Fps tank when changing aircraft or server

[Spetz]

It’s happens to me too. On Syria map, no mods, in VR, start in the Hornet with 45 FPS, switch slot to Viper, FPS down to 24ish, then switch to anything else, FPS tanks to about 8.

 

Sometimes exiting that mission and loading up something in the Caucasus brings it back, but more often than not, have to fully exit the game and get back in.

Edited January 28, 2022 by Spetz

[Sleepy Joe]

5 hours ago, Spetz said:

It’s happens to me too. On Syria map, no mods, in VR, start in the Hornet with 45 FPS, switch slot to Viper, FPS down to 24ish, then switch to anything else, FPS tanks to about 8.

 

Sometimes exiting that mission and loading up something in the Caucasus brings it back, but more often than not, have to fully exit the game and get back in.

 

Alt Tab out of the game until your FPS stabilizes. It can take upwards of 30 seconds sometimes but 95% of the time it fixes it for me.

[edmuss]

Not sure if it's directly related but I suspect it is, I was suffering from frame drops when re-flying a mission or changing to a different map without restarting DCS. The alt tab trick would usually settle it down as mentioned above but not all the time.

Turning HAGS back on fixed it for me and I've not had the issue since, no other side effects otherwise.

[Eviscerador]

I have the same issue but I found a workaround to fix the issue quickly every time it happens.

All you need to do is alt tab DCS, click on the WMR window and then return focus to DCS window with mouse.

It fixes the issue and your DPS will get back to normal without having to restart DCS, WMR or even leaving the server.

Dunno why it works but it does for me. It is clearly some software issue.

[Wizard1393]

I've got this issue aswell since 2.7.

[hazzer]

Hi all, comically I was just searching to see if I could find a fix for this issue... and found my own thread. 

Just wondering if anyone found a magic band aid for this?

[edmuss]

Running openxr has eliminated it almost entirely, it's much better on VRAM than steamvr is

[hazzer]

22 hours ago, edmuss said:

Running openxr has eliminated it almost entirely, it's much better on VRAM than steamvr is

Thanks for the info! Is there anything I need to do to run openxr? 

[edmuss]

2 minutes ago, hazzer said:

Thanks for the info! Is there anything I need to do to run openxr? 

The ability to read and follow instructions

Check the openxr thread

[DuRiN]

Same issue here, some times recover normal fps with alt+tab and others dont recover....i have Quest 2 but have Valve Iindex too...with Valve Index i have no problem but i choose to fly with Q2 for image quality....

[zvina]

I’m not spending a single cent on DCS anymore until this gets resolved as it is very annoying. 
 

12700K

3070ti

quest 2

 

everything just like others pointed out. And I don’t even need to switch aircraft, it’s enough to be in a somewhat busy server and it’s unplayable.

[edmuss]

On 8/23/2022 at 1:33 AM, zvina said:

I’m not spending a single cent on DCS anymore until this gets resolved as it is very annoying. 
 

12700K

3070ti

quest 2

 

everything just like others pointed out. And I don’t even need to switch aircraft, it’s enough to be in a somewhat busy server and it’s unplayable.

The next release of the openxr runtimes from Microsoft should fix the problem when running openxr.

It's linked to DCS not leaving enough VRAM for reprojection to work. The new runtimes pre-allocate a block of VRAM specifically for the reprojection and this has fixed the issue for me entirely. I am running with a test dll from the devs to prove the function.

When running reprojection I now no longer have performance tanks to 15fps on mission restarts or slot choices, neither does it randomly drop

[Dangerzone]

15 hours ago, edmuss said:

The next release of the openxr runtimes from Microsoft should fix the problem when running openxr.

It's linked to DCS not leaving enough VRAM for reprojection to work. The new runtimes pre-allocate a block of VRAM specifically for the reprojection and this has fixed the issue for me entirely. I am running with a test dll from the devs to prove the function.

When running reprojection I now no longer have performance tanks to 15fps on mission restarts or slot choices, neither does it randomly drop

This is fantastic news. Thanks edmuss. Is this something that will just automatically update for us, or that we specifically need to install?

[edmuss]

4 hours ago, Dangerzone said:

This is fantastic news. Thanks edmuss. Is this something that will just automatically update for us, or that we specifically need to install?

It should be automatic assuming you have use latest openxr preview enabled on the openxr tools desktop app (I think!).

The current release is 111, it should be updated for 112 shortly hopefully

[Dangerzone]

1 hour ago, edmuss said:

It should be automatic assuming you have use latest openxr preview enabled on the openxr tools desktop app (I think!).

The current release is 111, it should be updated for 112 shortly hopefully

Wonderful - thanks for the confirmation. I eagerly await 112.

[winghunter]

I still have this issue with WMR 112.2211.2002 and 2.7 or 2.8

Edited January 2, 2023 by winghunter

[winghunter]

Ok finally resolved it:

Turned HAGS on - no effect

cleared WMR environment - no effect but probably good idea regardless

Turned OpenXR MR from ON to AUTO - no effect but probably good idea regardless

Turned OpenXR Toolkit framecounter off : There you go this thing cost me like 30% in frames. I was actually laughing hard when i realised this.

 

I use the fps counter open from OpenXR DevTools now.

 

Now i can open the same mission 3 times in a row with consistent frame rates without having to restart DCS

 

Edited January 2, 2023 by winghunter

[Flappie]

Thanks for your feedback!

[winghunter]

I've filed a bug with OpenXR toolkit. The developer says the frame drop is expected, there is no way around it. Just something to be aware of when using the OpenXR Toolkit overlay.

[edmuss]

6 hours ago, winghunter said:

Ok finally resolved it:

Turned HAGS on - no effect

cleared WMR environment - no effect but probably good idea regardless

Turned OpenXR MR from ON to AUTO - no effect but probably good idea regardless

Turned OpenXR Toolkit framecounter off : There you go this thing cost me like 30% in frames. I was actually laughing hard when i realised this.

 

I use the fps counter open from OpenXR DevTools now.

 

Now i can open the same mission 3 times in a row with consistent frame rates without having to restart DCS

 

 

What you've done is disabled reprojection, the auto option only applies to msfs and with any other app turns out off.

The reprojection framerate tanking bug was eliminated from toolkit version 112 onwards. Make sure you have the latest version

[winghunter]

1 minute ago, edmuss said:

What you've done is disabled reprojection, the auto option only applies to msfs and with any other app turns out off.

The reprojection framerate tanking bug was eliminated from toolkit version 112 onwards. Make sure you have the latest version

I have toolkit v1.2.3 and still got this issue. I was pretty sure MR is still enabled ingame hmm let me check

Edited January 2, 2023 by winghunter

[winghunter]

You are right, MR was disabled. It just felt so smooth after testing with low frame rates for hours that i thought it was still enabled.

Im almost back to square one, with MR enabled i still get the framerate tanks after repeatedly starting a mission. At least disabling the OpenXR toolkit FPS overlay improved the framerates overall. And now i know its related to MR and not DCS or HAGS

[edmuss]

I'd try uninstalling the toolkit and reinstalling fresh.

[winghunter]

I have de- and re-installed OpenXR runtime, OpenXR devtools, OpenXR Toolkit, but the problem remains.

( Disabled HAGS again, made no difference to enable it for the mission reload problem and most people get more stutters with HAGS on. )

I figured out its a combination of things relating to VRAM on my 3070 (8gb)

 

edit:

green: my regular fps for this mission
red: significant drop in fps 10% or more

Terrain textures high, MR off:
First mission: framerate green
Mission reload: framerate green

Terrain textures low, MR off:
First mission: framerate green
Mission reload: framerate green

Terrain textures low, MR on:
First mission: framerate green
Mission reload: framerate green

Terrain textures high, MR on:
First mission: framerate green
Mission reload: framerate red

So it seems that having both: terrain textures HIGH and MR enabled is too much for the VRAM to handle, which then gets worse every time a mission loads. This is possibly due to VRAM being outsourced to RAM. From what i read there is no way to disable shared memory, so the GPU will always offload to RAM if VRAM is full.

 

Edited January 2, 2023 by winghunter

[edmuss]

Simply going by the colour of the WMR overlay means that you're above or below refresh rate. If you're reprojecting then it's blue, interesting that you're not getting any of that? Look at the appCPU and appGPU frametimes, also the postGPU (which is partly the overhead caused by reprojection).

I found with my 3070 high textures would show things down but not cause a crash due to lack of VRAM. What was found with the toolkit was that DCS would aggressively allocate VRAM which inadvertently withheld it from the reprojection. This still happens with steamvr and possibly oculus as well but was eliminated with the toolkit by earmarking a portion of VRAM for reprojection alone.

What resolution and refresh rate are your using?