green. After a few minutes (2-10), I have sudden frametime spikes while flying (could be yellow, red or pink, or all of them). It’s not just a matter of time because it doesn’t happen if say i stay on the ground and don’t do anything.

- I can usually make spikes disappear by clicking on the steamVR window a couple of times (or Alt+Tab, or going to the task manager), but after a few occurence, there's nothing more I can do and it's not playable anymore. 

- I'm not able to identify what trigger this. Haven't found any specific thing. 
 

What I did : 

- Followed speed-of-heat tutorial (thank you) 
- tried putting everything back to stock (no OC)
- disabled fullscreen optimization for DCS
- no weird export file
- cleared metashaders
- no RGB or monitoring software running

Any help would be greatly appreciated

Edited March 9, 2022 by noxyd

[speed-of-heat]

A couple of things to check:

-gpu and cpu temp, though if everything is at stock, that's not likely

- what code is running in task manager ordered by cpu usage when it hits...

My guess is something environmental is eating your CPU. @Flappietends to be much better at diagnosing strange perf issues than me

[noxyd]

Thanks for this quick reply.

- CPU and GPU temp are both below 60 (GPU is watercooled) 

- I will take a screenshot of task manager and report 

 

[Flappie]

Salut noxyd,

Please try these one by one:

1. If you have a "Saved Games/DCS.../Scripts/Export.lua" file, rename it so the game cannot find it (e.g. "Export.lua.bak"). Some external scripts (WinWing, DCS-BIOS...) can cause stutters or low FPS when they are conflicting with each other.
2. Go to Windows Power settings panel and ensure it's set on "High Performance".
3. Ensure your pagefile is not stored on a slow drive, such as an HDD. To do this, run this command in a 'cmd' window: wmic pagefile list /format:list
4. Check your RAM health using the Windows Memodry Diagnostic tool, or MemTest.
5. Activate the NVIDIA control panel Debug mode:"Help" > "Debug Mode".
6. EDIT: Another idea, disable your internal graphcis card (either in BIOS or in Windows device manager).

Still got FPS drops?  Run Windows Resource Manager, maximize it, go to Disk tab, ensure the disk timings are displayed. Run DCS, select DCS.exe in the Resource Manager process list, then go back to DCS. Wait for the FPS drops, then go back to the Resource Manager to take take screenshots of the disk timings, and attach them here.

 

Oh, and please send me your dxdiag.log (howto).

And your dcs.log file ("Saved Games/DCS.../Logs/dcs.log" - may appear as just "dcs").

Edited March 9, 2022 by Flappie

[noxyd]

I’ll do my homework and will report back as soon as I can !

I really appreciate the support, thanks!

[Pocket Kings]

Is that an NVMe or SATA SSD you have?

Also, you didn't specifically say whether the FPS drops disappear on their own after X amount of minutes or if the system stays stuttery.

What is your preload number? Standard 100,000?

Edited March 9, 2022 by Pocket Kings

[noxyd]

The WD SN850 is a pcie 4.0 nvme drive (that’s the only one in my system, no hdd).

I do not believe the fps drops go away if I don’t do anything (Alt+tab or other). 

preload is at max

Didn’t have time to test Flappies suggestions yet but I will as soon as I can. 

thanks all!

Edited March 10, 2022 by noxyd

[noxyd]

@Flappie Find attached dcs log file as well as DxDiag. Many thanks in advance for your help.

Didn't have the chance to play since my initial post, but I will as soon as I can. 

dcs.log

DxDiag2.txt

Edited March 13, 2022 by noxyd

[Flappie]

I see several errors in your dcs.log file and one in your dxdiag log:

dcs.log

2022-03-09 03:33:42.619 ERROR   EDCORE: Failed to load C:/Program Files/Eagle Dynamics/DCS World OpenBeta/CoreMods/services/LeapMotion/bin/edLeapMotion.dll: (126) Le module spécifié est introuvable.
...
2022-03-09 03:34:02.073 WARNING DX11BACKEND: alive vertex buffers: 1
2022-03-09 03:34:02.073 ERROR   DX11BACKEND: Failed assert `DX11VertexBuffer::buffersCount() == 0` at Projects\render\dx11backend_win8\Source\DX11Renderer.cpp:122
2022-03-09 03:34:02.073 WARNING DX11BACKEND: alive index buffers: 1
2022-03-09 03:34:02.073 ERROR   DX11BACKEND: Failed assert `DX11IndexBuffer::buffersCount() == 0` at Projects\render\dx11backend_win8\Source\DX11Renderer.cpp:123

The game is unable to load the Leap Motion dll. Although this shouldn't bother you if you don't use such device, it's not good to see the game complaining about a missing DLL... You should run a DCS repair.

I have no idea why the game complains about "DXINdexBuffer:bufferCount" when the game is about to close, but I've seen this before. Users with this symptom told me their game would never close on its own. Are you having this issue?

 

dxdiag log

Quote

      Display Tab 3: There is a problem with Intel(R) UHD Graphics 770 device. For more information, search for 'graphics device driver error code 22'

I'm thinking maybe your FPS issue is caused by your Intel internal GPU interfering with your NVIDIA GPU. If you're not using it all, I suggest you to disable it in the BIOS.

Your BIOS manual is here: https://download.gigabyte.com/FileList/Manual/mb_manual_600series-bios_e.pdf

Go to Advanced Mode (F2) > Settings > IO Ports > Internal Graphics > Disabled.

 

Edited March 13, 2022 by Flappie

[noxyd]

So I disabled my iGPU in BIOS and did a DCS repair (long).

i check disk timings and saw nothing specials

no change

will provide new DXdiag and DCS log tonight, as well as disk timing screenshot.
 

A few things I thought of :

- I did a full fresh DCS install last week (because before that I copied DCS folder from an old disk instead). But I kept the saved games folder. No change. Should I try another one but with deleting the saved games folder prior ?

- I notice that if I disable motion smoothing in SteamVR I don’t get those spikes. Can it be a Motion Smoothing problem then ? 
When everything goes well the forced-MS experience is better (for instance when I look on the sides flying low at tree level it’s smoother). But when the spikes kick in it’s terrible.

- I find interesting that with forced MS, the graph is green, but disabling MS it becomes orange (with a similar frame time) is this normal ?  

- should I try non beta versions of SteamVR and WMR for SteamVR ?

- forgot to mentioned that I’m not using any mods.

- I tried another MP server yesterday and got the same issue. 
 

I will disable MS for now. 
Any other idea ?

many thanks again 

[Flappie]

51 minutes ago, noxyd said:

 I did a full fresh DCS install last week (because before that I copied DCS folder from an old disk instead). But I kept the saved games folder. No change. Should I try another one but with deleting the saved games folder prior ?

Simpler: just rename your "Saved Games/DCS..." so the game cannot find it. It will create a brand new one. You'll have to enter your login and password and then you'll see if the issue persists.

53 minutes ago, noxyd said:

 I notice that if I disable motion smoothing in SteamVR I don’t get those spikes. Can it be a Motion Smoothing problem then ?

I'm not a VR user, so I don't know much. How is your VR gear connected? Is it through a USB hub? If so, try to plug it directly on the computer with Smoothing enabled, and see it if that changes anything.

55 minutes ago, noxyd said:

 should I try non beta versions of SteamVR and WMR for SteamVR ?

If the previous actions don't prevent the spikes, yes, you should give it a try.

[Quip]

Check here.

Imho, the frame times is a symptom, not the cause. This is deeply worrying

[noxyd]

Quick update :

It turns out that my motherboard was recalled (Aorus z690i DDR4) because of a hardware issue creating thousands of WHEA errors.

Upon receiving the new one (Aorus Z690i Ultra Plus….), I switched to OpenXR instead of SteamVR and the spikes are gone. 

Not sure if only one or both things above fixed my issue though!

Thanks to those who helped, much appreciated. 
 

[Flappie]

Many thanks for your feedback. Enjoy the game without the spikes!