Hi All,
First time poster so take it easy hahah,
I have checked heaps of forums on here and still struggling to find an answer!
I am running a
I9-11900kf
Nvdia 4090
32gb ram
DX12
but the sim just wont run smooth its always limited by main thread. I have Frame Gen on but the stutter just never seem to ease off and nil frame increase.
Should i be looking at a new CPU or does anyone have any other pointers?
Cheers
Lachy
This looks quite bad. Don’t know what your lod settings are, or what other things you are running at the same time, but on a 777 at FL280, you should get 40+ fps with reasonable settings. I don’t have the 777, but on a300, which I hear is not very optimized, I get around 40-50 fps at that altitude without FG, i have a better cpu though, 5800x3d, but still you should get atleast 30-35+.
I would check what other programmes are taking cpu and specially programs which interact with MSFS using simconnect.
Also, have tried restarting the sim? I have seen similar behavior on my setup where I would get less than half the expected framerate for no conceivable reason, but that’s very rare and usually fixed after a restart.
Only 1080p on a 4090 is the biggest issue here. If using TAA try pushing up renderscale to at least 150%, and lower LOD and traffic settings to bring down your cpu latency. I suggest you leave frame gen off until you have some kind of balanced output to work from
Sorry, this post meant for the OP
Try without addons.
Rename community folder to community_copy
Create new community folder.
Launch msfs and Cessna 152
Hi SuitingRocket,
DensestSnail is 100% correct above - your GPU is barely ticking over with a 1080p image, whereas the complex aircraft and all the other aspects of the simulation are absolutely hammering your CPU, which you can clearly see in the performance trace. This is what is causing the stutters and low frame rate.
I had exactly the same issues in my previous pc using an 11700K, and there are a few things you can try to improve the situation.
First, try turning off hyperthreading in your BIOS. It isn’t necessary for MSFS, and can allow your CPU to focus a little more on the essential threads only.
If you have any overclocks applied, try reverting to stock speeds and also check the temperatures the CPU is reaching - MSFS is very hard work for them and really good cooling is important.
Ensure that anything else in the background unrelated to MSFS is shut down wherever possible, as these processes also load the CPU.
Try reducing your settings for air, ground and sea traffic and see if this helps, and turn off multiplayer if it’s not in use. Turning off Live Weather can also help, as long as you’re happy to use the weather presets instead. If not, you could compromise by using something like Rex Accuseason Advanced, which gives you a lot more options and can offer realistic seasonal weather.
Finally there will be settings adjustments that can help. Leave the Developer mode fps counter on, and spawn a complex aircraft over a big city or airport, then tweak the settings bit by bit. The ones that have the biggest impact on the CPU are Terrain Level of Details, Terrain Shadows, Objects LOD, Terrain Pre-Caching and Texture Synthesis. Start with the two LOD sliders at 100 and reduce all the others mentioned above by a couple of notches and see how it looks. Pause the flight, tweak further and restart. It can be a bit of a painful process, but you will get the PC offering the best performance it can by the end of it. The performance trace at the top will show you spikes and flash yellow or red when the CPU isn’t keeping up, so it’s just a matter of experimenting with the settings above until you get the best balance you can.
Ultimately your GPU can handle a 4k screen, so that might be worth considering, but the CPU is the most critical component for MSFS and that has been superseded by more recent generations of intel chips as well as the AMD X3D cpu’s. If you do decide to change it, you’ll have to change the motherboard as well, so if you want to stick with intel I’d wait until the 15th Gen and their new socket are out. The same goes for AMD I believe as they also have new chips due shortly.
In the meantime, your current CPU can definitely do a lot better than a stuttering 22fps with a bit of experimentation, so good luck.
Hi @SuitingRocket69,
I’ve moved your topic from the Bug Reporting Hub category to the User Support Hub > Install, Performance & Graphics category as your post removed the provided template when completing bug reports, and it seems you may be utilising some 3rd party addons which could potentially be causing your issues. Hopefully moving this topic to the User Support Hub provides you with better help from the community to solve your problem! 
Thanks
The MSFS Team
The GPU isn’t the issue, and turning up render scaling will do absolutely nothing unless you turn it up so high that the GPU frame times become worse than the CPU frame times (meaning even worse fps).
I do agree with checking the LOD and traffic settings, as those will be the biggest contributors to CPU usage. If using a third party traffic manager, make sure AI air traffic is turned off in the sim. I made that mistake once, which hit me with double traffic and killed my CPU frame times.
I believe that balancing CPU/GPU latency is critical to the smooth performance of the sim. You might lose a few FPS when they’re balanced, but stutters will be reduced.
Also, OP needs to monitor temps. Open Hardware Monitor is a good free tool, especially since you can run it as an overlay gadget with only the most important metrics of your choice visible.
He is not running any GPU issue. Render thread and GPU have latency below 10ms, so GPU can provide more than 60fps in this situation. This also means the CPU isn´t a problem as a CPU HW problem would also block performance of Render thread in game as well. The problem is exclusively a main thread issue in game, nothing else. As RAM seems to be below max usage we could discard a big data swap being in process.
So as suggested by others try reducing main thread intensinve settings in game, starting by AI traffic. Disable it completely and check, then enable 10% offline only (that should be still ok for any system) and if that´s fine then try with online traffic. Any offline setting above 10% will start to have an impact on performance (around 200 AI planes can be spawned depending on area). That can be also the case with online traffic near urban areas or big hubs. I doubt problem is related to graphical settings, specially when not being at 4K, but try to set TLOD 200 as a maximum just for tests. Rest can be ultra with a 4090.
Cheers
This is new information for me. I’m aware that ‘Main Thread’ doesn’t equal ‘CPU.’ But I’ve always thought that it is most affected by the CPU performance.
There’s data getting stuck somewhere.
Unfortunately it’s not a zero sum equation and his gpu will likely be swamping his system with data requests. For all we know render thread could be re-rendering frames from scratch rather than simply repeating them or vice versa. Latency settings in NVCP can help-
Not in DX12. Even if it´s still beta this dramatically improves graphical performance and in particular reduces CPU calls, in favour of increasing GPU usage. Data requests from disk are also very few and light in normal situation. The highest data read from disk happens only during flight loading (blue bar) and you are always storing around 20-30km ahead in memory after that, so updates are periodic.
MSFS can be plagued with other performance daemons but it´s still a game where a fast GPU produces good results. However the main problem is still its poor main thread, as it does everything else and tasks are basically queued for each frame or few frames (even if a kind of parallel tasking is implemented). DX12 does not improve that as indeed the game CPU usage is normally very low. The problem of this game is that such long queues add a lot of latency per frame until everything is processed. Even if CPU is fast it will still need to read a super long list of tasks and as soon as anything is delayed a bit (for instance too many AI planes commands) it delays everything else. FSX era inherited code style, so nothing really new indeed. What you see now is exactly what was happening 10 years ago and the solutions are still the same ones.
First solution here is to reduce AI traffic as this is most likely what hammers main thread. Flying above 10.000ft the scenery details are not so demanding, so traffic is the only factor together with cloud textures that can kill performance, and clouds are not going to be a problem for a 4090 in 1080p. In the worse case you may also need to reduce TLOD but only if you are using anything above 200, as 200 is nowadays something average indeed after the systematic LODs reductions from the previous patches. But again above 10.000ft TLOD is just basically Bing textures only and low detail terrain mesh, so it only matters when you are close to ground level, where many highest details assets and terrain mesh can be displayed at once.
I have a 12900ks + 4090 and this is what I have seen in my system when I faced performance problems. I use the 4090 with 3840x1600 and 125% scaling, TLOD 200 and 10% offline traffic or online one (average 250 planes in most situations) and it still produces high fps.
Cheers
Pretty much 4k and a far cry from 1080p. This reinforces my point, 4080 and 90s were never intended for low resolutions and for MSFS devs it’s certain to be an outlier (3080 & 90s too)
Yes but remember that resolution is not the real problem in MSFS, even if it matters for texture loading. At ground level in a big city with high details and several custom buildings (so unique instances, not generic assets repeated many times) you will see a really high RAM and VRAM load (even beyond 20GB in some cases). You can test how, in such situation, reducing resolution to anything stupid and using low resolution textures does not increase fps. It can be a problem even without any AI traffic at all. However reducing TLOD below 150 there is the only thing that releases workload.
I remember I test I did months ago where every setting at low, low screen resolution as well but only TLOD 200 was still killing performance at ground level. GPU was still working hard while CPU was below 10%, which initially had no sense, but that´s because GPU was still doing a lot of scenery caching, even if details were so low. The only conclussion I could drop then is that scenery caching was storing all LODs (even if they were not required) just to faster access them when needed. That´s why reducing TLOD (so viewdistance) was the only way to reduce amount of cached objects and therefore cached LODs and used memory.
Memory management is one of the most important topics in MSFS, that’s why it always leads to problems, CTDs and performance issues. When Asobo wants to reduce memory they always reduce LODs and/or effective viewdistance, which matches what I saw during that test in the past.
Cheers
