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Kuragiman

Chasing My Tail?

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So I am playing around in Prepar3D 2.4 (still haven't jumped to 2.5).   I bought a new GTX 980 and installed it.  I wiped the shader directory out and blew away the Prepar3D.cfg file and let it build a new one.  My settings are pretty high I will admit but I did this on purpose because I wanted to watch the performance on my monitoring software.

 

My test bed was FSDT's KLAS sitting at gate C18 with 40% AI traffic.  2048 x 2048 textures.   4x MSAA. 8x Ani.     All sliders maxed on the graphics except for the mesh resolution.  It's one to the left.      Autogen trees/buildings are normal and scenery complexity is Extreme.   Lighting is full on with cloud shadows and object casting.  Terrain casting is still way to much punishment so I don't use it.

 

I had ASUS Tweak open and monitoring the GPU and I had Progress Lasso open monitoring my 12 cores.   Here is where the tail chasing starts.    Maybe a tech guru can explain it all to me.     My new GPU will NOT go beyond 40% usage.    It doesn't matter if I max out everything or turn everything off.   P3D refuses to use more than about 40% of the power the card is capable.   Every single other game I run always pegs the card at 100% with incredible results.   I am stupid impressed by this card's performance in other games such as ARMA 3 and Skyrim.    Those aren't simulations though, at least not as detail.  I know this.

 

The CPU is banging away on the 4 cores I assigned to P3D.      I have 0-11 cores.   I use core 5, 7, 9 and 11 for P3D.   All other cores run other processes and add-ons for P3D.    Core 5 is around 80% most of the time with 7, 9 and 11 bounce around between 20-40%.      Total processor usage is 25-35%.

 

Does P3D *EVER* use 100% of the GPU with anyone's setup?     Even in a thunderstorm with cloud detail to MAX, I still don't get past 50% usage on the card.   Something is obviously bottlenecking things right?   I can't figure out what that could be.   The CPU?  The GPU?  The RAM?  The Front Side bus of the motherboard?   Evil gnomes?

 

I have an i7 3930k @ 4.4ghz with GTX 980 OC 4gig card.   32 gigs of G.Skill 1866mhz RAM is up on a X79 Sabertooth motherboard.   My sim runs on a Raptor 10k RPM drive and is the only thing on it.

 

My frame rate doesn't even really move that much between low and high settings.     The Default F22 runs like crazy at around 60-80 FPS in the VC.    The entire sim is smooth which is what you want, more so than FPS but it still bothers me to get into a heavy hitting airliner like an Aerosoft A320 or the new PMDG 777 and watch the FPS plumet to 20 FPS at HD airports and watch the video card just sit there at 40% usage.   My brain tells me that if the game would just use the other 60% I could have the golden 30 FPS and be smooth with high details on.   Why can I never get there?   Is the ESP engine really that bad at using hardware, even with LM's heavily modified coding or do I just have a badly configured system?    I wake up at night crying because my rig chews up every game on the market accept P3D.

 

I haven't even bothered learning to fly the 777 as it sits around 18 FPS, even at default airports.   My brain can't handle it.   It's smooth but lagging with head movements.   It is very immersion breaking.   Other planes perform better but that's because they don't have 20 gauges running with detailed simulations of systems I am sure.

 

Here is fun fact.    Sitting at the gate looking at the buildings.  The FPS in the A320 is about 23 with traffic on.   When I look behind me toward the desert the FPS shoots up past 40 which of course yields smoother head panning.   Heaven is behind me, hell before me.   

 

I should just fly but I keep hearing this nagging voice telling me "Dude, you have a powerful system… you have to be missing something."    Okay.. I am rambling now.   So apart from the usual "Shut up and fly" responses, is there anything you tech guys can think of that I might have screwed up or is this just how it has to be until we can have 8ghz processors?

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After my upgrade from a gtx 570 to a 970 I've cine to the conclusion that P3D is still just FSX with a few enhancements...

 

It's still cpu bound and won't take much advantage of a power GPU (except in extreme resolutions and or multi monitor). You'll still see black texturs at addon airports as you pan away and back again. Kinda depressing but it is slightly more optimized for GPU usage than FSX , as far as I can tell.

 

If you unlock your fps , naturally your GPU will show a higher usage - try that too

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After my upgrade from a gtx 570 to a 970 I've cine to the conclusion that P3D is still just FSX with a few enhancements...

 

It's still cpu bound and won't take much advantage of a power GPU (except in extreme resolutions and or multi monitor). You'll still see black texturs at addon airports as you pan away and back again. Kinda depressing but it is slightly more optimized for GPU usage than FSX , as far as I can tell.

 

If you unlock your fps , naturally your GPU will show a higher usage - try that too

 

I always fly with unlocked FPS.  If I limit the FPS to like 30 or even 25 the simulation NEVER hits those numbers.  It's always about 4-5 FPS under the limit I set which I find strange.     If it can hit 40 FPS unlimited you'd think it would peg at 25 if I set 25 as the limit but NOPE.

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Yeah there is an explanation for that...  I just can't remember where I read about it.

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You'll still see black texturs at addon airports as you pan away and back again.

 

One fix for black textures (particularly on payware airports) is to all add in a higher TextureMaxLoad (e.g. =30) into the P3D.cfg. Your 980 should easily be able to handle it. 

 

Brian, to further improve performance, have you tried a FFTF of 0.01? How about the freeware Air Traffic Manager? Your GPU is probably twiddling its thumbs because your CPU can't keep up, particularly at LAX @ 40% traffic...

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On my system with two 970's in SLI (yes it does work some) I can get 100% on both cards in heavy clouds, rain at high density airport in a frame hungry a/c. So saying that P3D never maxes the GPU or CPU is not correct.

 

What happens if you just use the CPU w/o assigning ANY cores - just let it run? Use heavy clouds and terrain shadows and see if that kicks it up. Increasing traffic hits the CPU harder than the CPU.

 

On my system, when it DOES get to 100% GPU - then my FPS start to degrade. If I can keep the GPU's mid 50% I can go all day long at a smooth 30fps - I don't run unlimited - waste of power.

 

Vic

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One fix for black textures (particularly on payware airports) is to all add in a higher TextureMaxLoad (e.g. =30) into the P3D.cfg. Your 980 should easily be able to handle it. 

 

Brian, to further improve performance, have you tried a FFTF of 0.01? How about the freeware Air Traffic Manager? Your GPU is probably twiddling its thumbs because your CPU can't keep up, particularly at LAX @ 40% traffic...

 

TML or Texture Bandwidth Multiplier?

 

I see a TBM and a TML=2048

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Ryan that's in my guide in my sig. or if you mean TextureMaxLoad its

 
[DISPLAY]
TextureMaxLoad=30

 

@Brain I would try setting it to run all core. You seem to have a problem it might be the way your using your cores.

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Ryan that's in my guide in my sig. or if you mean TextureMaxLoad its

 
[DISPLAY]
TextureMaxLoad=30

 

@Brain I would try setting it to run all core. You seem to have a problem it might be the way your using your cores.

 

The problem I had when I ran all cores was I would get core thrashing, in which the performance meter would bounce up and down creating a jagged looking mountain mess which is not good for smoothness and stability.   Core thrashing represents stuttering.   SteveW helped me figure that part out.   I found that running cores 5,7,8 and 11 makes the performance graph flat line which is desireable from my understanding.  It means it is keeping a smooth and steady data rate between CPU/GPU/FSB.

Yeah there is an explanation for that...  I just can't remember where I read about it.

 

I believe this is why they tell you not to limit using P3D's settings but using an external frame limiter which actually can hit your target number you set.

One fix for black textures (particularly on payware airports) is to all add in a higher TextureMaxLoad (e.g. =30) into the P3D.cfg. Your 980 should easily be able to handle it. 

 

Brian, to further improve performance, have you tried a FFTF of 0.01? How about the freeware Air Traffic Manager? Your GPU is probably twiddling its thumbs because your CPU can't keep up, particularly at LAX @ 40% traffic...

 

I run with TML @ 30 and it really does help on a high end card to stop black textures.   My black textures would be more on the AI aircraft around me for a second.   TML of 30 pretty much eliminated that.

 

I already run with 0.01 and that did give me a few more frames on my system while keeping the ground textures relatively intact.  If I am in a fast mover like a jet fighter FFT 0.01 is not a good idea.   It can't keep up and everything start to blur apart.    Commercial jet liners are okay on FFT 0.01 though.

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What you see is not really a surprise. As Ryan has said, P3D is still CPU bound in most situations. This is especially evident when running complex and CPU heavy add-ons like the 777. This is very much supported by the fact that when following discussions here on AVSIM then you can see that when people run a GPU which surpasses a certain performance threshold like the GTX760 then they get mostly the same fps. With minimal variance across the different GPUs. This only changes when you add specific GPU intense tasks like running high levels of anti-aliasing. So If you want to improve performance the only thing you can do is either reduce CPU intense tasks (e.g. run less complex add-ons or turn down AI) or improve your single core CPU performance by moving to a Haswell or Haswell-E. Having more cores will also not help a lot as P3D is limited by the core which coordinates all the parallel threads. Nevertheless with your setup it should be possible to achieve around 25 fps in the PMDG 777 at a large airport.

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Well I just did a fresh install of v2.5 and picked up the PMDG 737NGX.    I managed to get it to 30 FPS in the VC while sitting at DFW which is a very large airport in a highly populated area but I still just shake my head at watching the GPU running at a whopping 12% usage, bouncing up to 30% occasionally.    I had to compromise a lot to get the 30.   Slid the sliders to Sparse and took Tessellation all the way down to low.  I thought the whole point of Tessellation was to move all the intense processing onto the GPU?   Isn't Tessellation suppose to help on high end GPU systems?

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I hope this helps some - http://www.nvidia.com/object/tessellation.html. Not the way I understand it.

 

Best regards,

 

I did a lot of reading over the last few hours about Tessellation and it's actually not very helpful in the case of Prepar3D and the type of flying I do.   It generates unnecessary work loads on the GPU with very little to gain in visual quality for someone who flies high flying jets.   Tessellation is more of feature better suited for GA fliers who have less demanding aircraft at their disposal who fly slow and low and can afford the extra vertex points that tessellation creates.   I am going to take this to heart and create two profiles.  One will be for my 777/737/A318-A321 simulations and I will make a GA one for my 208B Grand Caravan and Twin Otter simulation.    

 

I also learned a valuable lesson in how to properly lock your frame rate down and use V-Sync and Triple Buffering to create a smoother simulation.  Seems to be working.   AI aircraft however break the bank and push the FPS back downward into undesirable territory.   There was another thread talking about how much AI craft people use and given what I know now I still don't know how some people can claim 100% AI traffic and not have a complete slide show in front of them.   They must have the most basic of models specifically designed to have very little impact on FPS.   Packages such as WOAI and the controversial ### AI have very detailed models that I think eat up frames pretty quick even on the best systems.

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I did a lot of reading over the last few hours about Tessellation and it's actually not very helpful in the case of Prepar3D and the type of flying I do. It generates unnecessary work loads on the GPU with very little to gain in visual quality for someone who flies high flying jets. Tessellation is more of feature better suited for GA fliers who have less demanding aircraft at their disposal who fly slow and low and can afford the extra vertex points that tessellation creates. I am going to take this to heart and create two profiles. One will be for my 777/737/A318-A321 simulations and I will make a GA one for my 208B Grand Caravan and Twin Otter simulation.

 

I also learned a valuable lesson in how to properly lock your frame rate down and use V-Sync and Triple Buffering to create a smoother simulation. Seems to be working. AI aircraft however break the bank and push the FPS back downward into undesirable territory. There was another thread talking about how much AI craft people use and given what I know now I still don't know how some people can claim 100% AI traffic and not have a complete slide show in front of them. They must have the most basic of models specifically designed to have very little impact on FPS. Packages such as WOAI and the controversial ### AI have very detailed models that I think eat up frames pretty quick even on the best systems.

Would you mind sharing what you did to lock your frame rate down and use v-sync. For my system (i5 3570K @ 4.7 & GTX780) the only way to yield good results is to set vsync to adaptive in Nvidia control panel, vsync on in P3D and fps to unlimited. If I lock fps it's just a stuttering mess.

 

Richard

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the only way to yield good results is to set vsync to adaptive in Nvidia control panel, vsync on in P3D and fps to unlimited. If I lock fps it's just a stuttering mess.

 

Exactly the same setup I use on my system. Locking the frames in P3D or via an external program/driver most of the times leads to stutters. The only case in which locking the frames yields a slight improvement is when an add-on has fps which wildly fluctuate between 30 and 60 fps. The Aerosoft Airbus is an example. In these cases, locking the frames to 40 or 45 helps on my system.

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