Severe FPS degradation in DevMode

Hi all, Over the last 3 or 4 months I have been getting absolutely awful FPS
stutters while editing my Scenery in DevMode. I build the package in-sim and
Load into the Editor, but the FPS issues persist even when a copy of the built
package is present in my community folder. I have a really powerful system
with a Ryzen 9 5900X and RTX 3080 along with 32GB RAM so there is absolutely
no reason why my FPS should be this poor. I get 60+ FPS at 1440p Ultra when
not editing my scenery, but this current stuttering makes my project
absolutely unusable to edit. Unfortunately I can’t pinpoint the exact time
when this started happening, and I have done a full sim reinstall and SDK
reinstall since. I’m at my wit’s end quite frankly, as making my scenery just
isn’t fun anymore when dealing with these massive stutters.

I’ve been having the same issue. Even on smaller projects. It’s so painful
trying to edit sceneries when it’s dropping to single-digit FPS (spiking to
over 300ms mainthread) and often just registering every third mouseclick for
everything I’m trying to do. Exiting the project editor, going back to main
menu and restarting the flight does not clear it up. The issue persists until
I restart the simulator which clears it up for me. It then starts happening
again 1-10 minutes after I load a scenery project again.

Same thing here. Drastic decrease in perf over time when editing airport.

@WombiiActual exactly the same here. Editing my scenery currently with this
issue makes it practically unusable. Not sure why more people aren’t making
noise about this as how are other devs coping!?

I was starting to think it was only me but actually you confirm this is a
somewhat wide spread issue. BTW, at least one other topic is open on that
issue <https://devsupport.flightsimulator.com/questions/6555/performance-
drops-as-we-work-in-dev-mode-su8.html>

Yes, the more ‘stuff’ you have in your scenery, especially in scenery editor
mode … give it about 20 mins and you have to restart the Sim the FPS is so
bad. There were some improvements when the exporter assigned random collision
faces to objects bug was fixed in SU8 and that did help a little bit, but the
overall FPS drop issue is still there. It doesn’t require long flight to find
it, only work in a complex airport in the sim for 20-30mins and you’ll have
the issue show itself. We can confirm its been an issue since SU6 as well and
its 100% repeatable (I restart about 5-6 times a night) PS Original Poster, in
your video is what I see after about 15mins, I find pointing the camera
straight down and flicking between scenery and material modes helps but it’s
only temporary as it loads and unloads the scenery editor overlays.

I can’t even place objects since is not loading the Assets, it is that bad.
Please try to address it as soon as possible … Thanks

Same here. It starts smooth and then performance decreases over time…
Sometimes it results in a CTD after a point when Dev Mode would become very
slow and unusable.

I think that’s a different issue of the model loading but not displaying. You
can usually get it to display by clicking on the material editor and then
jumping back to the scenery editor to force a scene to reload. No ideal but it
works at least.

I’ll try! Thanks!

I just want to add it seems this has been fixed in SU9 beta. The overall
performance is a lot lot better.

Hello, Yes, fixes were made on this specific topic for the SU9 Beta. Would it
be possible for the other people who reported the issue to confirm that it’s
fixed on your end as well? Thanks!

After updating to SU9, the FPS degradation issue seems gone. I can even
potentially see better performances. Thanks!

I am still having this issue even after SU9 with SDK 0.18 while editing the
airport. If placing objects around the performance is good.

I am seeing massive FPS drops with latest sdk build 0.18.0.0 and latest sim
update. When editing my airport in dev mode after 20 to 30 mins dropped to 4-5
fps all I had done is add some painted lines in a few spots. has been doing it
before without adding painted lines so don’t think that is relevant fps just
seems to drop. starts off at my locked 30fps which isn’t even stressing the pc
to the 4-5fps.