CTD after 3.7.4 update related to AI (MSFS2020)

[Dave81]

just to add for me I use PSXT for traffic injection with AIG models and get the CTD with 3.74 MSFS2020

[hargetnj]

Hey!
So I use MSFS 2020, PSXT with AIG/FSTL Models, and receiving the CTD. I also had the CTD when on VATSIM, using the same models.

Today I unlinked GSX from the sim, and used PSXT with no issues.

I know there's a thread stating "CTDs are not caused by GSX" but unfortunately, it appears they may be. Plenty of users removing GSX from the equation and all is working as expected. :/

[virtuali]

I know there's a thread stating "CTDs are not caused by GSX" but unfortunately, it appears they may be. Plenty of users removing GSX from the equation and all is working as expected.

Of course CTD are NOT caused by GSX, that has been explained so many times. It seems that multiple users confirmed the crashes happens ONLY with an AI injector, not with GSX alone so, if anything, CTD might be "caused" by using both, if "caused" is the right term.

Because the real issue might just be the dreaded max simobject limit that, by using BOTH (add GSX objects + injected AIs), is exceeded, so what is *really* causing the CTD is exceeding that limit.

In any case, I just tried now with FSLTL, using two different injectors, first the one from FSLTL, and then with BATC. Made 5-6 Boarding at KLAX, no issues whatsoever. Installed FSLTL fresh, using all default options. In BATC, I have the AI density set to the suggested value of 5 so, again, all default.

[renkouchuan]

Yes I did all combinations with or without GSX. Those are the result with GSX on. Without GSX everything works fine and smothly. For your second question I assume nobody will use a professional injector to inject a default model so I can't give you the answer. Base on the information we've got now, I would believe it's models problem. I remember for your new update you brought out a funtion for taxi which can creat route to avoid AI, I don't know if these have any relationship.

[virtuali]

I would believe it's models problem. I remember for your new update you brought out a funtion for taxi which can creat route to avoid AI, I don't know if these have any relationship.

If they had it, I'm sure you would have noticed a crash only happened when calling the progressive taxi function, but nobody reported it this way. GSX won't read any AI unless:

- you open the 2d map AND enable the AI traffic layer

OR

- you start the progressive taxi function.

OR

- you select a gate, so it would offer the option to remove an AI on that gate.

Since I see several reports saying it happened while Boarding, it seems to indicate it's "just" a matter of too many *injected* objects, since both GSX and any AI generator injects Simobjects.

As I've said, I tested it with both FSLTL and BATC injectors, doing (many) Boarding in GSX, on a very large airport (KLAX), and I couldn't replicate any crashes. As I've said, I used all defaults for both FSLTL and BATC, and I turned off MSFS own AI traffic and also the parked airplanes, so the ONLY AI present were the injected ones.

What has changed in 3.7.4 is this:

GSX Pro Change: LOD Levels has been changed for ALL vehicles, to take advantage of the different LOD curve introduced with MSFS 2024 SU4, improving object detail in the short/mid distances.

This because we heard so many times users complaining our previous LOD levels were far too restrictive, so we took advantage of the new SU4 LOD curve, which shows better LOD for a longer time in a non-linear fashion, to improve visual pop-up quite a bit. Maybe this new less restrictive LOD is "just" too much for the sim to handle ? Nothing is free is this world: if you hate pop-up like everybody, you must accept the improved LOD would surely take more memory.

Maybe opening the default fps counter and checking your RAM/VRAM situation might be helpful.

[renkouchuan]

Interesting, sacrifice msfs2020 users's simobjects limitation to accomadate a new introduced msfs2024 function, and for those small RAM users even they don't deserve to fly anymore, can I understand like that? Do you really think everybody can afford 64/128GB RAM (mine is 32GB)? Totally speechless. Give us a chance to roll back to 3.7.3, I'd rather to keep it forever until I update to msfs24 to enjoy your brilliant new function.

[DownedAviator]

We did not have these problems at all before 3.7.4 so whatever changed in that version is the issue here.

I have 64GB of ram and 24GB VRAM.

[capt_pero]

[...]
GSX Pro Change: LOD Levels has been changed for ALL vehicles, to take advantage of the different LOD curve introduced with MSFS 2024 SU4, improving object detail in the short/mid distances.

This because we heard so many times users complaining our previous LOD levels were far too restrictive, so we took advantage of the new SU4 LOD curve, which shows better LOD for a longer time in a non-linear fashion, to improve visual pop-up quite a bit. Maybe this new less restrictive LOD is "just" too much for the sim to handle ? Nothing is free is this world: if you hate pop-up like everybody, you must accept the improved LOD would surely take more memory.

Maybe opening the default fps counter and checking your RAM/VRAM situation might be helpful.

Thanks Umberto for investigation. I think it's not worth discussing who is crashing what. The problem is, we cannot use the combination of GSX and AI models (even with VATSIM) any more.

Which logs or data do you want us to collect?

[DownedAviator]

I have to do more testing but if I remember correctly it could have been that the CTDs only started with 3.7.4 when I started injecting traffic. But I dont use AIG, I use FSLT.
The only thing I know for sure is that after uninstalling GSX 3.7.4 I never had any CTDs anymore. And when using 3.7.3 and all my other addons I never had any CTDs at all.

The problem does not seem to be restricted to one specific injector or AI traffic data source for injection. For example this user appears to be using FSLTL for injection of default FSLTL models only. (Not using AIG data).

I inject traffic with AIG Traffic Controller (AIGTC) which only injects AIG model data.

FSLTL can inject  FSLTL and or GSX models

Beyond ATC (BATC) can inject FSLTL and GSX models.

FSHud can be used with various sources, including:

FSLTL
FS Traffic
AIG Traffic
External Traffic: FSHud can also handle traffic injected directly into FSHud through the FSHud REST API.

[virtuali]

Interesting, sacrifice msfs2020 users's simobjects limitation to accomadate a new introduced msfs2024 function, and for those small RAM users even they don't deserve to fly anymore, can I understand like that?

First, this was just a THEORY, which I came out since I cannot reproduce a crash with two different AI injectors, so I tried to assume it MIGHT have been due to just "too much stuff" being pushed, to increase the visual quality.

And no, you are entirely wrong saying we "sacrificed" MSFS 2020 users: LOD it's LOD, the difference it's just what the sim considers a "proper" lod with its diagnostic tool. Our previous LOD levels were reported to be correct by the MSFS diagnostic tools (and users *hated* us for stick to them, now you want to go back...) and MSFS 2024 diagnostic tools UP TO SU4. After SU4, the response to the LODs has changed, so the diagnostic tool in 2024 is still reporting the improved LOD as correct, that's it, but you would see some improvement in 2020 as well, although now the 2020 diagnostic tool would probably report the LOD levels to be out of specs, which shouldn't be a problem, since that's the case for almost every other add-on out there (except GSX): users hate visual pop-ups, so other developers simply don't care about respecting the suggested LOD (as we did), so we were wrongly accused to have bad LODs JUST because we were the only ones fully respecting the direction of the sim own diagnostic tools.

Now, I really not sure anymore if this is the case, as you can see from other posts saying they are getting the crash which I cannot reproduce, with the same memory configuration I have ( 64 GB RAM, 24GB VRAM), so it might not be memory exhaustion after all, but I had to consider this, since it was the only thing that really changed from 3.7.3 to 3.7.4, since interaction with AI (in the Map, which is something new) was already there in 3.7.2.

[virtuali]

Thanks Umberto for investigation. I think it's not worth discussing who is crashing what.

Of course it's worth, that's the first step towards understanding a possible fix, assuming a fix it's even possible, or at least some workaround. Don't misunderstand me: I'm NOT saying this to "put blame on somebody", when there's a CTD, it's ALWAYS something in the sim, since NONE of these add-ons can directly crash the sim, since they are all (GSX and various AI Injectors) external .EXE that can only make Simconnect calls to the simulator, they don't have ANY access to the sim process.

So, it's clearly an indirect effect: some addon makes what is a perfectly legit Simconnect call to inject some object, and it must triggering something in the sim that makes it crash, we cannot directly "fix" this, we can only try to understand WHAT is causing this ( too many objects, too large objects, too many simconnect calls, etc. ) and workaround it.

The problem is, we cannot use the combination of GSX and AI models (even with VATSIM) any more.

I fully understand the problem you are having, which I still cannot replicate. Note that, I must say I tried using the default A320 from iniBuilds, because I always proceed this way: if a report says there's a crash with FSLTL injection + GSX, I first try to isolate that, and proceed by adding further stuff AFTER because if I just test something with "everything in", it would be almost impossible to understand the real cause, which might as well be a combination with even more factors, like the *combined* effect of AI Injection+GSX injection+Airplane own Simconnect calls, and of course the baseline increased memory usage of a detailed 3rd party airplane.

So yes, of course I'll try to do the same with several add-on aircraft, trying to replicate the crashes which I'm still unable to, with GSX+FSLTL+BATC+default A320.

Which logs or data do you want us to collect?

I already indicated something that might have been useful in my previous post:

Maybe opening the default fps counter and checking your RAM/VRAM situation might be helpful.

[DownedAviator]

I have 64GB of ram and 24GB VRAM.

I have a multi-display setup, several hardware and software controllers, hundreds of addons, and my settings mostly on ultra. All of which my system can handle with good performance.

Currently I am loaded into the sim using AI traffic and a DELAYED manual start of GSX (after traffic injection) and my system is using 51GB RAM 14.4GB VRAM and averaging around 40% CPU usage.

I did not see any significant increase in VRAM usage when I manually started GSX.

During the initial AI traffic injection process there was no significant change observed in CPU, GPU, RAM or VRAM usage.

I conclude that system performance is not an issue in my case.

So my system is capable of all that but since 3.7.4 if GSX is in the startup sequence in exe.xml it will instantly cause MSFS to CTD as soon as AI traffic injection starts.

[virtuali]

I have 64GB of ram and 24GB VRAM.

Same here, i9 10900, RTX 3090.

Currently I am loaded into the sim using AI traffic and a DELAYED manual start of GSX (after traffic injection) and my system is using 51GB RAM 14.4GB VRAM and averaging around 40% CPU usage.

VRAM usage mostly checks out ( I have 13 GB taken at default KLAX with the default iniBuilds A320 V2 ), but RAM usage in your case seems to be very different, although it would have been useful if you posted a screenshot of the dev mode fps counter, so I can be sure we are looking at the same thing.

if GSX is in the startup sequence in exe.xml it will instantly cause MSFS to CTD as soon as AI traffic injection starts.

Of course I'm using GSX in default mode ( starting with EXE.XML ), and I still can't replicate a crash. See a video I just made, now with the Fenix A320, at default EDDF, using FSLTL models and Injectors, my settings are Ultra preset EXCEPT for all default AI traffic disabled, so the only AI generated are coming from the Injector.

https://youtu.be/ll3EH7cCDck

Now, please let me clarify this: I'm not trying to "deny" some users are affected, the whole point of the video is to show:

- The problem is not easy to reproduce as it seems

- I'm working at it, doing tests.

Now, for full disclosure, I'm running a slightly updated version of GSX, that contains some fixes for some likely (but maybe not) unrelated problems with .NET. They should be unrelated, since they would happened with 3.7.3 as well, but in case they are, I suggest trying the Beta updater I posted here and see if it makes any difference:

https://www.fsdreamteam.com/forum/index.php/topic,33890.msg213168.html#msg213168

[DownedAviator]

Yes my RAM usage is high at the moment simply because I happen to be running a load of other things at the same time as the sim at the moment, including multiple MSEdge open tabs. Although it is better not to do that for performance reasons my system handles it and that is not typical usage when I am using the sim.

So even with nothing other than what is required for running MSFS I still get the GSX problem, so it makes no difference in my case.

By the way, it is normal and recommended practice to disable MSFS default traffic when using third party injected traffic.

[virtuali]

So even with nothing other than what is required for running MSFS I still get the GSX problem, so it makes no difference in my case.

Have you tried the updated version I posted ?