-30% fps when game is in focus, solved by forced DX11 but image quality is terrible - VR

[kvcsa]

Hi guys
In a given, easily reproducable situation (TF-51D cold start in krymsk instant mission, looking to the left) I have the following issues, but it happens on all the planes and maps I have tried (Caucasus, Syria, TF-51D, A-10C II, F-14A, F-14B, Supercarrier.). Changing the plane/location doesn't seem to have any effect (apart from the regular performance differences with complex modules like the F-14, supercarrier, etc.), I mean effect on the nature of the problem.
It's more apperent when 80%-ish gpu performance isn't enough for 50+ fps - above cities for example.

 

I have 40 fps and 33ms frametime when the game IS in focus.

I have 53 fps and 17ms framtetime when the game IS NOT in focus (alt+tabbed to steamVR in this case).
 

HP Reverb G1 Pro v2 (SteamVR), RX 6800 XT, Ryzen 5 5600X, 32GB 3600MHz RAM, nvme ssd.
All in Open Beta, couldn't get the cursor to work in non-beta.
Pixel density set to default 1.0 in DCS, set to 100% in SteamVR, tried with 2xMSAA just to push the GPU harder (the issue is more noticeable like that).
The issue doesn't react differently to any kind of pixel density or graphical setting, it feels like a constantant performance penalty.
GPU voltage is different in the pictures (undervolt settings didn't work then), but it doesn't affect the issue.

So the 2 problems are:
-terrible performance (both fps and frametime) when the game is in focus, compared to when the game is not in focus (can still look around like that, and there is no resolution degradation or anything like that that would justify the extra performance. With the game in focus, the gpu mostly stays around 80% usage (no cpu thread ever goes above 70-75%), even if I barely get 40 fps with 33ms frametime. With the game out of focus, gpu maintains 98%+ usage when necessary.).
-The above problem can be negated by forcing DX11 on, but it makes the image quality terrible.

The things I have tried:

-disabling fullscreen optimizations, turning off the in-game "Fullscreen" setting and turning v-sync ON as was suggested in a reddit post.
-setting the pcie slot (in which the gpu is) to gen3 (by a suggestion from somewhere), didn't help.
-a pretty stable GPU driver from march, didn't help.

-reinstalling, repairing, fxo and metashaders2 delete, tried anything that remotely looked like a possible solution.

The only thing that helped was forcing DX11 ON in Steam\steamapps\common\MixedRealityVRDriver\bin\win64\MixedRealityVRDriver.exe
EXCEPT it has introduced a terribly strong blur-like thing, like if I set pixel density to 60%, or something like that. Almost feel like a reverse-anti-aliasing. Texts clearly readable with forced dx11 OFF are mostly unreadable with forced dx11 ON. Of course this blurryness is NOT present when I alt+tab out of the game with forced dx11 off.
Like this, changing the pixel density in SteamVR definitely had its expected performance hit (setting it to 200% resulted in about 50 fps in this certain scene), but the image quality was basically the same terrible mess, didn't notice any difference, considering it's from 100% to 200% (normally I clearly see the difference between 100% and 150% for example, could test easily with gauges).
 

I have been trying to solve this unreasonable issue literally for days now (been present since I first tried the headset I bought not long ago), and I'm starting to lose faith...
And no, I don't care about "wait for vulkan" answers.

So my ultimate question is "excuse me, what the fck?" I knew VR would be a pain to optimize, but I didn't expect to see such unsolvable bugs trying to murder me behind every corner.

Thanks for the help in advance.

Edited August 29, 2021 by kvcsa
precision, fixes

[=OPS=Slider]

Well, bitter sweet that I found this thread. I'm glad that I'm not alone with very similar behaviour, but not so happy with no solution for it. In my case, DCS never exceeded 70% GPU usage. What's worse, whenever I switch between planes on a server, performance degrades immediately, from stable 45 FPS (locked on purpose) to the range of 13-20. What kind of helps, is to just alt+TAB for a moment, and when I see my FPS is back to normal, I can move focus back to DCS.

I have a Reverb G2 paired with R7 5800X, 32GB RAM and an RTX 3070 Ti. DCS is on a SATA SSD, but will be moved on an M.2 tommorow.

The annoying part is, DCS won't push my GPU any further than 70%, but it's been like that all the time as far as I can remember, no matter the hardware.

That's also the reason why I plan to switch to a 3080 Ti, because I'd rather have 70% of performance from a 3080 Ti rather than a 3070 Ti...

[kvcsa]

1 hour ago, =OPS=Slider said:

Well, bitter sweet that I found this thread. I'm glad that I'm not alone with very similar behaviour, but not so happy with no solution for it. In my case, DCS never exceeded 70% GPU usage. What's worse, whenever I switch between planes on a server, performance degrades immediately, from stable 45 FPS (locked on purpose) to the range of 13-20. What kind of helps, is to just alt+TAB for a moment, and when I see my FPS is back to normal, I can move focus back to DCS.

I have a Reverb G2 paired with R7 5800X, 32GB RAM and an RTX 3070 Ti. DCS is on a SATA SSD, but will be moved on an M.2 tommorow.

The annoying part is, DCS won't push my GPU any further than 70%, but it's been like that all the time as far as I can remember, no matter the hardware.

That's also the reason why I plan to switch to a 3080 Ti, because I'd rather have 70% of performance from a 3080 Ti rather than a 3070 Ti...

Well, I'm also "happy" knowing I'm not alone.
I'm afraid bad performance is not simply the result of the low GPU usage (like... it might not be perfectly proportional to it). So be careful about your expectations going for a 3080 ti. At least buy it at a price that allows you to resell it without a huge loss.

I'll try the forced dx11 method but also cranking MSAA to max, maybe it will help the image quality issue.

What a bummer... got the rx 6800 xt at a relatively nice price (~$1100), I could push it like crazy (xfx merc 319, basically the best air-cooler on these rx 6000 cards), but nope, the game/wmr says fck you. Just feels bad.
Some people elsewhere mentioned it might be a WMR-related issue btw. Guess I'll try completely wiping and reinstalling it.
I honestly wouldn't be surprised if a full WIndows reinstall solved the problem. Hmm...

Maybe wait with that 3080 ti purchase until Vulkan? If it really comes in Q3 this year... doubt.

[kvcsa]

On 8/31/2021 at 8:50 PM, =OPS=Slider said:

Well, bitter sweet that I found this thread. I'm glad that I'm not alone with very similar behaviour, but not so happy with no solution for it. In my case, DCS never exceeded 70% GPU usage. What's worse, whenever I switch between planes on a server, performance degrades immediately, from stable 45 FPS (locked on purpose) to the range of 13-20. What kind of helps, is to just alt+TAB for a moment, and when I see my FPS is back to normal, I can move focus back to DCS.

I have a Reverb G2 paired with R7 5800X, 32GB RAM and an RTX 3070 Ti. DCS is on a SATA SSD, but will be moved on an M.2 tommorow.

The annoying part is, DCS won't push my GPU any further than 70%, but it's been like that all the time as far as I can remember, no matter the hardware.

That's also the reason why I plan to switch to a 3080 Ti, because I'd rather have 70% of performance from a 3080 Ti rather than a 3070 Ti...

well, tried a full windows+game+wmr+steamvr reinstall, didn't solve the problem.
Maybe... maybe the blurryness of the forced dx11 is bearable with about 200% PD in steamvr... At least like this I know my GPU won't sit at 60% usage yelling "fuck you" and having 33ms frametime.
I just don't get it... it's so easy to reproduce the anomaly, so a fix (or just a "we know what causes it, we are working on it") would probably be easy. Especially because it looks like not everyone has this problem, so it seems solvable.
Losing 30% performance like this is fcking infuriating.

Edited September 4, 2021 by kvcsa