RealDCSpilot

@Gunnars Driver This also maybe interesting for you.

@propeler Nice! Please inform me when i can order one device from you. :)

@f4l0 Just a tiny setback. If i choose the P47D-30 early version first i still get the script error. But if i choose the D-40 before that and switch to the D-30 the issue doesn't occur.

@walmis Wow, great!!! What a monster! @propeler and walmis What do you use for axis sensors?

It's just a simple guess, yes or no will be enough.

@Stal2k Would you mind to do another test? DCS is always a bit behind with the latest version of the openvr.api. Currently it uses version 1.0.10.0 while the official api is at 1.14.15.0. You can download the latest version here: https://github.com/ValveSoftware/openvr/blob/master/bin/win64/openvr_api.dll Just place it under \DCS_World\bin and backup the old file. This should rule out any incompability issues with the latest version of SteamVR. Maybe it is a bit more bulletproof in stress situations, maybe not.

Okay, now we get closer to the source of a misunderstanding. Please excuse my english, i have to translate everything and it's hard to be exactly precise sometimes. I have to make this guess here, the source of the problem isn't a bad line of code causing an illegal function call somewhere that leads to a crash, it's definitely not that kind of bug. You will never find a step by step procedure to nail it down with 100% certainty that a certain action caused the problem. To be affected by the problem you actually have to play the game in the field. Online, in free for all sandbox missions with other players. If you don't know what the "Through the inferno" missions are, than you seem to play DCS in a different way. I took a look into your mission and found a huge amount of units, yes, but also a lack of variety. Example, having 200 units of the exact same type will make no big difference in VRAM usage. It will just use the amount a single unit of that type needs. You will probably never really run into a problem if you just play DCS in "linear" type of missions, were you basically choose one aircraft, do your mission, finish it and the mission is over. Missions like "Through the inferno" are very popular online, because you can join them and do whatever you want. All the variety that DCS is providing is available there, you can choose every module, use every weapon. You can choose to train carrier landings in a F14, another group of players in A-10s is attacking an enemy airbase over 100km away, while on the other end of the map a player tries slingloading containers with a helicopter. These kind of missions are usually named "...freeflight...", "...training...", "free for all...PVE" etc. A typical online session can take 30 minutes or 4 hours, including switching to all sorts of modules, from jet to helicopter to WW2 aircraft. The server itself will always run 24/7. In these missions the problem is very common for some of us, it can happen after 10 minutes or after an hour. If you are lucky, you only get the frame drop problem for 5 or 10 minutes and it sorts itself out after a while. But since a couple of weeks, Steam VR crashes occur more often and it's not a new problem: https://forums.eagle.ru/showpost.php?p=4379001&postcount=3 It really looks like a problem of bad or incomplete memory management. Instead of clearing memory resources after i choose another jet, DCS just stuffs the next jet's textures and geometry into VRAM and then the next one and the next one until VRAM is full and then memory swapping starts, trying to sort it out somehow. Sometimes Steam VR is the weakest part in this, and crashes. The only way to prevent the problem to occur seems to be having a GPU with lots of VRAM, since i got my RTX3090 the problem never ever happened again on my end. DCS now uses a huge chunk of it, up to 17/18 GB.

That's exactly whats going on. Simply switching to another aircraft just adds data to VRAM without purging the unnecessary data from the former aircraft.

Back from the depths of the forum: https://forums.eagle.ru/showthread.php?t=236834

@f4l0 Thanks! That was fast. Tested all variants and it works now.

+1 This is simply the best analogy i've read on that matter. A complete other point is, if you are paying FB for the HMD itself any money, you are a fool. It's like paying a vampire's dentist to make sure he can put his teeth into you, the best way possible to drink your blood. They claim that it is subsidized, that they loose money selling it at this "low" pricing. The truth is, they will earn multiple times the money over the years from the data you will provide. If you are really willing to do that, the HMD should be free. Look at their revenue just for the 2nd quarter of this year: https://www.statista.com/statistics/422035/facebooks-quarterly-global-revenue/ It's crazy how much money the business with personal data is able to generate and you are paying on top of it to put a parasite on your forehead.

@f4l0 The new stable version 2.1.0 still triggers a script error for the new variants of the P-47D (30 late and early version, new 40 version with new rocket pods).

Before we start banging our heads against the walls... @Pikey You already were in the zone for the problem in your video at 6:41 in your mission. At this point, when the sudden framedrop occurs, the chances are high SteamVR can fail. It's kind of a precursor for the crash. Usually, in the same situation, an action like switching to the F-14 on the super carrier and using F10 map after that triggers it.

@Pikey Hi mum, try to ... ;) Use the ingame settings i posted under 1.a) set all on "high". Choose maybe 170% SS in Steam VR - it's all about provoking the issue. Just look for a multiplayer server with almost all modules included. It's not depending on a specific mission! Public Training servers hosting the Syria map, like from "Havoc", "Kirk's Hangar" just to name a few. They all have a certain amount of ground vehicle activity, all modules available including the supercarrier plus tankers and AWACS in the air. If the framerate starts to drop like in the 6th minute of your video, you are almost there. One of the next attempts to switch to another aircraft or the F10 map might trigger SteamVR (and it's WMR plugin) to fail again.

For me it's running the game at 2x 2880x3200 pixels, 4x MSAA and extreme visibility range. Looks fantastic and no doubt this will work great on any future VR HMD with higher resolution panels than the current gen.

I can't trigger this issue anymore because my GPU now has 24GB VRAM. I already had 64GB RAM before i upgraded from a 2080ti with 11GB VRAM. So VRAM needs to be watched closely, it's the only factor that changed on my end. Steps to reproduce were: 1. a) use high settings that demand more VRAM (textures high, terrain textures high, water high, vibility range high, heatblur low or high ...) b) raise SteamVR render resolution between 150%-200%, ingame PD setting at 1.0 at all times (somewhere is the sweetspot for your system, restart is always required to apply changes) c) having a bunch of other windows open will also help slightly raising VRAM usage (discord, simshaker ...) 2. choose a server with a big mission like TTI on Syria 3. choose any aircraft, jump to cockpit, choose next aircraft (F/A-18 or F-14 on supercarrier to have the biggest impact), jump into cockpit, check external views, switch to F10 map, switch back to cockpit, switch to F4 external view of other aircraft a couple of times. 4. repeat step 3 and at some point SteamVR should crash. The more different modules you own/can to jump into, the better...

@VirusAM I have a Valve Index and had a 2080ti before, had the sudden frame drop issue and occasional SteamVR crashes over the last couple of patches since the introduction of the Syria map. But i was also always driving the limits of highest possible visual quality settings the whole time and knew that will cause issues. DCS isn't a normal game however, most games are designed to fit in a certain spec range of hardware. DCS just uses everything it get's, the need for 32GB of RAM for instance is quite unusual. But on the other hand, it wasn't designed for highend VR in the first place.

@Pikey Good video with lot's of important information. The only thing that's missing are your exact system specs and DCS settings. What i can clearly see before the 6th minute, your system resources are about to collapse. Your VRAM (8GB) and RAM (32GB) usage is maxed out already, all it needed was to switch back to the cockpit and that was the last drop. Your HD started to try to swap memory from the pagefile back and forth, trying to manage the overflow of RAM and VRAM simultaneously, because there isn't enough memory left in RAM and VRAM. It starts to bite it's tail here, VRAM is full - the system wants to use RAM for sharing video memory, but RAM is already full and starts to make more use of the pagefile on disk. Every I/O is at full load and starts to chase another problem. In certain cases, Steam VR's own part of allocated VRAM seems to fail there, because no resources are left. Edit: ok, just watched more of the video and saw the ingame settings... They are already pretty low. If you would go higher, you should be able to trigger the problem earlier. Atm, only more RAM and VRAM seems to help there.

@FoxTwo Try these settings to push over your VRAM limit. This is basically the highest visual quality for VR that you can achieve with a crowbar and the 3090 just eats it without complaining. It's 18.4m pixels with max settings on nearly everything. https://forums.eagle.ru/showpost.php?p=4524203&postcount=57

@Taz1004 Read again, don't twist what i wrote. I was measuring the whole windows desktop taking 1.4GB VRAM on a ultrawide monitor. Every new window aka "running app" on the desktop, takes a bit more VRAM for the Desktop's screenbuffer. That's how Windows GUI works. Every new opened window needs VRAM to get it's content displayed, because it's a 2D plane with graphical elements which need pixels to be drawn and stored somewhere. It doesn't cost "performance" but it needs resources like VRAM. The more windows aka "apps" are open the less VRAM is left for the game. It's a couple of hundred MB per window on a high resolution monitor. The need for a bigger rendered frame to counter lens distortion is common VR technology for every headset:

Don't forget that this is running more than 4K resolution for each eye. Given that, it's a pretty normal VRAM usage. Running the game on just one 4K display should be a bit under 10/11GB in all situations.

https://www.bradford.ac.uk/t4-ssis/ruski-files/academic-voice/page_07.htm Please provide evidence then. Real information how stuff works and how it matches your posts.

Yeah, like you tried to explain to me in another thread, that Windows, mirroring a screen directly from the front-buffer of the GPU to a second monitor is exactly the same like the extra VR mirror window on the desktop while having VR running. And that this extra window doesn't need extra VRAM to be rendered on the desktop. (Well it does, because it's copied from the VR screen buffer and stored in the front-buffer for the monitor, of course this takes extra space in VRAM. If more windows are open, the more information needs to be stored in the front-buffer)

Goodness... 1. Reverb owners have to use the Windows Mixed Reality plugin for SteamVR. The plugin handles all the necessary api requests first before Steam VR handles the rest. A reverb user will only see the end result, that's why it shows their native resolution at 100% in Steam VR. 2. There is always the need to postprocess lens distortion for a flat frame from a game camera for any kind of VR HMD. Therefore you always need more pixels in a rectangular frame that will be lost during this operation because of the lens matched distortion. This is a basic VR process to display a flat picture on a flat panel that is only being watched through convex lesnes. 3. The PD value in DCS acts as an override in combination with SteamVR. The openVR api asks the game to render a given resolution, but DCS returns a much higher resolution frame if the PD value is higher than 1.0. This is wasting frametime, because it obviously won't fit and needs to be resampled. Letting SteamVR managing resolution and supersampling instead is the much more efficient way. It also has an extra option of an advanced supersample filter under Video Settings. Why don't you test this for yourself? Try to set a PD of 0.5 in DCS and look what happens. The result will be a super blocky low res image, but still supersampled to a high resolution frame with your settings in SteamVR 100% 150% whatsoever... The difference might be if DCS is using the oculus api, here the PD value seems to hook directly into it. I can't test this here. SteamVR and it's openVR api is a image/pixel processing engine. The word "render" can be widely interpreted here. Just a simplified explanation from the api documentation: "One real-world example of an application is a game engine like Unity. Unity calls OpenVR API to get the position and orientation of any attached VR headset and apply them to the Main Camera. Unity then sends the camera image to OpenVR. OpenVR does some operations on the image and then displays it to the real headset screen." Call it what you want...

Don't forget all the other hardware involved. Makes more than 6000 or 7000 quids for the highend experience? :pilotfly: No need for exaggerations if there is enough money to throw at the problems. ;)