Microsoft Mixed Reality using OpenVR performance questions

[Duderei]

Happy New Year,
i have been going through multiple VR guides and settings the last couple of days and had some great racing experiences. However I am still not satisfied with the FPS drop I experience.

I have things set up that I can run at 90 FPS with my Lenovo Explorer VR Headset in practice mode/ benchmarks. I am also running a test server on a different machine and when I connect to that I still have ~90 FPS. When I switch to a different online server with the same track and NO other drivers being connected my frames drop to about ~45 FPS.

Is that an issue with net code or because latency of ~120 to 150 ms?

If net code/ connection latency is causing this, so be it, but I don't want to miss something because 90 FPS "feels" a lot better than 45.

I realize I am not running the latest machine with a I7 3770K @ 4.4 GHZ with a GTX 1060 - 6GB but what is throwing me off is the vast difference between connecting to my LAN server vs. any WAN Servers.

Anybody with the same experience or some ideas how to improve FPS with the online servers?

 

[RasmusP]

Indeed strange as you already tested some things.
2 things that hit the performance, hidden, on the CPU (ac isn't very well multithreading so it can't utilise the whole CPU):
- apps! Move your cursor to the very right and click on the top symbol to disable all apps. Fast and an easy check for CPU performance.

- max server slots! If you take a track with a lot of slots and you enable them all, your fps will go down. This is independent of the actual player numbers!
Load up something like pacific Coast with about 100 slots on your own server. My I7 2600k @4.4GHz will go down to 40 fps when I'm alone on the server.
Lower the available slots to 10 and I'll get 150+ fps!

I hope this helps. Report back when you texted these 2 things

 

[Duderei]

...i tested as you suggested and I can confirm that
a) apps take a few FPS for me - between all of and the few it want it is less than 5 FPS
b) The number of slots makes a difference as you suggested even without any cars being connected.

I tested Pacific Coast with 2 slots and had ~90 fps in the parking lot and when I started to drive down the road.
The exact same with 110 slots and I start at ~45 FPS in the parking lot

Looks like that is as good as it gets for now...

 

[RasmusP]

...i tested as you suggested and I can confirm that
a) apps take a few FPS for me - between all of and the few it want it is less than 5 FPS
b) The number of slots makes a difference as you suggested even without any cars being connected.

I tested Pacific Coast with 2 slots and had ~90 fps in the parking lot and when I started to drive down the road.
The exact same with 110 slots and I start at ~45 FPS in the parking lot

Looks like that is as good as it gets for now...

Hm, kind of "happy that I was right" but of course it's sad that you can't get to stable 90 fps with your i7!

btw: When I host races I really like to keep an eye on my drivers and substanding is the only app that gives me that. But it kills so many fps at Racestart, that I sometimes struggle to keep my v-sync 60 fps.. I feel you man..

It's so frustrating that your CPU only gets utilized to around 40% and then it is limited by the single thread performance...

Anyway what you can do/try:
Overclock your CPU higher. Up to 75°C are no problem for our CPUs. The numbers floating around are often messed up due to the difference between the measured core temp and the critical temp in a different place of the CPU.
Just keep the core voltage lower than 1.30V and you shouldn't endanger your CPU!
(Of course I can't guarantee that but I overclocked all my friends CPUs when they asked me and I read about 1000 pages all over the internet)

Don't deactivate HyperThreading or cores for a higher CPU clock though. Tried 3 cores at 4.9 GHz and got less fps than 4.4 GHz and HT + all cores!

What you can try regarding the ingame settings:
- Anisotropic Filtering to 8x (strangely AF hits the performance a lot in AC)
- World detail: less detailed track -> fewer draw calls for the CPU
- lower shadows one step. Not sure if it makes a difference..

All shimmering or reflecting things hit the CPU a little bit.
- lower glare one step
- deactivate heat shimmering
- lower reflection resolution one step
- lower the rendering frequency
- if you use content manager: lower the rendering distance a bit

That's all I know about it and what would I try.

That said: Try the AF and reflection frequency first!

Good luck

 

[Flibbberflops]

Just to clarify... I don't think you have got a massive drop in frame rate, you have just got the VR reprojection kicking in.

On all VR systems there is a clever system which keeps the 90 FPS constant for VR by doubling the frame rate. When the system detects you can't keep up the 90FPS, it cuts it to 45 FPS and then does something far less GPU intensive to effectively guess every 2nd frame. Therefore the game is renedering at 45FPS but the headset gets 90FPS.

If you want to get a huge increase in FPS, use the Shadow disable patch to completely remove shadows. This has a huge effect and may get you back to the raw 90 FPS (however, I must say the difference between raw 90 FPS and reprojection FPS isn't that different).

 

[Duderei]

...another day of testing has provided me with some insights, also thanks your comment Flibbber in regard to the reprojection. You assumption is correct. I didn't realize the option was turned on in Steam VR but the system realizing that it cannot hit 90 fps switched it over to 45 FPS.

Since I have fixed that I have tested settings to come as close as possible to 90 FPS if not hitting them. As suggested multiple times in countless threads, APPS are "costing" a noticeable amount of frames. Unfortunately Sidekick is one of the major culprits and had to go. I am now down to pretty much Helicorsa only and Crew Chief for Car spotting warnings.

I also noticed that Steam VR Frame timing tool is great in identifying the bottleneck as it shows if your CPU or your GPU is "late" - at least that is what I can make out of it. That showing that CPU is my issue and also helped me to sort out the APPS slowing me down.

 

[pitman]

Very interesting topic.
Thanks Dude.

I drive with the Lenovo explorer and experience the same problem. I am able to drive with 90 fps in offline races, but online it drops to 45 fps.
(i5 4690k, GTX970)

After reading your answers, I have some more questions:

- Is there a noticeable difference between racing with 90 or 45 fps (with VR)?
Does it feel smoother, or not?

- Why is there a connection between more slots > lower frames? Why does the server switch automatically?

-Is it even possible to reach 90 frames on a server with 22 slots.

 

[bigbawmcgraw]

You might want to reduce your ingame settings.
I have a i7 7700 and GTX1080SC and run AC at very low gfx settings and get 90fps even with a full grid online. It might sound like it will look terrible but really it looks great, especially as I never drop below 90fps.
I also use the shadow disable patch.
You might also want to completely uninstall nVidia drivers using guru3d DDU before installing the latest driver... http://www.guru3d.com/files-details/display-driver-uninstaller-download.html
This made a noticable difference too.

Here are my settings....

 

[bigbawmcgraw]

After reading your answers, I have some more questions:

- Is there a noticeable difference between racing with 90 or 45 fps (with VR)?
Does it feel smoother, or not?

- Why is there a connection between more slots > lower frames? Why does the server switch automatically?

-Is it even possible to reach 90 frames on a server with 22 slots.

1. 90fps is less blurry when you move your head, but even at 45fps it's still smooth.

2. More slots = more CPU usage (car physics calculations)

3. Yes, depending on your hardware and if you reduce graphics settings in game.

 

[RasmusP]

2. More slots = more CPU usage (car physics calculations).

This doesn't make sense for me. I know that this happens but why do invisible, not used cars get some calculations?
Some memory usage I would understand of course. But using so much CPU? For what?
You connect to a server with 60 slots and you are completely alone. What does the CPU calculate with the other cars?
Not really questioning towards you, but I'd be really interested...

 

[Neilski]

why do invisible, not used cars get some calculations?

I've wondered the very same thing! Feels a bit bananas, especially given the lack of threads to share the work.
I guess they need the calculations cos they sit there in pit row making burbling noises as the engines tick over

 

[bigbawmcgraw]

This doesn't make sense for me. I know that this happens but why do invisible, not used cars get some calculations?
Some memory usage I would understand of course. But using so much CPU? For what?
You connect to a server with 60 slots and you are completely alone. What does the CPU calculate with the other cars?
Not really questioning towards you, but I'd be really interested...

I'm sorry, I thought you meant more slots = more cars on track. Yes it only calculates cars that are on track, not empty slots.

 

[Neilski]

I'm sorry, I thought you meant more slots = more cars on track. Yes it only calculates cars that are on track, not empty slots.

Hmm, no I think I've seen people state categorically that they see a performance drop even with no other drivers on track - just more slots in server.
[EDIT: yes, in this very thread in fact! LOL, I'm clearly replying to too many threads on too many website and losing the plot...]

 

[bigbawmcgraw]

Hmm, no I think I've seen people state categorically that they see a performance drop even with no other drivers on track - just more slots in server.
[EDIT: yes, in this very thread in fact! LOL, I'm clearly replying to too many threads on too many website and losing the plot...]

Can't say I've ever noticed that tbh. You will notice a drop in frame rates at the beginning of a race if there is a full grid and lots of crashes but dropping the gfx settings does help a lot and imo doesn't look any uglier in VR.
Here is a video I made today, with I think around 20 players. My ingame settings are the same as above (saturation is now 100%).
Note the top left is the frame counter and it doesn't drop below 90fps even with the usual T1 carnage. Granted most of the crashes were behind me and not visible but the calculations are still made on your CPU.

 

[magzire]

You might want to reduce your ingame settings.
I have a i7 7700 and GTX1080SC and run AC at very low gfx settings and get 90fps even with a full grid online. It might sound like it will look terrible but really it looks great, especially as I never drop below 90fps.
I also use the shadow disable patch.
You might also want to completely uninstall nVidia drivers using guru3d DDU before installing the latest driver... http://www.guru3d.com/files-details/display-driver-uninstaller-download.html
This made a noticable difference too.

Here are my settings....

What SS are you using? That's pretty low settings, I have everything on max with PP/shadows off and reflection low. I only have a 10603gb and it never dips below 90.

 

[bigbawmcgraw]

What SS are you using? That's pretty low settings, I have everything on max with PP/shadows off and reflection low. I only have a 10603gb and it never dips below 90.

I have it running at 1.7 but haven't tried increasing it since lowering the gfx settings. I could probably increase it a little without loss of frames. That'll be for tomorrow.

 

[Duderei]

I am still trying to balance SS vs. better in game setting, AA and AF.
Do you mind to share, because I haven't found the best settings yet for my I7 3770K with a GTX 1060 6 GB.

 

[bigbawmcgraw]

What SS are you using?

I just tried SS at 2.0 and it never dipped below 90fps with a full grid. I was 16th place and there were crashes in front of me and behind me in T1 (I miraculously never got hit).
And it does look noticably better too, if only slightly.