Good FPS, but stil lag and choppines

[Gunfreak]

In a busy mission I have 45-75fps but there this constant choppines. It feels like I have low fps, even tho fps counter doesn't agree. I have between 3 and 8ms cpu and 8-16ms in GPU.

[jurajs84]

Hi, same problem. My fps is good enough (min. 38 Black Shark III free flight), but it feels like 15 FPS. 

[Flextremes]

Guys: you really need to report more detailed information. Like what hardware are you using and how are you running VR? 

[festr]

close all programs in the background - like everything and retest 

[Temetre]

So I feel like that too, and im curious if its the same for you: Is the game actually lagging, or is it the head movement?

For me, I found that when I keep my head straight and dont move, and then make the aircraft pitch and turn, everything is smooth. But when I turn my head, or move it sideways, its extremely stuttery. Almost like theres some kind of "overshooting" back and forth ghosting. So the plane and world around is fine, its actually the head movement that stutters.

If had no better way to put it, it kinda feels like theres some kind of smoothing forced, that works for the planes movement (motion vectors?) but completely screws up my head movement. That is despite having SteamVR smoothing and ASW disabled.

 

This issue is only in MT for me (which forces OpenXR), while ST+OpenVR is fine.

---------------------

That is using Pico4 + SteamVR for both OpenVR/OpenXR.

Edited March 12, 2023 by Temetre

[Bearskin]

1. DCS exe started through VD

1a. DCS exe started through launch game with the VD streamer

2.DCS exe shortcut with the force vr open xr line started through VD

2a DCS exe shortcut with the force vr open xr line started through launch game with the VD streamer

3.MTDCS exe started through VD or the launch game with the VD streamer

4. MT DCS exe shortcut with the force vr open xr line started through VD or the launch game with the VD streamer.

I have the same problem with the stuttering, with options 3 and 4 only, but for the first time since I swapped out the Rift for the Pico I can get 90 FPS external view looking up at the plane from underneath, so the MT patch is working, free flight in the HOG I have gained 15 to 20 percent.

So for example, sat on the runway it is good, but like Temetre says as soon as I move my head, it is like it is running at 10 FPS, with everything stuttering and bouncing, even though I am getting 60 to 70 FPS. When I chose a quick mission with options 3 and 4, the MT ones, like I have read on other pages, the plane and scenery take about 30 seconds to load, starts off with the sea, then renders bits of plane and scenery a bit at a time, the few posts I have read where this and the stuttering is happening only seems to be with Pico 4 users (correct me if I am wrong) 

Starting with option 1 opens Steam VR, option 1a doesn't start Steam VR, options 2,2a,3 and 4 all start Steam VR even though option 3. launch game with the VD streamer should work the same as 1a unless open xr has been coded into MT like it was when openxr was first available for DCS, before it was taken out and the shortcut method was introduced. 

I haven't tried opencomposite yet as the MT patch was making me feel sick for the first time, in VR.

I am really looking forward to the next few patches where hopefully the stuttering a few of us are experiencing could be solved.

Edited March 12, 2023 by Bearskin

[Skuva]

Stuttering and movement lag with head translations are commonly consequences of high latency.

I noticed with VD, after some update (not sure which, cause I didn't use it for months) my latency went from 40ms to 80ms, for no aparent reason. Even tho fps is good, gpu and cpu usage with plenty of headroom, tested with various bitrates. VD's overlay says the latency is coming from the "game" and not from "decode" or "network", so i'm sure it's not my router.

It might be something wrong with VD, it might be something wrong with DCS changes on vr api. It might be both. For now I'm using airlink, it still has its problem, but at least I don't feel like throwing up.

[Temetre]

Im using the Pico 4 streaming assistant, both in wired and wireless mode. Then SteamVR for with OpenVR/XR. Only MT+OpenXR has the problem.

Its hard to tell if the head movement issue is more common with lower framerates ("low" being 60-70), high CPU/GPU usage or high latency, since those things coincide often. But Ive not noticed issues at this scale in other games (MSFS 2020) or in DCS ST (which also has low FPS+latency). Then again, most other games dont put this much load on my 6+6 CPU cores, and I dont think I got other OpenXR games to test.

For me, the latency, which can be 50-70 in those situations, usually comes from game+encode, according to Pico 4 Streaming Assistant App overlay. The latency alone usually doesnt cause head tracking stutter in OpenVR applicatoins, however.

 

It is really difficult to tell whats going on. Im not envious of ED having to figure out whats going on, lt alone answering if this issue is even directly caused by DCS.

vor 2 Stunden schrieb Skuva:

It might be something wrong with VD, it might be something wrong with DCS changes on vr api. It might be both. For now I'm using airlink, it still has its problem, but at least I don't feel like throwing up.

Probably worth mentioning you use a Quest 2 btw, someone speculated the issue might be limited to Pico 4. 

Edited March 13, 2023 by Temetre

[Bearskin]

So I tried opencomposite and DCS world crashed, so that is out, next I started DCS without FPSVR and it is stutter free, still in the game I started FPSVR and it was stutter city again, closed FPSVR and stutter free. So for me turning of FPSVR fixed it. 

 

 

[ignition22]

I found that fixing the framerate to a maximum, in my case to 45fps finally got rid of the micro stutter of the ground passing below and most of the in cockpit stutter. I have an AMD card so set it in the AMD software but there is probably an equivalent in Nvidia and I think there may be a DCS config file that can be used to set it as well. Note that it made the game menus a bit rough but the game itself much smoother. My theory is that headsets and/or VR software have difficulty with a constantly changing framerate and making it consistent smooths things out. Worth a try.

[Temetre]

Hm, I just noticed something peculiar, maybe connected. For some reason, my first CPU core is always at 100% after starting DCS in MT+VR. Even in the main menu with fps caped to 40. Even in flight with FPS capped to 20 (70fps uncapped). No matter what I cap the FPS to, im always 2-3 fps below that. And the FPS drops more when I move my head, like its dropping frames.

When I play MT non-VR DCS, I get 160fps and no CPU core is fully maxed.

vor 4 Stunden schrieb ignition22:

I found that fixing the framerate to a maximum, in my case to 45fps finally got rid of the micro stutter of the ground passing below and most of the in cockpit stutter. I have an AMD card so set it in the AMD software but there is probably an equivalent in Nvidia and I think there may be a DCS config file that can be used to set it as well. Note that it made the game menus a bit rough but the game itself much smoother. My theory is that headsets and/or VR software have difficulty with a constantly changing framerate and making it consistent smooths things out. Worth a try.

I dont think AMD got an FPS limiter in their settings; at least not without forcing Vsync, which id recommend against. You can use OpenXR toolkit to limit frames. Wasnt overly succesfull to me.

Edited March 13, 2023 by Temetre

[flucifer]

15 hours ago, Bearskin said:

So I tried opencomposite and DCS world crashed, so that is out, next I started DCS without FPSVR and it is stutter free, still in the game I started FPSVR and it was stutter city again, closed FPSVR and stutter free. So for me turning of FPSVR fixed it. 

 

 

I tried without FPSVR and it made no difference. Very smooth choppines...

[gwizdek]

10 hours ago, Temetre said:

I dont think AMD got an FPS limiter in their settings; at least not without forcing Vsync, which id recommend against. You can use OpenXR toolkit to limit frames. Wasnt overly succesfull to me.

In my experience it's better to use RTSS Rivatuner Statistics Server to limit FPS than the one from OpenXR Toolkit which doesn't work that well.

Edited March 14, 2023 by gwizdek

[ignition22]

12 hours ago, gwizdek said:

In my experience it's better to use RTSS Rivatuner Statistics Server to limit FPS than the one from OpenXR Toolkit which doesn't work that well.

 

I set it using amd radeon chill settings but yeah some FPS limit settings may be more successful than others

[average_pilot]

For me it's like if the frames were not coming at a steady pace. The best way to notice it it's getting used to the MT version and then go back to ST. The smoothness gets you almost by surprise. I'm not using reprojection in either case since I grew quite tired of the artifacts. I'm using a Reverb G2 at 60Hz.

The higher headtracking latency mentioned earlier makes sense. I don't know where to look for that statistic myself though.

Edit: The OpenXR Toolkit "Turbo mode" is coming to my mind. I may try again disabling it.

Edit2: It was already disabled...

Edited March 15, 2023 by average_pilot

[Temetre]

Am 15.3.2023 um 09:56 schrieb average_pilot:

For me it's like if the frames were not coming at a steady pace. The best way to notice it it's getting used to the MT version and then go back to ST. The smoothness gets you almost by surprise. I'm not using reprojection in either case since I grew quite tired of the artifacts. I'm using a Reverb G2 at 60Hz.

The higher headtracking latency mentioned earlier makes sense. I don't know where to look for that statistic myself though.

Edit: The OpenXR Toolkit "Turbo mode" is coming to my mind. I may try again disabling it.

Edit2: It was already disabled...

I dont quite understand VR tech yet, but I wonder:

Maybe DCS OpenXR somehow forced in its own kind of motion reprojection, and works off bugged motion vectors? Its not so bad with plane movement, but head movement causes massive issues, like some crazy overshoot. Also performance problems.

Im running a Pico 4, which uses different software and relies on streaming, but we seem to have similar issues.

Edited March 17, 2023 by Temetre

[average_pilot]

On 3/17/2023 at 2:30 PM, Temetre said:

I dont quite understand VR tech yet, but I wonder:

Maybe DCS OpenXR somehow forced in its own kind of motion reprojection, and works off bugged motion vectors? Its not so bad with plane movement, but head movement causes massive issues, like some crazy overshoot. Also performance problems.

Im running a Pico 4, which uses different software and relies on streaming, but we seem to have similar issues.

 

I'm not sure anymore, I may have been imagining things or the last patch made things better. Furthermore, Turbo Mode (from OpenXR Toolkit) actually helps A LOT. Also I reduced VR resolution to 45% and I get barely any stutter at all, fps are so stable now that it's starting to feel like actual virtual reality... I mean, for 60Hz refresh rate and lowish resolution.