WMR devs identify performance bottleneck between SteamVR and WMR (copy from Reddit)

[SYN_Luftwaffles]

I found this little gem while perusing the Reverb G2 sub this morning. It's above my head, so I thought I would share it with you guys and maybe you can make heads or tails of it. I also have a question: can you bypass SteamVR by using only the IL2 launcher? 

 

"Yesterday in r/WindowsMR a WMR developer said that the only current way that the WMR for SteamVR plugin and SteamVR's OpenVR API can interface is through copying the screen buffer.

This can consume large amounts of memory because of the G2 100% size (2160*146%) , especially when supersampling.

They have found a possible solution with sharing a screenbuffer both parties are working on.

This is a shortcoming of SteamVR's OpenVR API, which despite its name is pretty much bound to Valve hardware and implementation, with support for other HMDs bolted on by plugins.

The only structural way to prevent problems like this is OpenXR, which all VR manufacturers including Valve are pushing.

Each manufacturer there has complete control over their implementation of the API. No more fitting square pegs through round holes.

The difference in performance can already be seen when comparing games like MSFS and Revive with SteamVR vs OpenXR WMR native support. People having stutters when going through SteamVR -> WMR for SteamVR run butters tooth under OpenXR alone.

For now we need to wait for the fix, and the only things we can do to minimize impact of this problem is lower the amount of screen buffer copies on the GPU, and keep those buffers small by reducing superfluous supersampling (RR auto).

• Clean install Nvidia 461.40 driver

• Disable WMR 4 virtual desktop default in Registry

• Start WMR

• Set desktop res to 1080p 60 Hz when WMR is on

• Move your steamvr.vrsettings file from the Steam program dir (only needed once) to a backup directory. This resets SteamVR settings to default, including hidden GPU profiling info. This is never cleared any other way, like reinstalling SteamVR. Also resets custom bindings, but if you can edit JSON you can merge app specific settings back into the new file which is created at start

• Start SteamVR

• Set Rendering Resolution to Custom:100% instead of Auto to disable dynamic supersampling.

• Always leave OpenXR implementation on WMR, never set it to Steam's implementation.

• Restart SteamVR

• Tweak per game settings from there

Render Resolution: Auto hits 30x0 cards harder because the architecture is seen as twice as powerful, so supersamples far higher. It doesn't take into account its memory size and bandwidth stay roughly the same, so the screen buffer copy problems are more pronounced."

[dburne]

I use Open XR for WMR for MSFS 2020 and it does good.

Sounds like Open XR for Steam VR may not be so much. I have never tried it.

But I am getting good performance in Steam VR , at least not seeing the stuttering some do.

I did disable the extra virtual desktops some time ago.

I run my G2 at 100% resolution for IL-2 and forced motion smoothing at 45 fps.

 

 

Edited February 20, 2021 by dburne

[kissTheSky]

Encouraging news if true. I’m still waiting for my G2 to ship, and am under no illusions I’ll be able to run IL-2 comfortably on my system, but perhaps might be able to run it if there’s a more streamlined implementation in the near future. 

[Dijital_Majik]

This is good news, any potential performance gain, no matter how big or small, is welcome.  The WMR team have really been putting out some cracking updates these past few months, and have identified and fixed quite a few issues.
 

1 hour ago, SYN_Luftwaffles said:

I also have a question: can you bypass SteamVR by using only the IL2 launcher? 

 

 

Only those on Oculus AFAIK, using Open Composite.  It did make quite a difference when I used to use it, but now on WMR.

[SYN_Luftwaffles]

What is your system? I shopped locally at a small store (Gigaparts) and scored not only a G2, but also an RTX 3070 on the same day. 

I went from my Odyssey+ and a 2070 Super getting anywhere from 40-60 fps on high settings to the G2 with the 3070 to 50-70 at the same settings (albeit a TON clearer - can't stress that enough) on a system with 16gb of RAM and an 8700k. That is in multiplayer, btw. Test flying in QM I get a stable 90 fps at the same settings. 

I come from a 1080p 60hz monitor, so the 60 fps doesn't bother me. 

5 hours ago, kissTheSky said:

Encouraging news if true. I’m still waiting for my G2 to ship, and am under no illusions I’ll be able to run IL-2 comfortably on my system, but perhaps might be able to run it if there’s a more streamlined implementation in the near future. 

 

[kissTheSky]

1 hour ago, SYN_Luftwaffles said:

What is your system? I shopped locally at a small store (Gigaparts) and scored not only a G2, but also an RTX 3070 on the same day. 

I went from my Odyssey+ and a 2070 Super getting anywhere from 40-60 fps on high settings to the G2 with the 3070 to 50-70 at the same settings (albeit a TON clearer - can't stress that enough) on a system with 16gb of RAM and an 8700k. That is in multiplayer, btw. Test flying in QM I get a stable 90 fps at the same settings. 

I come from a 1080p 60hz monitor, so the 60 fps doesn't bother me. 

 

I have a 2080 super.   I guess I won’t be getting anywhere quick with the GPU. I’m going to have to wait for an RTX 30xx to become available in stock, I guess. 

[Drum]

The G2's res is so good I run my settings at low with all the setting boxes ticked with only clouds turned down one notch, and I'm getting 90fps steady low over Stalingrad city with 16 (8vs8) planes in quick missions.  If I drop to street level the buildings are crisp looking with zero flickering or blur and might see the fps drop into the 80s sporadically.  Even at this setting I hardly notice a drop in the graphics, in fact I can see further without zoom and don't feel the need to use it much.

 

I'm perplexed about that as well, because why would the medium to long view become so clear at range with lower settings?  I can run with reprojection locked at 45 fps with high settings and that too is smooth as silk, only negative I experience with reprojection on is it feels like I'm traveling slower; smooth but I lose that cense of the buildings zipping by at 500kph like I get with the reprojection turned off...

 

Still playing with settings, but for those wondering if they can run a G2 with a 20xx card and still get crisp looking graphics, heck yes, the res is so so good even on low settings.

 

Edited February 21, 2021 by Drum
can't spell

[peregrine7]

20 hours ago, Drum said:

The G2's res is so good I run my settings at low with all the setting boxes ticked with only clouds turned down one notch, and I'm getting 90fps steady low over Stalingrad city with 16 (8vs8) planes in quick missions.  If I drop to street level the buildings are crisp looking with zero flickering or blur and might see the fps drop into the 80s sporadically.  Even at this setting I hardly notice a drop in the graphics, in fact I can see further without zoom and don't feel the need to use it much.

 

I'm perplexed about that as well, because why would the medium to long view become so clear at range with lower settings?  I can run with reprojection locked at 45 fps with high settings and that too is smooth as silk, only negative I experience with reprojection on is it feels like I'm traveling slower; smooth but I lose that cense of the buildings zipping by at 500kph like I get with the reprojection turned off...

 

Still playing with settings, but for those wondering if they can run a G2 with a 20xx card and still get crisp looking graphics, heck yes, the res is so so good even on low settings.

 

 

The HDR implementation (and lighting/haze in general) is fundamentally different between "LOW" and "Balanced" presets - regardless of what you clicked for all the other settings. Spotting can be a lot better on the Low preset, but in some conditions it is far worse (planes blending in to forests etc).

[Drum]

Like an idiot, I failed to read everything and never undated my HMD device with the 'HololensSensors.inf' driver specifically used for the G2.  With that properly installed now, the image looks much better with less blur on the outer edges, plus other things such as bright flickering when loading into the game, etc.

 

My experience with the G2 now is much more impressive to say the least!  Please disregard everything I said in the last post as things are now working properly...

[unlikely_spider]

31 minutes ago, Drum said:

Like an idiot, I failed to read everything and never undated my HMD device with the 'HololensSensors.inf' driver specifically used for the G2.  With that properly installed now, the image looks much better with less blur on the outer edges, plus other things such as bright flickering when loading into the game, etc.

 

My experience with the G2 now is much more impressive to say the least!  Please disregard everything I said in the last post as things are now working properly...

What is that driver? Can you elaborate?

[Drum]

dburne posted this, read his first suggestion for extra reading, it explains how to update your driver.  It auto downloads when you first plug your G2 in it claims, but there was an issue with mine I guess because after reinstalling it the headset's noticeably better.

 

Edited February 22, 2021 by Drum

[firdimigdi]

On 2/20/2021 at 6:21 PM, SYN_Luftwaffles said:

also have a question: can you bypass SteamVR by using only the IL2 launcher? 

 

Not for WMR headsets - you need SteamVR since IL2 is an OpenVR-using title (easy way to tell: openvr_api.dll is present in the bin\game folder) - if it was converted to use OpenXR then you could play right away (as is the case with MSFS) without needing SteamVR to act as intermediary.

Edited February 22, 2021 by 335th_GRFirdimigdi

[II./JG77_Manu*]

Many thanks for letting us know @SYN_Luftwaffles. Please post here as soon as this is sorted by the WMR team, I'd like to revisit IL2 and see if I can finally run it properly then. 

[SYN_Luftwaffles]

https://www.roadtovr.com/steamvr-update-brings-full-support-openxr-1-0/amp/

[dburne]

2 hours ago, SYN_Luftwaffles said:

https://www.roadtovr.com/steamvr-update-brings-full-support-openxr-1-0/amp/

 

Excellent news.

Open XR does a really good job with MSFS 2020.

[kissTheSky]

So I’m not clear if this requires input/revisions by the developers, or if this takes cares of the implementation on its own automatically. I’m guessing it’s the second, but wanted to make sure. 
 

I’m quite sure that I’ll be needing all the assistance with a 2080 super. 

[II./JG77_Manu*]

12 hours ago, SYN_Luftwaffles said:

https://www.roadtovr.com/steamvr-update-brings-full-support-openxr-1-0/amp/

 

So is there anything the consumer has to do now in order to get better performance in titles like IL2?

[SvAF/F16_Goblin]

IL-2 don't support Open XR as far as I know. It's up to the devs to implement that.