The problem of perspective lag appeared after updating su15. The graphics card utilization rate was very low in the first few days. It got much better after playing for a few days, but it still could not maintain 100%. The average utilization rate in the air was about 60%, and it was even lower on the ground. Before the update, it could maintain 100% utilization.
I used to have lag when rotating my view, at least the first few times I did it. Then it would smooth out. I’m guessing it was a cache (maybe Rolling Cache, which I have enabled) that was smoothing it out.
Since SU15 I have zero lag when panning around in either cockpit or external view. The sim never been smoother on my mid-range PC. Zero frame stutter, and zero lag when looking around, even when my FPS drops to levels in difficult areas that would previously result in stutters. I would call it a profound improvement.
See existing bug report:
Funny, I still get the exact same stutters when panning around as you describe the first three, maybe four full 360° rounds. It was always like this and still is after SU15. Settings unaltered.
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the offscreen precache feature helps with this,
set it on ultra and see what it does
it will use more cpu when NOT turning the view though… so its a balancing act
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Already have it on ultra, does nothing, no matter what I put there (of course, things popp up when using lower settings).
What are your computer specs (basically…)
13600K without OC, 2x16GB DDR4 RAM and a RTX 4080, using DX12 and Frame Gen, MSFS installed on a SATA SSD with 2TB capacity.
Plenty of horsepower.
I can tell you that I have uninstalled EVERY nVidia driver I’ve tried lately, and always reverted to a clean install of 536.67. Of course always using DDU to uninstall, and always clearing all the caches when I do.
When this happens it’s invariably due to Main Thread limitation, which is related to CPU performance and how I/O-bound the sim is, not the GPU. The reason it likely happens on panning is because the sim loads new textures that were not previously in view to send to the GPU, making the main thread temporarily I/O-bound as it reads from disk, then draws the new objects that are now in your view before sending that data to the GPU to render, which delays the frame and creates the stutter.
This is why terrain caching helps (when the data has been loaded once) because it removes the I/O aspect from future fetches, and fetching from memory is orders of magnitude faster.
The solution is to make your main thread less busy and generally the only way to do that in the sim is to reduce TLOD and other CPU-intensive settings like traffic and multiplayer, or get a faster CPU. Though as those with the fastest CPUs will attest, no CPU is fast enough to avoid some stuttering at some point. Overclocking might help, but you have to get to a threshold where the main thread can run uninterrupted with as few blockers as possible to enable it to keep up with the frame rate.
(A note that frame gen won’t help here either. Long frames will just get doubled and the stutter will still occur.)
I have a 13900K mildly overclocked, 64GB DDR5 and a 4090, and I still get these stutters-on-pan on the ground in complex scenery and particularly with heavy traffic or heavy multiplayer. Usually when I get into the sim I will pan around in all directions and get as much as I can into the terrain cache and this lessens the problem, but it won’t go away entirely.
That’s what I’ve found, anyway. YMMV as always.
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This is correct but don´t forget a very important factor: the initial cam panning freezing and general freezes during gameplay were introduced by one of the updates before SU15. This was not happening before and was caused by slow memory management (wrong design), not by any HW limitation. SU15 in theory fixed the slow memory management (at least partially because freezes still exist) but on the other hand it also brought an intentional memory release to help consoles with their max memory limit. To save memory the main thread has now to deal with extra I/O that was not exisiting before (and reload assets as you explained), plus with all the previous factors that were already existing before (traffic for instance).
So what we see now is still not a HW limitation but a design decision that increased workload on its own. Even if the intention was good or needed for some systems the result may not be the optimal one as the problem is also reproduced now both on consoles, mid range systems and in more powerful ones too. So it was basically propagated rather than fixed. Is SU15 then working better? Yes, better than SU14 maybe but not better than before I would say.
Cheers
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I think this is spot on.
I’ve come to believe that one of the most important things we can do as users is balance CPU/GPU latency. Since SU15 I’ve used this video to help me balance my latencies (‘Limited By’ flashes rapidly between ‘Main Thread’ and ‘GPU’) and things are very smooth.
I definitely see a huge improvement fro SU14 in that regard.
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