Poor Performance with RTX 3080 and 3900X CPU " Limited by MainThread"

Just out of curiosity my question to you all, i asume if youre internet connection is set to unlimmited, might it be possible that your internet provider has in their statement Policy “fair use” mening that if you use large quantaties of down/uploads, that they can turn youre speed down for the rest of the month.

…and people tend to forget…the Internet has no SLA :slight_smile:

Solution: Disable Vsync.
Got the same problem.

GPU is not fully loaded while Vsync enabled.

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Thanks for the reply. So you are saying that although it looks like I have CPU capacity “free”, in reality I don’t as the monitoring toll doesn’t show spikes in load?

Yep.
There’s a lot of discussion on the forums here on CPU & GPU performance and limitations…along with a lot of anecdotal views.
In the end MSFS is a demanding application and a lot of people want to set everything to Ultra but the reality is the hardware can’t support that.
The key thing is adjusting settings so you get sufficient FPS that you enjoy a smooth flight experience. (and that doesn’t mean you need to hit 50-60 FPS).
There are a lot of factors that may interfere with a smooth flight and cause stutters/low FPS. For example, what other background processes are running at the same time as MSFS (e.g. Antivirus software, other installed apps such as RGB control etc just to mention a few).
In the end, we’ll only get as good as our budgets allow.
There are so many variables and different combinations of system hardware I appreciate it’s challenging for Asobo to create a one size fits all solution.
The basic software design relies on one thread for scheduling and the better a CPU can handle that the better.
Could Asobo try to redesign that…maybe but I suspect that would be a very painful software redevelopment and one that would cause all of us a lot more grief.

Great thanks. I’m pretty happy with what I’m getting right now - 40-50 FPS typically, but less over big cities, on ultra everything with no stutters - so nothing to complain about at all. I was trying to understand why I didn’t seem able to take more advantage of the seeming spare capacity in nmy CPU.

What are your specs again? Also, are you at 200 a piece for Anti-Aliasing and other settings? I’m a newbie “gamer” who spent $$ on what looked like a good deal on a Dell Alienware Aurora R11,RTX 280 Super build, and I’m not getting smooth performance on all ultra and max settings especially over cities. I also am mad at myself as I purchased on 1st of September and only a few months later Dell Alienware Aurora R11 has the RTX 300 series at roughly the same cost. Any advice suggestions on what I might or might not be doing wrong?

Hi specs are per above post

Not in the sim right now - but I will post my full settings etc later

Update, I got some pretty good 5 FPS on the minimums with a 100MHZ overclock on the CPU 4.9GHZ to 5GHZ, reinforcing that the mainthread limitation is the real bottleneck in this game.

OBS: My VGA is a RTX 3090

I can’t tell if this post is serious or not. There are enough reports out there of people with top of the line hardware and brand new PCs to verify that this issue exists despite having “clean” PCs. Look around the forum. The countless threads on here complaining about performance on high end hardware are not all down to people not following your advice of “cleaning” their PC. And for the record, my PC is “clean”. It is running on a fresh install on Windows 10 and has nothing on it except for FS2020, X-Plane, and a few games. Again, take a look around the forums

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This @BUGSWATER better be joking. I have formatted my NVMe and installed a brand new Windows 10 just to play this Sim, there is absolutely no other software that should be interfering.
So yes definitely not a software or “cleanliness” problem.

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I have 9400f, 32gb ram, rtx3070.
I am getting less fps than my old gpu.
Gpu and cpu utilization is about 50%
Why don’t they get utilized properly?
Second question, is geforce experience “optimized” or "not optimized " really mean something?

The ‘Limited by Main Thread’ notice is a limitation of the current game architecture, and not necessarily a user’s other software.

While a CPU with more powerful threads will reduce the chance and severity of a bottleneck, the way the game assigns tasks to other threads needs to be further optimised, something the developers have mentioned.

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Rubberbanding and stutters used to be a feature of DirectX back in the day when OpenGL was still a real thing. It was a pain in the rear and it never seemed to get fixed.

I will say that my 10 year old Dell T3500 with a 6-core X58, 48GB RAM, slow SSD, and GTX 1080 runs pretty well at 1080p. Even in the cities, I get minimal stutters. That’s with almost everything on ultra, render scale 100, LOD’s both 130, and instrument refresh is high. As long as your GPU is keeping up it will always be limited by the main thread no matter how fast the CPU gets it done.

After some screwing around on my own I think the problems are related more to the GPS and gauge systems than anything else. I get chunky photogrammetry for no good reason sometimes, but it’s pretty rare outside of Manhattan.

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Did MS/Asobo publish their design documents outside of the NDA? Are they available to 3rd party developers?

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Not that I know. I guess third parties are not bound by any NDA, the only legal req is no sw rev.eng… But from the results it is quite easy to figure out some basic design elements. For example from some bugs you can see that parts of the old FSX were reused.

extremely low fps and very low utilization of cpu and gpu. see the pic…

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Topic moved out of archives and into #bugs-and-issues:performance.

Hello there.

RTX 3080/3900X@4.3/32GB 3600 CL16/4K Ultra.

Since USA update, more stutter for sure…

But I wanted to know also if the photogrametric trees are killing you like on my config…

Central Park in NYC : 15 FPS or less at 200-300 feets.

What are your FPS there in 4K Ultra ?

All around New york, every time there are a lot of trees in low altitude my FPS drop like crazy, but at the same time power consumption of the GPU drops… Usually 90-105%, drops to 50-80% when it happens.

Dev mode does not show a saturation of the Vram, but wondering if not the case in fact.

All around NYC I’m in low to high 30’s otherwise, around 500-600 feets. Only those trees are killing my config

We need feedback from 3090 users with their 24GB of Vram…

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I have an i9 CPU and RTX3090. I started having terrible stutters with any 460.xx driver. The cause was Gsync and my Acer 4k Freesync (supposedly compatible) monitors. They worked great in 45x.xx drivers but not with the latest.

Turning off GSync cured the stutter.
Do you Have a GSync monitor and is GSync turned on?
May be unrelated but just my personal experience.

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