Poor performance with VR in general!

[DeTesla]

Let me just state for the record im running MT, on a Quest 3.

After how many years since DCS implemented VR, and subsequent the time since the Apache got released, the performance in VR while flying the Apache is absolutely, rightly said, <profanity>!

And i suspect i know why; DCS, the whole client, even after the multithreading rewrite, is just spagetti code, add to that the Apache LoD models which dont seem to really work well.
Code wise, doubtful ED will fix any of that because that entails a whole new rewrite of DCS codebase.

But, i digress.

Running DCS in VR on a medium specced PC should atleast run semi smoothly depending on the settings but for most of us actually, that is not the problem, so in the end collectively VR users need to limit the VR experience to get a modicum of FPS performance, which requires a ton of tweaking. And even with the tweaking, DCS even has GPU memory leaks which has gone unaddressed for years. I also suspect this is because of the spagetti code which noone will touch with a 10 foot pole!

This is not favorable for newbies who want to utilize DCS in VR.

Actually, this is not favorable for any of us who utilize DCS in VR.

So i reckon ED has shot themselves in the foot by implementing VR, on a codebase which stems from as early as LockOn, which by now is a simmering pot of pasta bologna and well cooked spagetti, all intertwined with eachother which by now, realistically untangling it, is economically unsound at best.

So this is basically why we all have performance issues in VR. And it is by far the most un-optimized game with VR compatibility i have ever come across in all my years owning a VR headset on account on how long VR has been available to DCS.

My current performance in the Apache after some 30 minutes passed on my Quest 3

Personally ive tried to optimize and get more performance with the tray tool and nvidia 3d settings, but with DCS constant GPU memory leaks, especially F10 map which i really hesitate to press, i am out of logical ideas so if any of you has any suggestions i'd love to hear them, extremely much!

 

Memory leak continued even after going back to the menu, which is undeniable to be a memory leak.

Edited May 23, 2024 by DeTesla
Removed Problems with Apache. Added Problems with VR in general.

[Dangerzone]

I agree with you that the Apache certainly takes more GPU than other birds, I don't believe DCS has shot themselves in the foot with VR. In fact, it's VR that has captured me. I have concerns about the new modeling of under the panels in regards to whether that is going to impact on more resources or not. 

I accepted some time ago, that if I want good VR experience, I need to shell out and buy the top of the line hardware, so I purchased a 4090. That hurt the hip pocket, and I'm well aware that there are others that can't afford to do this. However I did run VR with a 2080Super for a few years before that, and that worked well back with DCS 2.6, and 2.7. It was only with more recent updates that I started getting to a point where I knew I had to update. Then... I updated to the 4090 just before DLAA/DLSS was implemented, so I never got to experience just how much of an improvement that would have made. 

There are definitely compromises when going to VR. However, I've flown MSFS in VR a number of times, and honestly, I don't see DCS being that bad in comparison. (I'm aware YMMV, but my experience on both my 2080S and my 4090 is that DCS is doing OK at holding their own in VR against MSFS). 

ED are being active. They implemented DLAA/DLSS, and are working on Vulkan. I know the wheels turn slow, and I know it's disappointing to have to wait so long. But fact is, if VR wasn't available in DCS, I'd probably walk away now (and I think there are many others that use VR that would too). I fail to see how they've 'shot themselves in the foot' by giving us options. If people don't think DCS should have implemented VR - they still have the option to fly 2D, so I disagree there. 

This isn't to say their can't be improvements. The F10 memory leaks are indeed a concern. Being a Dev, I know how damn difficult it can be though to track down those memory leaks too, and have sympathy for the dev's that are trying to find them. Thankfully I have not experienced F10 issues since getting the 4090. It's a pitty that NVIDIA didn't throw more RAM at the 4080. (I think I read the other day someone mod'd the 4070 with more RAM and it outperformed the 4080). 

Hopefully they are able to identify the memory leaks soon, or Vulkan is closer than it seems and it brings some much needed solutions to the table. 

[ETBSmorgan]

Texture-> default 

No difference and better fps, you can also use the mod for cockpit in low resolution, no visual difference and again better fps.

Thanks the M4 in 4k....

 

With the quest3 I use virtual desktop, better experience.

[LOW_Hitman]

vor 8 Minuten schrieb ETBSmorgan:

Texture-> default 

No difference and better fps, you can also use the mod for cockpit in low resolution, no visual difference and again better fps.

Thanks the M4 in 4k....

 

With the quest3 I use virtual desktop, better experience.

Which textures do you mean? Ground, Cockpit? Because having the cockpit textures lower than high makes them unreadable in VR

Edited May 23, 2024 by LOW_Hitman

[ETBSmorgan]

4 minutes ago, LOW_Hitman said:

Which textures do you mean? Ground, Cockpit? Because having the cockpit textures lower than high makes them unreadable in VR

 

Cockpit and I can read .

[Dangerzone]

I haven't tried low cockpit textures in the AH64. I don't use low because in the UH-1 - the textures really are unreadable. They're a blotted mark at best, and as I fly multiple airframes I opted to keep away from low cockpit textures. That being said, there are 3rd party cockpit textures you can load into the saves games directory and I have used these before. Maybe that's why I'm not getting the hit that some others are?

[LOW_Hitman]

vor 58 Minuten schrieb ETBSmorgan:

Cockpit and I can read .

Left side low textures vs right side high textures. Please don't tell someone that there is "no difference in quality"

Edited May 23, 2024 by LOW_Hitman

[Johnny Dioxin]

I'm honestly really surprised to come across this thread this morning. When I bought the Apache I couldn't use it because it was such a slideshow. I tried it again last year and it was better, though still a bit problematic under certain circumstances.

Last night I had a go again in my Pico 4 using Virtual Desktop and OpenXR with MT and it was solid. 90fps - and I kept the in-sim fps displaying during start-up at a busy aerodrome, which usually means half rates. I did notice my GPU fans were busy a lot of the time, but it may just be cos we're starting getting warmer weather here. Actual temps according to GPU-Z didn't rise above 64°C.

It was a bit frustratingly slow to load up the textures, but I could say that about a few modules. Also frustrating that it then doesn't use the full capacity of my RAM and VRAM, but I'm not techinically minded enough these days to understand why that is. Might be a perfectly viable reason for it. Once the textures were loaded all was great and as readable as always.

But VR performance-wise I was very impressed.

 

*unfortunately I didn't take any screenshots, which I usually do.

Edited May 23, 2024 by Johnny Dioxin

[ETBSmorgan]

1 hour ago, LOW_Hitman said:

Left side low textures vs right side high textures. Please don't tell someone that there is "no difference in quality"

 

On the ah64

[DeTesla]

I hear you, absolutely.

But if DCS' memory leaks are so bad for some people with medium hardware that even in the menu after leaving a server FPS drops to 10 and below and stays there for several minutes, then DCS has some serious issues that has gone unmentioned for a decade or so.

I understand that ED is creating vulkan rendering system, and that is all good and nice and all, but damn if DCS runs so poorly on VR as it does now then vulkan rendering have to rewrite alot of the DCS spagetti code. If they just slap vulkan over the DCS core and call it a day, that wont fix anything, hopefully they dont do that.

Ive gone through and tested alot of different configurations with oculus tray tool and OpenXR toolkit, combined with DCS graphic settings, and im getting nowhere. I even lowered nearly everything and restricted POV to less than 65 just to test, and its still bad, with alot of stuttering, with max FPS of around 30-35.

I'm sorry, but right now as DCS stands today, it is absolutely not worth flying in it in VR. It is by far the worse VR experience ive had to date in a game.

EDIT; I monitored my hardware status during this, and my VRAM was maxing out all the time. CPU was around 25-30% and used only around 50% of my RAM capability.

I understand that the GPU is a major player when it comes to DCS, but if the game maxes out its capabilities all the time with no headroom at all, even when back in the menu, then i really dont think my GPU is the problem. What ED should really do is address the apparent memory leaks when running the game in VR.

Bignewy you can chip in at any time concerning this. I know the all-seeing eye watches all!

Edited May 23, 2024 by DeTesla

[Glide]

These settings are for my 3080Ti and Pimax Crystal.  72hz fresh rate.  I believe these settings are ideal.

I run the headset at Maximum resolution with Dynamic Foveated Rendering enabled in the headset.  No Smart Smoothing, so no ASW.

Nothing in the Nvidia control panel.  No Low latency mode at all.  Restore defaults and forget about them.

No Quadviews.  No frame locks, no refresh rate locks.  HAGS on, and windows Flip Mode Enabled in Windows 11.

Turbo Mode on, or Prefer Frame Rate over Latency enabled in PimaxXR companion. 

The goal here is to be GPU bound.  You want to add work for the GPU without exceeding your VRAM limit.

I get around 50fps with this setup.  I never see any desyncs.  It is incredibly smooth.

Use the OpenXR Toolkit FPS counter on Advanced to tune your VRAM limit and get app GPU frame times around 20ms.

Just so you know what I'm on about here, with an app GPU time of 20ms, the GPU is controlling the pace of the entire pipeline. Try this on Marianas with Overcast and Rain in the TF51D.  I get about 30fps in that scenario, but it's a very stable 30fps.  You can vary the ground details (grass, forest, etc.) as desired.

Edited May 25, 2024 by Glide