Massive FPS drop with landing lighs

Any issues, problems or troubleshooting topics related to the Prepar3D client application.
Marek2704
Posts: 4
Joined: Sat Sep 28, 2013 10:31 pm

Massive FPS drop with landing lighs

Post by Marek2704 »

Electra A10 suffer massive, about 20-30 FPS drop when landing or taxi lights are turned on. Chcecked with 29Palms Samos and one of default airports.
CTVredvirus
Posts: 213
Joined: Thu Sep 19, 2013 7:54 pm

Re: Massive FPS drop with landing lighs

Post by CTVredvirus »

Have the same issue, maybe more can thest this so LM finds a fix not only with electra , I have tested the F22 and I think all of those planes have this issue
OCZ 1250W, Asus Maximus X formula, Intel 8086k, 32GB Ram, RTX 2080.
P3D addons: PMDG 737ngx, 777, 747, 737ngxuORBX Global, eurpoe, vector and ESSA, AS, FS2CREW, UT LIVE, P3Dv4 and 5. CLS-E MK II RUDDER WITH TOE BRAKES & CLS-E MK II BUNDLE
CTVredvirus
Posts: 213
Joined: Thu Sep 19, 2013 7:54 pm

Re: Massive FPS drop with landing lighs

Post by CTVredvirus »

Marek2704 wrote: Wed May 31, 2017 3:54 pm Electra A10 suffer massive, about 20-30 FPS drop when landing or taxi lights are turned on. Chcecked with 29Palms Samos and one of default airports.
OK the problem is dynamic lighting when its enabled that hapens, whe it is of the frames are ok
OCZ 1250W, Asus Maximus X formula, Intel 8086k, 32GB Ram, RTX 2080.
P3D addons: PMDG 737ngx, 777, 747, 737ngxuORBX Global, eurpoe, vector and ESSA, AS, FS2CREW, UT LIVE, P3Dv4 and 5. CLS-E MK II RUDDER WITH TOE BRAKES & CLS-E MK II BUNDLE
cassis87
Posts: 14
Joined: Sun Feb 12, 2012 4:48 pm

Re: Massive FPS drop with landing lighs

Post by cassis87 »

Indeed the dynamic lighting needs a fix.. from 70 to 15 fps at TNCM..
Wills
Posts: 207
Joined: Fri Dec 20, 2013 5:36 pm

Re: Massive FPS drop with landing lighs

Post by Wills »

What hardware are you using (specifically GPU and CPU)?
vmounier
Posts: 21
Joined: Sun Apr 12, 2015 4:47 pm

Re: Massive FPS drop with landing lighs

Post by vmounier »

Same here, depending on view (VC or outside) and direction (towards light or not), turning landing lights on, specifically in the PMDG 747, costs anywhere from 10 to 25 FPS. Worse at night of course.

I tried lowering the MAX_POINT_LIGHTS and MAX_SPOT_LIGHTS values but it eventually leads to VC lighting issues and doesn't appear to help. I think the brighter or bigger the light source, the worse it is, so the 747 with 4 landing lights has high impact. Other lights such as taxi or runway turn off have less effect unless combined. If service vehicles show up, we're down to a crawl.

Tested with MSAA and SSAA, the latter is worse of course but even MSAA suffers. 6700K at 4.8 Ghz, GTX 1080 at factory OC (running at 99% with aircraft stationary).
Vincent Mounier
User avatar
Scriptless
Posts: 21
Joined: Thu Aug 11, 2016 3:27 pm

Re: Massive FPS drop with landing lighs

Post by Scriptless »

Same problem here .. with PMDG 747 and default a/c.
With dynamic lighting on and landing lights turned on my fps decreases by 10-20 FPS.
Aiden327
Posts: 5
Joined: Sat Jun 03, 2017 1:22 pm

Re: Massive FPS drop with landing lighs

Post by Aiden327 »

I am also experiencing the same issue with the default bonanza. Seems when dynamic lighting is enabled, the landing and taxi lights cause a very significant FPS hit. I don't seem to be seeing an impact from scenery but I will do more testing.

Aiden
maca11
Posts: 143
Joined: Wed Nov 27, 2013 4:13 pm

Re: Massive FPS drop with landing lighs

Post by maca11 »

Same me.
The problem is dynamic lighting. Looks like it is an issue with GPU rather than CPU.
I have same FPSs with or without overclocking, however, GPU almost 100% once I switch on lights...(PMDG 747 but I gues it is very same with others...).
Any idea how to get back some usage from GPU to CPU ?
(sliders average, no other issues with performance other than lights....)

many thanks !
JM
Brad Shiver
Lockheed Martin
Posts: 361
Joined: Fri Mar 17, 2017 3:58 pm

Re: Massive FPS drop with landing lighs

Post by Brad Shiver »

Hi all,

Are you seeing this issue without any addons installed? What hardware are you using, specifically your graphics card?
maca11
Posts: 143
Joined: Wed Nov 27, 2013 4:13 pm

Re: Massive FPS drop with landing lighs

Post by maca11 »

Hi, my case
NVIDIA 1080 with newest driver.
having the drop in add-on airport (EHAM, fsdream charlotte-douglas) but the drop is also in default airports....
JM
Chri01
Posts: 2
Joined: Sun Aug 26, 2012 9:55 am

Re: Massive FPS drop with landing lighs

Post by Chri01 »

I'm seeing the same here with a Nvidia GTX 980. Dynamic lights seem to produce a massive performance hit on the GPU.
With locked frames at 36, dynamic lights on and 2xSSAA at a default airport with the Lockheed Electra at night I get

30 % GPU load with lights off
45 % GPU load with the taxi light on
65 % GPU load with taxi and landinglights on

So this means my GPU load more than doubles by just switching on two dynamic lights.
Anything higher than 2x SSAA and my GPU is at 100 % and fps go down.


Regards

Christian
Adam Breed
Lockheed Martin
Posts: 1382
Joined: Mon Sep 20, 2010 6:17 pm

Re: Massive FPS drop with landing lighs

Post by Adam Breed »

Hi All,

It will depend on your settings - it is known that SSAA does have a big impact with dynamic lights. Even with the best hardware the combination of the two can push the GPU to the max. Our algorithms are very efficient, but it is a lot to ask from even the best GPUs. We always will look for ways to improve performance moving forward, but you might have to experiment with settings to get the optimal level of performance you desire.

Regards,
Adam
Prepar3D® Engineering Project Manager
vmounier
Posts: 21
Joined: Sun Apr 12, 2015 4:47 pm

Re: Massive FPS drop with landing lighs

Post by vmounier »

As a follow-up, I've managed to deal with landing lights as they are usually needed far away from an airport's main light sources, but the fact remains that dynamic lighting for me is a pretty feature for future hardware but appears unusable at this stage, unless I am missing something. Sitting at a gate in KCLT in the 717 outside view, with no plane lights on other than nav, I go from 12 FPS with dynamic lighting on, to 36 FPS with it off, and from GPU at 99% to 76%.

Adam, tested at 2xSSAA and 4xMSAA, just about the same results. Can you confirm these changes do NOT require a sim restart to take effect? I am puzzled this makes no difference, but maybe it confirms the issue is elsewhere.

Brad, to answer your question, and as posted above, I'm on Win 10 Anniversary, 6700K at 4.8 GHz, GTX 1080, currently on driver 382.05 but have tried newer and down to 376.33. I'm afraid it's too late for me to test without add-ons, I have the full Orbx suite installed, as well as AS16/ACSA, PMDG 747 and TFDi 717.

Latest round of tests done with MAX_POINT_LIGHTS and MAX_SPOT_LIGHTS at 100, by the way, no idea if this helped/impacted.

Cheers,

Vince
Vincent Mounier
Kevin Cartrette
Lockheed Martin
Posts: 1111
Joined: Tue Aug 14, 2012 6:47 pm

Re: Massive FPS drop with landing lighs

Post by Kevin Cartrette »

Hey Vince,

Switching between AA types does not require a restart. Unfortunately, it sounds like with your combination of settings it isn't possible to maintain decent FPS due to the amount of per pixel work. Dynamic lighting per pixel is very expensive, the light count and size of light influence being the biggest factors in the cost. To reduce the amount of per pixel work try reducing the following since the biggest hitters are dynamic reflections, dynamic shadows, water reflections, dynamic lighting, volumetric fog and cloud/autogen draw distances. You can try reducing these in situations you don't need them or aren't near water.

Changing the max light counts will only have an impact if a scene is exceeding those counts. We do screen space tile lighting, so if you are zooming into areas with large amounts of lights covering the whole screen, VC's and zoomed into high density light areas, that will also be the hardest hitting cost per pixel on the GPU.

We will continue looking into ways to improving performance as V4 matures.

Thanks,
-Kevin.
Prepar3D Graphics Software Engineer
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