RT 2080 running at 100%

[Yeti42]

I apologise for this initial post upfront, I don't have access to my gaming rig today so can't post accurate settings info, however:

 

I have an RTX 2080, I5 4670k running at 4.6 Ghz and 32 Gb Ram running at 1800 with a 4k LG 42" tv as a display, HDR is enabled on the TV. vsync is turned on so frames are limited to the refresh rate of the TV which is 60Hz. Graphics settings are custom High (apologies will post actual settings later)

 

Now the issue ;) My CPU is running at about 60% during single player F14 missions, GPU is running maxed out 100% pretty much all of the time. This doesn't seem right, tweaking Nvidia settings has some impact but frames rates frequently drop below 35 fps with the CPU never maxing out. Obviously dropping the in-game graphics settings to medium has an effect but the whole reason a purchased an RTX 2080 was to run at high settings in 4k. AM EXPECTING TOO MUCH? Is the inherent problem 4K on high settings or is there something else?

 

Will post full info tonight when I get home, couldn't wait to see if anybody had any ideas... ;)

 

Thanks in advance for any helpful hints...

[Vertigo72]

Your cpu "running at 60%" doesnt really mean anything. You have a 4 core/4 thread cpu. DCS can at most fully utilize 2 cores. And only one of those will be performance critical and probably close to 100% all the time. Windows will shuffle those threads across the cores for various reasons, including spreading the heat, so looking at task manager you will see 4 cores that seem underutilized, but that doesnt mean you are not cpu bottlenecked.

 

The 100% utilization rate on the GPU and low FPS does strike me as odd, depending what those "custom high" settings are. If you are going to combine high MSAA with 4K resolution, well, I dont know if even a 2080 can pull that off with the F14. My 1070 certainly struggles even at 1080p, and enabling mirrors on a carrier creates a nice slide show.

 

Here is my suggestion: use settings that others can easily replicate (say DCS default high), chose a mission or training that others can also load, and then we can see if your performance is out of line or not. Since few of us use a 4K display, perhaps note your FPS on 1080p as well.

Edited May 2, 2019 by Vertigo72

[Yeti42]

Thanks, I will run some baselines with standard settings. Interestingly though, I was talking about all 4 cores, 3 cores were fairly evenly loaded and the 1st core was a lot lower, no core was above 75%. After disabling Vsync, GPU load dropped to around 90% and CPU load increased to an average of 80% with one core at 100%. Framerates obviously varied widely with no vsync (25 - 150)

[Vertigo72]

I was talking about all 4 cores, 3 cores were fairly evenly loaded and the 1st core was a lot lower, no core was above 75%.

 

That doesnt mean anything. Depending on the cpu, Windows may relocate the main DCS thread to different cores tens or hundreds of times per second; if this sounds stupid, keep in mind the overhead penalty is peanuts on a cpu that does 4 billion operations per second and the upside is an even load and heat distribution which enables higher boost speeds. So its usually a net win.

 

You only get to see average loads on much longer time scales, like seconds, which for a cpu seems like a lifetime, but at any given time, one core could, and most likely is, fully utilized. If it werent, windows would lower its clockspeed.

 

Note that this works different on different cpus. For instance, AFAIK on an AMD ryzen with precision boost, you will usually not see this behavior because it has preferred cores that can boost to higher frequencies. Windows will prioritize those.

 

last point; even if 50% of the time, all your cores would be idle, this doesnt mean you are not cpu bottlenecked. To simplify lets say a frame first has to be prepared by the CPU and is then handed off to the GPU. While the GPu does its work, the CPU would be idle. In this example both would take the exact same time. Increasing your CPU speed will still increase your framerate, even though your average core utilization is only 50%. Reality is far more complicated obviously, but you cant just look at one number and say, my CPU is fast enough, its not the problem.

Edited May 2, 2019 by Vertigo72

[Yeti42]

All four cores are locked at 4.6 so I can't see how windows could lower the clock speed. (turbo etc disabled) It also tells me something in that I see a significantly higher average CPU load when vsync is disabled...

[Vertigo72]

What do you think it tells you? Of course the load will be higher when more frames are being rendered. vsync basically allows both the gpu and cpu to take a power nap when they produced a frame within 16ms.

 

As for disabling turbo and clock scaling, fine, doesnt change anything about my argument. If I cant convince you with words, try clocking your cpu down by 1 GHz. Ill eat your cookie if that doesnt impact framerates.

 

BTW, 80% on a 4C/4T cpu? Wow..

considering how poorly DCS uses multiple threads, you seem to be more cpu bottlenecked than I thought.

Edited May 2, 2019 by Vertigo72

[GriffonBR]

Yeti42, recently I discoverd that somehow the Vsync on the DCS World video setup has some kind of issue. With my current setup (see my signature) my FPS drops to 50/45/35 in all maps, but when I disable de Vsync on DCS video setup and enable the Vsync from my Nvidia Drivers Setup I get constantly 60/55 FPS now (except the Normady map). Try this and see if helps you.

[Yeti42]

 

BTW, 80% on a 4C/4T cpu? Wow..

considering how poorly DCS uses multiple threads, you seem to be more cpu bottlenecked than I thought.

 

Oh dear.... be polite... who mentioned 80%... You're not being helpful and you're not talking to some spotty teenager who tweaks his CPU for fun. I work with software and hardware for a living and have done so for quite some time. If you don't have a constructive suggestion, please don't troll.

[Yeti42]

Yeti42, recently I discoverd that somehow the Vsync on the DCS World video setup has some kind of issue. With my current setup (see my signature) my FPS drops to 50/45/35 in all maps, but when I disable de Vsync on DCS video setup and enable the Vsync from my Nvidia Drivers Setup I get constantly 60/55 FPS now (except the Normady map). Try this and see if helps you.

 

That sounds like it may be the culprit, thanks, I'll try it ;)

[Vertigo72]

Oh dear.... be polite... who mentioned 80%...

 

Whoever wrote this:

and CPU load increased to an average of 80% with one core at 100%.

[Yeti42]

Whoever wrote this:

and CPU load increased to an average of 80% with one core at 100%.

 

My mistake, yes I did indeed say an average of 80%, obviously, the load depends on how much AI and other stuff you have going on in the mission.... the facts remains the GPU is at 100% which means it's a bottleneck especially if you account for vsync limiting. I really don't want to continue this conversation with you any more... you're not adding anything.

[Kazius]

I don't care if a person has an RTX 2080 Ti and use a 60Hz monitor and vsync. They will still 100% utilize that GPU. The game is currently ahead of hardware specifications. Top that off, for each map they add they often add more structures and possibly more detail to those structures. On top of that new aircraft coming out get increased polygon counts.

 

DCS developers will likely be pushing the boundary of video cards on a constant basis.

 

Your running 4k so your card has to calculate 2x as many pixels as normal 1080p. And if your not using vsync on a low hertz TV then your card is just going to produce as many frames each second as it possibly can whether or not some get skipped.

Edited May 2, 2019 by Kazius

[etherbattx]

the facts remains the GPU is at 100% which means it's a bottleneck especially if you account for vsync limiting. I really don't want to continue this conversation with you any more... you're not adding anything.

 

for someone who is an experienced expert in software and hardware, you misunderstand some of the basics.

 

he was trying to explain how it works. modern multicore cpu’s and gpu offloading doesn’t work like 486’s did decades ago.

[Dudikoff]

Obviously dropping the in-game graphics settings to medium has an effect but the whole reason a purchased an RTX 2080 was to run at high settings in 4k. AM EXPECTING TOO MUCH? Is the inherent problem 4K on high settings or is there something else?

 

4K is too demanding to simply max everything out, you need to tweak some more demanding features probably.

 

What's your anti-aliasing setting at? 100% GPU usage indicates that your current settings are too high to maintain 60 FPS, I'd assume it's the AA.

[BitMaster]

Aint it obvious what it tells you ?

 

100% GPU means your CPU is "still" good enough to feed it at given LOD to maximum extend = perfect and desired ..IF...you dont use ANY vsync, as 100% GPU is what you paid for.

 

BUT..really but..if you have VSYNC set to 60Hz and your GPU still goes full tilt 98-100%...THEN..your GPU is too small or better said, your res or LOD too high.

 

Your GPU Load should actually stay a good portion below 100% so you can maintain 60fps at all costs, anywhere, any angles, any terrain, any module. If you often hit 100% means that you then also likely cannot maintain 60fps and drop.

 

 

I dont play 4k, but my 1080ti does a good job at 2560x1440 and 60fps locked at a fairly high LOD. When it's locked, I hardly ever get to 100% and drop below 60, usually I am at 65-80% GPU load and rock solid 60. The most I let it drop is roughly 55-58 for seconds, I can accept that. If it dropped lower I'd crank back my LOD to get back to 60fps for 98-99% of my airtime.

 

LOD can make 130fps a slide show, just click the wrong boxes ;)

[Vertigo72]

As I suspected, according to my tests, and results posted by others, rendering the F14 cockpit with DCS default HIGH settings, especially close to the ground where FPS are lowest, is almost entirely CPU (*) bound on even the fastest CPU's:

https://forums.eagle.ru/showthread.php?t=240207

 

If you have a fast enough GPU, you can switch from 1080p to 4K and it makes pretty much no difference in frame rate. So a highend card like a 2080 might enable you to run 4K at the same (low) FPS as at 1080p, but your lowest FPS is still bottlenecked by the CPU. At 1080p changing the clockspeeds of my modest 1070 made absolutely zero difference. I could upgrade to a 2080Ti and it would make no difference. I probably could downgrade to a 1060 and it might not make a difference at 1080p in challenging conditions (ie on a carrier or on the ground, and using default high settings). But changing the clockspeed of my Ryzen cpu, resulted in an almost 100% correlated FPS change.

 

(*) There is some good evidence that CPU IO might be a critically important factor, ie, L2/L3 cache, ram speed and/or latency. More testing is needed to determine that for sure, but I saw almost linear increases when overclocking my old DDR4 ram, and by far the fastest framerates where posted by someone with DDR4-3600. OP has a slightly dated CPU with small caches compared to modern CPUs, and DDR3 ram. Just sayin'

Edited May 5, 2019 by Vertigo72