Performance Issues with F-15E in VR - Radar causing this?

[MIghtymoo]

Hello fellow pilots,

Is anyone else experiencing performance issues with the F-15E in VR? I’ve noticed massive frame drops and stutters when flying the F-15E, even on maps like Nevada. My frame rate often drops as low as 18fps, making it feel like a slideshow.

Interestingly, when I run an identical mission with the F-16C, the performance is super smooth. I even added 8 full SA-10 sites to Las Vegas area in the F-16 test mission to give the CPU some extra load, but it still performs flawlessly (when F-16 is invincible and being hammered by multiple SA-10 launches).

Could there be an issue related to the radar system in the F-15E causing this performance drop? Any insights or solutions would be greatly appreciated.

Fly safe!

UPDATE: SOLVED WITH DCS UPDATE DCS 2.9.3.51704 (22. February 2024).

Edited February 24 by MIghtymoo

[WizzRD]

Check if you have Civilian Traffic enbled and if you do try disabling it.

Helped me getting rid of the stutters.

[draconus]

In DCS options > special > F-15E you can test different values for cores used for radar simulation.

[jaylw314]

Running smoothly with a 4080, I've only seen fps drops when I first turn on the AG Radar to longer ranges.  If I turn it on at 160 nm, fps will drop for about 5-10 seconds, but then it will return to normal and doesn't happen again, so my experience has been the AG radar issue is not a continuous problem

[MIghtymoo]

Civilian traffic off, mirrors off, no mods installed. All other modules run well. Have repaired DCS and no help. 

May try to reinstall the F-15E.

Edited February 13 by MIghtymoo

[chichowalker]

For me is exactly the same. Now is not flyable in VR. Upon entering in the cockpit performance blows up. Other aircraft are very smooth, including Apache right now but since 2 or 3 patches ago, for me strike eagle is a no go. No matter what I choose, low GPU textures or increase cores for radar. A lot of strutters appears when I try to fly this aircraft.

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[Ramstein]

On 2/16/2024 at 9:22 AM, chichowalker said:

For me is exactly the same. Now is not flyable in VR. Upon entering in the cockpit performance blows up. Other aircraft are very smooth, including Apache right now but since 2 or 3 patches ago, for me strike eagle is a no go. No matter what I choose, low GPU textures or increase cores for radar. A lot of strutters appears when I try to fly this aircraft.

Enviado desde mi SM-G981B mediante Tapatalk
 

I got mine with the F-15E going pretty good, my issue is my old video card... in VR it really needs a lot of computer power. I posted a writeup recently of settings I use.  I can try and find it and point others to it, if they have Oculus VR.  

 

Edited February 18 by Ramstein

[chichowalker]

It looks like VRAM problem. When I Alt+tab and open internet Explorer for instance, then I come back to DCS and again 72 fps in the cockpit. One minute after, again 20 fps...
I have flown 2 liberation campaigns previously in F15E without problems but now it's imposible .


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[draconus]

11 hours ago, chichowalker said:

It looks like VRAM problem.

Then do a test with both texture settings on low/medium plus the older GPU setting in special > F-15E.

On 2/18/2024 at 8:56 AM, Ramstein said:

my issue is my old video card

It may be older but still on the 3070/4060TI level.

[Ramstein]

I can get a 40 to 80 fps.... in vr,, that's not the issue, I said that the controls in the switch from a-g to a-a modes, the radar screen loses the ability to be control once ina while, like some key press causes causes radar controls to jam and not be fixable without getting another aircraft.

[chichowalker]

Already tested with Low_GPU textures and same results. My GPU is RTX 3080 Ti.

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[Raven (Elysian Angel)]

On 2/16/2024 at 6:22 PM, chichowalker said:

Upon entering in the cockpit performance blows up.

Are you using MSAA? Disable it if so: it is ridiculously VRAM demanding.

You also might want to play around with preload radius to see what works best for you.

[chichowalker]

Are you using MSAA? Disable it if so: it is ridiculously VRAM demanding.
You also might want to play around with preload radius to see what works best for you.

Negative.
I use no upscaling with DLAA only.

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[Raven (Elysian Angel)]

4 hours ago, chichowalker said:

Negative.
I use no upscaling with DLAA only.

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The framerate window when pressed a 2nd time displays more detailed information including VRAM usage.
For reference, I don't use any upscaling/AA and on newer maps 11 to 12GB of VRAM is in use on my system, so I have some headroom available.

[chichowalker]

I use to monitor VRAM load with OpenXR Toolkit overlay and always is below 100%. 

[Nealius]

Is this after using AG radar? I have discovered that leaving AG radar as SOI before switching the display to a different page allows the radar to continue making patch maps in the background, and this causes fps issues over time. If I de-SOI the AG radar my fps comes back.

[chichowalker]

Negative. Just in ground before taxi with Radar off or stby. Or in flight with radar in AA

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[eFirehawk]

I can report the same... on high settings I get mostly uninterrupted 72fps since the last patch with all jets that I fly relatively regularly except the SE, which makes the fps on average 15fps lower... which is a shame since it's my favorite jet and the best DCS module so far in my opinion.

[BenPR1]

I turned everything to low or off, using dlss, Special Menu (low gpu, tried thread 2 to 12). Getting 40 to 50 fps. BUT the AA RADAR cursor still ghosting and sluggish when slewing...run out of option to fix AA Radar ..

I do have a RTX 2070, 32g ram laptop, but F18,16 even F14 runs fine even at higher med setting..

 

[draconus]

1 hour ago, BenPR1 said:

AA RADAR cursor still ghosting

This is caused by DLSS or other Temproal type AA. Try MSAA.

[BenPR1]

I tried, same issue, MSAA have even lower fps. I think F15E and Apache had outpace my 2070 laptop.

[Kercheiz]

If anyone still has non-HRM radar related performance issues, please notify us here. I'm having a look at this and already optimized it quite a lot internally.

To know if it's radar related, just check it's fully correlated with having the radar and/or TFR on. If setting radar and TFR to SBY does no instant improvement, means it's something else, like rendering.

[Raven (Elysian Angel)]

7 hours ago, Kercheiz said:

If anyone still has non-HRM radar related performance issues, please notify us here.

Well, what I notice is that the frame graph (the default DCS one) has a lot more "sawtooth"-behaviour than other modules, if that makes sense (very high frequency up-and-down jumping of the frame times but with limited amplitude difference - so the framerate doesn't change that much but the changes are very rapid). This makes flying the F-15E 'feel' more stutter-y. And this is indeed with radar and TFR on standby.
What the cause of that is, I do not know.

P.S. I could try making a screenshot if that would convey it any clearer than what I wrote above, but it would be in VR.

[Kercheiz]

Radar and TFR on standby, means it's most likely a 3D rendering bottleneck. The F-15E is quite detailed.

[Raven (Elysian Angel)]

It sure is. If that bottleneck can be alleviated with Vulkan there is nothing to worry about, we’ll just have to be patient.

If it can’t, I hope RAZBAM finds a solution.