[2.9.8.1214] Apache and Phantom unflyable in VR

[rubbra]

Both the F4 and Apache have become unusable for me in the most recent (Oct 2024) patch.

Point of reference - Caucasus "Takeoff" instant action for F4 gives me 2 fps. Caucasus Cold and Dark IA for Apache gives 3-5 fps, vs flying pretty much any scenario, multiplayer or single player in the FA/18 or MI-8 or MB339, where I get 72fps.

As a test, I created a new mission on Afghanistan. Placed a single UH-1 at Kandahar. 72fps. Change that unit to an Apache, 5fps.

• OpenXR, SteamVR as OXR runtime
• using PicoConnect, USB wired to a Pico 4 over USB3.
• Running at 3188x3188
• MSAA 2x
• 4070ti, Ryzen 9 3900x, 96Gb RAM

Additional/non-standard stuff - TacView and SimHaptic - but neither of those are new.

[rubbra]

Edit - this appears to only affect PicoConnect + SteamVR (as the OXR runtime).

VirtualDesktop, VDXR, Wireless - 72fps

VirtualDesktop, SteamVR, as XR runtime, Wireless - 72fps

PicoConnect, SteamVR, USB wired, 5fps

PicoConnect, SteamVR, Wireless, 5fps

In both cases, resolution is 3188x3188 or thereabouts (3200x3200 in VD's case, but what's 144 pixels between friends?)

[rubbra]

Further testing - I wondered if it was any OXR layers; I disabled everything, including quad views. No improvement.

I don't understand what is specific to the AH64 and F4 that isn't specific to the other modules. The only thing I can think of is VRAM usage; on the occasion that I can manage to manipulate a mouse cursor enough to quit the mission rather than force quit DCS, the fps recovers when back in the "debrief" screen, but only after a couple of seconds.

[5ephir0th]

AH-64 and F4 both are the most heavy modules on VRAM and SteamVR consumes VRAM too, when i had the 3080ti (with 12GB too) it was impossible to me to fly the AH-64 due to lack of VRAM using Oculus or SteamVR, i had to put ground textures to low. Using VD with VDXR takes out the SteamVR layaout from the VRAM usage so take a look at VRAM and try lowering texture detail

[rubbra]

 

26 minutes ago, 5ephir0th said:

AH-64 and F4 both are the most heavy modules on VRAM and SteamVR consumes VRAM too, when i had the 3080ti (with 12GB too) it was impossible to me to fly the AH-64 due to lack of VRAM using Oculus or SteamVR, i had to put ground textures to low. Using VD with VDXR takes out the SteamVR layaout from the VRAM usage so take a look at VRAM and try lowering texture detail

 

Yes, it's definitely VRAM - textures to medium makes it go away.

But (not a rant at you, just observations) -
a) why has that changed so much between patch versions, and why only for AH64 and F4?

b) why is it only with SteamVR with PicoConnect? I would understand it if it was still a problem with SteamVR as OXR runtime + VD, but it works just fine. VDXR vs SteamVR with VirtualDesktop is near enough identical in performance.

c) The point of using PicoConnect is because it has fewer compression artifacts/quite noticeably better image quality compared to VD

d) I know a 4070ti is *only* a 12Gb card, but it's still in the upper end of cards for VR. Do I really have to run it at low terrain and medium cockpit textures just to make it playable with a single unit? Seems crazy to me, especially after all the "optimized" vram usage items in recent patches.

[5ephir0th]

Apache and Phantom textures are huge and very detailed, way above the rest of modules, being the other one the Tomcat but not has heavy as those two.

the only “fix” i used back when i had the 3080ti is setting ground textures to low, that way i can keep the rest of textures on high, textures, resolution, antialiasing and shadows are the options that hurt most the VRAM

[AhSoul]

I dropped my textures to medium a few weeks back (as it helped with the Chinook) and honestly in my Quest 3 I can't actually tell the difference anyway.

[The_Nephilim]

well I am able to run "Textures" at Medium and "Terrain Textures" at High and no issues. if I put "Textures" on High I get over vRam usage after a while in the game.

 

So maybe a memory leak or simialr still going on in the Apache?

[jackd]

Tip: clean your shader cache files with Windows Disk Cleanup.