SteamVR - DCS Waiting

[Matis]

Hello, 

 

so i have spent my whole weekend trying to figure out how to best set up my DCS for VR, unfortunately i am becoming to be desperate.
I recently was fortunate enough to upgrade to RTX 3080 Ti and also to HP Reverb G2, but i am struggling to get playable performance even with such card in the sim.
My other specs:
32GB RAM
I7-8700K
SSD

 

After starting any mission (multiplayer) i get on ground about 8 to 20 fps (tested on Marianas, Channel map with warbirds).
Sometimes i have between 20 to 30 fps but after about few minutes or seconds it drops to about 11-8 fps. What i see in my headset is DCS freezing / stuttering with SteamVR loading window.

In singleplayer it is better with about 25 to 35 fps (depends on the mission) but the sudden drops are still there.

What is worse is that SteamVR loading window appears extremely often that is just unplayable - happens with both multi and singleplayer - i tested this with Normandy / P-51 Charnwood campaign and Spitfire campaign.

It seems that SteamVR is disconnecting with DCS - on ground, at flight .... everywhere. 

 

I am only playing DCS in VR, previously with GTX 1080 (non-Ti) and Rift S i was not experiencing as much stuttering and i NEVER had SteamVR loading window appeared.

 

I was trying to get reasonable performance by changing settings in DCS, NVIDIA, WMR, SteamVR but even putting VR resolution to 50 percent in SteamVR and later in DCS to 0.5 did not helped at all.

 

In the screenshots are my final settings.

In DCS setting MSAA was turned off, Anisotropic filtering was set to 2x, terrain textures were set to low - none of that seems to influence the stuttering / SteamVR loading.
I only managed to get slightly better performance with terrain detail set to 0.2 - but still as i have mentioned i have 8 to 20 fps on the ground and 30 to 45fps in the air.

 

Unfortunately it does not end there, even in flight where i have 30 to 45 fps i experience sudden drops from about 40 fps to 17 fps for a second, then to 35fps, to 22fps to 37fps ... and so on.

It stutters so much that i just have no choice just to quit the mission. 

 

Restarting DCS DOES NOT HELP.

 

Also other thing i noticed is that with WMR and SteamVR after starting mission in DCS and with mentioned 20 to 30 fps on ground after few minutes it drops to 11fps - when i checked Task Manager, i have noticed that suddenly SteamVR has 6 or so new proccesses.
I also tried to end these proccess, but after few moments there are another sudden fps drops either way.

 

It looks like WMR and SteamVR are not 100 percent compatible with one another. Please let there be a way to just play DCS with WMR software only.

 

If anyone knows of some possible solution i could try please let me know i will be very thankful.

I am now starting to think that the problem is not in setting the graphics but maybe in my RAM, since it struggles mostly where there are a bit more populated maps / or in multiplayer, but 32GB should be enough at least in singleplayer or not?
 

[FoxTwo]

In my experience, any disk IO operations will completely destroy frame rates. DCS being a single threaded game will stop or interrupt draw calls frequently enough during loading that steamvr gets really, really upset with it when this happens. Try increasing preload radius to around 75000 and see if that makes any difference. I cannot say that it will but it's possible.

 

I would also not run higher than MSAA 2x at that resolution. You can also try setting the render target at 80% in steamVR.

 

Alternately, look into the FSR modified DLL for openvr, which does work with DCS (https://github.com/fholger/openvr_fsr).  If you do that you'll want to set your render target back to 100% but adjust the cfg file to render at ultra quality (.77). This will render the game at 2433x2377 and upscale the image (with contrast adaptive sharpening) to your target resolution. It's not QUITE as good as native 100% but it's very close and the performance gains are significant. It can add some shimmering so if you do use FSR, you can try 4x MSAA again and see if that helps.

 

One last thing; close any background apps using your GPU. Discord, game launchers, web browsers, etc. Close everything except what you need to run DCS.

Edited September 26, 2021 by FoxTwo

[Matis]

Previously i had preload radius to a higher values close to max, i think by increasing it would only eat more RAM. I found also suggestions online to keep preload radius between 45000 - 50000 unless spare ram is available. But it seems that on fps it should not have much impact.

 

I tried several times before combination with MSAA and Anisotropic filtering, thought i cannot see much of a difference. But i will try as you suggest 2x MSAA with 80% in steamVR.

Although i tried before lowering rendering in steamVR to 50% but strangely no difference in DCS. 

 

FSR modified DLL for openvr i do not what it is but i will check it out thanks 

(idealy i would rather not be using any other 3rd party software for that matter)

 

Regarding background apps, besides DCS all i have running is WMR, SteamVR and OpenHardwareMonitor.