VR random Frametime spikes

[Brainfreeze]

If have recently started to experience random FPS drops in VR down to 15-20 fps for 2-3sec.

I am using the F15E /Instant action / navigation practise (ready on the ramp) mission in caucasus.  There are numerous F15s / F16s/blachawk and co planes so lots of textures / models to render.   The FPS drop happens immediately and during taxi (first 2min).

I tried to debug by removing all mods, dropping all setting, updating nvidia driver, restoring nvidia driver settings etc.  Followed @Flappie detailed list (see his post further down this page)

So far I have found just one peculiar way to prevent these spikes:   Upon starting DCS I go straight to system setting, change the visib range setting to something different... DCS restarts and my spikes are gone.  There are only gone until I restart DCS again though.

 

Logs attached. Nvidia (driver 551.23) settings are default except power management at 'prefer max perf'.  I am running out of ideas here. If someone can decipher the log and point me in a direction they would have my deepest gratitude

dcs.log DxDiag.txt

Edited February 5, 2024 by Brainfreeze

[Brainfreeze]

Done more trial on this... no amount of cleanup / repair/ removal of mods has done anything yet.
 

I have found a way to make it go away... not a nice one:

I go to settings -> change a setting that requires restart ( I pick visibility range and switch between extreme and high) ... After the restart the issue is gone... but only for this session of DCS.  

@Flappie besoin d'aide    Anything that pops given your experience?

Edited February 2, 2024 by Brainfreeze

[Flappie]

Hi. Try this: https://www.majorgeeks.com/content/page/power_settings_individual_apps.html (the path of your exe is : "C:\Program Files\Eagle Dynamics\DCS World OpenBeta\bin-mt\DCS.exe").

If that does not help, try and kill Corsair iCue before playing (a user once told me he had solved his performance issue after he uninstalled iCue).

Edited February 2, 2024 by Flappie

[Brainfreeze]

1 hour ago, Flappie said:

Hi. Try this: https://www.majorgeeks.com/content/page/power_settings_individual_apps.html (the path of your exe is : "C:\Program Files\Eagle Dynamics\DCS World OpenBeta\bin-mt\DCS.exe").

If that does not help, try and kill Corsair iCue before playing (a user once told me he had solved his performance issue after he uninstalled iCue).

 

Thks @Flappie.  Did both but no impact.  However, I can confirm that after a restart triggered by switching visibility range that issue is fixed for the session.  But only that session.  

[Flappie]

OK. I've been gathering stuff that helped people with stutters but it was a mess. I've tidied up for you:

Windows:

• Ensure your pagefile is located on a SSD.
• In Windows power management setings, select High/Max Performance.
• Turn off Windows GPU Scheduling (if it was off already, turn it on).
• Disable or uninstall RivaTuner.
• Disable or uninstall MSI Afterburner.
• Disable internal GPU if not used.
• Unplug external drives.
• Disable HPET.
• Open your antivirus settings and add and exception for "...\DCS World (OpenBeta)\".
• Disable Windows Game Bar DVR.
• Close OneDrive (especially if you backup your Saved Games and %TEMP% folders...).

DCS:

• Go to "C:\Users\username\Saved Games\DCS.openbeta", and empty both "fxo" and "metashaders2" folders.
• Ensure DCS is installed on a SSD.
• In DCS.exe properties:
  • Do NOT run DCS as Administrator.
  • Disable Fullscreen Optimization.
  • Do NOT run DCS in Windows 8 Compatibility mode.
• Go to "C:\Users\username\Saved Games\DCS.openbeta" and rename the "Scripts" folder to "Scripts.bak".
• Disable track recordings by adding this line to your autoexc.cfg: disable_write_track = true
• DCS options:
  • Disabled Hot Plug (in Controls options).
  • Lower Preload Radius value.
  • Lower Max FPS value.
  • Turn off V-Sync.
  • Turn off SSAO.

NVIDIA GPU:

• Empty "C:\ProgramData\NVIDIA Corporation\NV_Cache" folder.
• Disable NVIDIA Share.
• Undate NVIDIA driver.
• NVCP options:
  • Set Low Latency Mode to "Ultra".
  • Turn off Threaded optimization.
  • Set NVCP Power Management Mode to Maximum performance.
  • Turn off MFAA.
  • Turn off FXAA.
  • Turn off AA transparency.
  • Turn off AA gamma correction.
  • Set Negative LOD bias to "Clamp".

Intel CPU:

• BIOS:
  • Enable Hyperthreading.

AMD CPU:

• BIOS:
  • Enable Precision Boost Overdrive.
  • Disable SMT.

Edited March 3, 2024 by Flappie

[vgilsoler]

3 hours ago, Flappie said:

OK. I've been gathering stuff that helped people with stutters but it was a mess. I've tidied up for you:

Windows:

• Ensure your pagefile is located on a SSD.
• In Windows power management setings, select High/Max Performance.
• Turn off Windows GPU Scheduling (if it was off already, turn it on).
• Unplug external drives.
• Disable HPET.
• Open your antivirus settings and add and exception for "...\DCS World (OpenBeta)\".
• Disable Windows Game Bar DVR.
• Close OneDrive (especially if you backup your Saved Games and %TEMP% folders...).

DCS:

• Ensure DCS is installed on a SSD.
• In DCS.exe properties:
  • Do NOT run DCS as Administrator.
  • Disable Fullscreen Optimization.
  • Do NOT run DCS in Windows 8 Compatibility mode.
• Go to "C:\Users\username\Saved Games\DCS.openbeta", and empty both "fxo" and "metashaders2" folders.
• Disable track recordings by adding this line to your autoexc.cfg: disable_write_track = true
• DCS options:
  • Disabled Hot Plug (in Controls options).
  • Lower Preload Radius value.
  • Lower Max FPS value.
  • Turn off V-Sync.
  • Turn off SSAO.

NVIDIA GPU:

• Empty "C:\ProgramData\NVIDIA Corporation\NV_Cache" folder.
• Disable NVIDIA Share.
• Undate NVIDIA driver.
• NVCP options:
  • Set Low Latency Mode to "Ultra".
  • Turn off Threaded optimization.
  • Set NVCP Power Management Mode to Maximum performance.
  • Turn off MFAA.
  • Turn off FXAA.
  • Turn off AA transparency.
  • Turn off AA gamma correction.
  • Set Negative LOD bias to "Clamp".

AMD CPU:

• BIOS:
  • Enable Precision Boost Overdrive.
  • Disable SMT.

 

 

This can help too

Windows:

• Open your antivirus settings and add and exception for your Saved Games and %TEMP% folders and "C:\ProgramData\NVIDIA Corporation\NV_Cache" folder.

 

[Flappie]

Interesting. Have you seen a difference in doing so?

[edmuss]

Just as a sanity check, have you disabled openvr in varjo base?
There's a bug associated with varjo base and steamvr that slaughters performance for no reason, turning off openvr support seems to help

[vgilsoler]

9 hours ago, Flappie said:

Interesting. Have you seen a difference in doing so?

I saw it. I’m using a very old CPU so any load you can save, it matters.

[Flappie]

I'll give it a go, thanks.

By the way, the NVIDIA cache path has changed. It is now in "C:\Users\your-login\AppData\Local\NVIDIA".

[Brainfreeze]

could not find the NVIDIA NV_cache folder...there is a GLCache under C:\Users\****\AppData\Local\NVIDIA though.

Did absolutely everything else... Still getting these frametime spikes by default  

Not sure what happens / why it goes away if I change a setting (like visib range) that triggers a restart. Because it really solves it everytime but only until I quit that session! 

Edited February 3, 2024 by Brainfreeze

[vgilsoler]

41 minutes ago, Flappie said:

I'll give it a go, thanks.

By the way, the NVIDIA cache path has changed. It is now in "C:\Users\your-login\AppData\Local\NVIDIA".

Exclude whole %temp% from AV is a bad security practice, so I did only for %temp%\dcs and moved it to fastest drive. 

[cow_art]

Possibly related?

 

[Brainfreeze]

9 hours ago, cow_art said:

Possibly related?

 

Totally!  Exactly the same issue and same fix

[Parrotnut]

On 2/3/2024 at 9:48 AM, Flappie said:

 

By the way, the NVIDIA cache path has changed. It is now in "C:\Users\your-login\AppData\Local\NVIDIA".

I think the path has changed again?:

"C:\Users\your-login\AppData\LocalLow\NVIDIA\PerDriverVersion\DXCache"

[Flappie]

3 hours ago, Parrotnut said:

I think the path has changed again?:

"C:\Users\your-login\AppData\LocalLow\NVIDIA\PerDriverVersion\DXCache"

I don't see this on my PC (W11).

EDIT: but my NVIDIA driver is old (534.41).

Edited February 11, 2024 by Flappie
old driver

[PLUTON]

Hello everyone, for me the NVIDIA cache path does not appear there ("C:\Users\your-login\AppData\LocalLow\NVIDIA\PerDriverVersion\DXCache") there
("C:\Users\your-login\AppData\Local\NVIDIA".)
I can't find it anywhere.
HAVE A GOOD FLIGHT EVERYONE

[Parrotnut]

23 minutes ago, Flappie said:

I don't see this on my PC (W11).

Strange, W11 here also. Version 23H2. Nvidia driver 551.23

The "C:\Users\your-login\AppData\Local\NVIDIA" folder is empty for me

[Flappie]

1 hour ago, Parrotnut said:

Strange, W11 here also. Version 23H2. Nvidia driver 551.23

The "C:\Users\your-login\AppData\Local\NVIDIA" folder is empty for me

My mistake: I have an old version (534.41).

[Parrotnut]

24 minutes ago, Flappie said:

My mistake: I have an old version (534.41).

Aha, that must be it than. Thanks 

[Brainfreeze]

On 2/10/2024 at 11:12 PM, cow_art said:

Possibly related?

 

I have experimented with process lasso and found something that seems to work.  went to I/O priorities and matched DCS with low priority.  Seems to force DCS to not assign I/O E-cores. Relaunched DCS fter a reboot a couple times and I have not experienced the spikes and the log show no I/O cores assigned.   Not sure if this is affecting anything else though as I do not really know what I'm doing here    Anyway, worth a try!

[pcoud]

Hi @Flappie, currently going through your list:

• Disable track recordings by adding this line to your autoexc.cfg: disable_write_track = true

but can't find any autoexc.cfg anywhere ?

Thx

[hsth]

Filename is autoexec.cfg, you may have searched with missing "e"?

File to be found in ..\Saved Games\DCS\Config\. If it isn't there you can use the attached file that is empty.

Best edit it with tool like Notepad++. 

autoexec.cfg

[pcoud]

Many thx @hsth, there was just no such file in my DCS\Config so far

[Flappie]

Yes, this file needs to be created manually whenever you want to disable or enable certain things. In that case, the line disables DCS track recordings.