Why do some have CTDs and Others do not?

Up until yesterday i had only had 2 CTD’s in a year.

Finally decided to try out multiplayer yesterday & have had 3 in the last 2 days.

Well, when crash dumps are enabled they would possibly be located at:

[drive]:\Users\[user]\AppData\Local\CrashDumps

With for example windbg you can take a look at them
And then you will have something like this

My case (without proper investigation by the way, so this is all assumption, which in fact worked out :laughing: )
I have two mods:

  • TBM930 improvement
  • G3000 mod

When i do the following, high possibility for a CTD:

  • Start flight
  • My plane is init with pilot door open
  • Turn on power inside the cockpit
  • Some sound, some stutter, CTD.

Observation:
PFD’s are initializing, MFD is on "press key ↓ "

What did i change when this started.

  • Open front door on init.

Understanding that
CoherentUIGT!Coherent::UIGT::View::InputGroup::~InputGroup
has probably to do with that js stuff ( Coherent GT: Coherent::UIGT::View Class Reference wich comes close but inputgroup looks to be private, but following expected developers paradigm, it’s more or less same purposed with different parameters)

i checked the pfd/mfd what’s different with an open door.
Well, it’s the message on the MFD the door is open.

So, now when i start my flight, i close the door before powering on, CTD’s gone. As the G3000 is a mod in progress, i can live with this.

Edit: upload correct image.
Edit 2: It also does not CTD when

  • Start flight
  • My plane is init with pilot door open
  • Turn on power outside the cockpit (there looks to be no visual draw event? not sure how this is implemented)
  • Some sound, some stutter, CTD.
1 Like

I agree totally with that. Never had a single CTD since 1st release, and flying in a “stock” rig.

As you no doubt know, you can go View-Disassemble and see the Ops codes around the one that cause the CTD, Might give you a little more information.

There is another explanation to these CTD: the C++ compiler Asobo is using!

From time to time, Visual Studio compiler updates are correcting code-gen bugs. For those not knowing, these are bugs in the compiler causing bad or mal-formed operations on the CPU. It is very hard to spot and usually you’d expect the compiler codegen to be exempt of any such issues, but this slips in from time to time and when it catches you, expect long hours debugging.

I’ve noticed for example the latest SDK docs indicate it is now using LLVM 12. Unsurprisingly, the latest(s) Visual Studio 16.11.x now ships with LLVM 12 as well.

Here are two codegen bugs which are now corrected in 16.11.x but weren’t yet with 16.10.xx…

These two are really severe and actually I have been thinking for a while, because of the seemingly random and non-reproducible nature of many reported CTD, that there is a chance a number of them are due to multi-threaded code bugs. It happens the _InterlockCompareExchange64 intrinsic is one such intrinsic which can be useful in MT code.

Nevertheless, even if the bugs above are for 32 bits codegen, these can happen at the compiler level and it is possible there are others with the 64 bits codegen which are undocumented yet and causing a whole lot of inexplicable issues at runtime.

3 Likes

Agreed. Here’s what I posted on YACT (yet another CTD thread - Ctd hell! - #2 by trgz):

I have a PC that is littered with SDKs of various languages (C#, VB, Perl, Python, SQLLite, Unreal, yada yada); a couple versions of MS Office (2010, 2013); three versions of Visual Studio; around 150 installed games (>100 on Steam alone); dozens upon dozens of apps from many companies (iTunes, Google Earth, Photoshop, Garmin, FiiO, Comodo, AVG, Splashtop, Firefox, Chrome, Putty, Blender,…); several DosBox programs and a few emulators; Uplay, Epic, Steam, Origin, GOG, Rockstar launchers; numerous symbolic links/junctions; and, apart from a recent series of CTDs where I’d accidentally deleted my pagefile (I was moving it from one partition to another - did I mention I have >9 partitions across 6 drives?!), I’ve not experienced any real issues with MSFS 2020 even when running multiple applications - hell, I’ve even been defragging, ripping CDs, updating Steam games, and such, whilst running MSFS (and alt-tabbing between them whilst doing so). And I’m ‘only’ running an i5-9600K and a RTX2060S with 16GB of RAM

What I didn’t mention there were the G27 pedals (using UJR), Rift CV1, ye olde MS stick and occasional FaceTrackNoIR use. My ‘rig’ is far from clean and really ought to be the first to crash.
Oh, and a mere 750W PSU that is actually far above my requirements (I actually used to run two GTX 560Tis with it). And a system controlled pagefile sat on the dedicated MSFS2020 SSD partition (not the boot partition).

I keep getting a problem where the game will just not start. The window appears, turns black and vanishes. Some days it does it more than others. Some days, not at all. Weird shizzle.

Perhaps perhaps … but It work for me :slight_smile: You can try too

Yesterday, I could not start the game at all.

Always about a minute into the load, crash to desktop. Only after disabling virtual memory / pagefile (?!?!??!) and removing Windows Updates KB5005033, KB4023057 did I reach the main screen and run a flight. (Nvidia drivers 471.68, which so far have been superb across the board on 3080ti.)

Community folder items? Not a factor here; 20 minutes of repeated attempts while that folder was empty. No problems after items were restored there.

Hi NG722C,

Long time no ‘speak’ - I learned many moons ago to stay away from this forum, my loss.
However, I trust I find you well.

I have read a good part of this, your thread, with interest and clearly there are many and varied
reasons for CTD’s. Some more salient, perhaps, than others.
So, here are a couple of ‘good’ candidates of my own:

I get an instant, easily repeatable, CTD if I set my rolling cache to even so much as a byte bigger
than the size of the RAM disk that serves it.

I cannot so much as start a flight from Schiphol [EHAM] airport unless I lower the setting:
‘Airport Vehicle Density’ to 50. Set to 50 [or less] I can load and launch without issue.

Both of these examples [the first one in particular] are strongly indicative of CTD’s the
cause of which are buffer overruns.

I hope my observations add in a positive way to what has become a veritable
cornucopia of a thread.

Regards.
See you in another 1000.

The updates will be downloaded again if you remove them.

In case someone sees this and it’s a lifeline: The vast majority of my own CTDs (occurring every playthrough during the Winter) were solved when I increased the Windows pagefile size, because I only have 16GB of RAM.

I was literally at my wits end, then I saw this recommendation elsewhere and I tried it as a last resort, not having touched pagefile sizes since the days of Windows 98!

1 Like

For those that remember the TV show Ali McBeal
John “The Biscuit” Cage: quote:

======" I like a fresh bowl."=======

,
,
,
Well, I like to start of my PC boot with a “Clean Virtual Memory

How to Clean Virtual Memory

  1. Open “run” and type regedit.

  2. Search for HKey_Local_Machine/System/Current Control Set/Control/Session Manager/Memory Management.

  3. Right click on ClearPageFile At Shutdown and put value to “1”

  4. This will clear your virtual memory each time you shutdown your computer.

As always : Take care when using REGEDIT !!!

I was getting quite a few CTD’s and there were 2 changes I made and since the past week (touches wood) I have not had any at all!

  1. I spent a moment and sorted out my community file. I had a lot of junk in there and some of the items were not compatible with the update 5.

  2. This is the most important one - I accessed the performance settings and reconfigured the existing paging files. Just search “paging file” and there’s plenty of posts relating to the issue.

Hope this helps.

Fixed “big” size is best IMHO and cleared every time you shut down.

What would you recommend as a paging file size with 32GB of physical RAM? I have never had CTDs in MSFS, but would like to optimize my paging file, since my MSFS computer is pretty much dedicated just for flight sim use.

Unstable overclocks or mods. 99% of them.

Not smart nor necessary. Not sure if you think that basic security best practices are somehow going to mess with the sim.

I run my Windows 10 (soon to be Windows 11) machine with the firewall enabled, with Defender enabled for real time scan and I do on demand scans weekly. I exclude the MSFS process, and have had zero CTDs or other issues.

No offense, but it amazes the lack of technical knowledge and almost “computer voodoo” we see, that users think prevent issues. It’s like saying “I left the front door to my house wide open, with my cash sitting on the table, and I haven’t had any house fires…not one.”

I have 32GB ram, and because I have two 1TB SSD drives, I set a 32GB Page file on the non OS drive, and set it fixed at 32GB (and have Windows clear it when I shut down, so it is always "empty when I restart FS)

This was more important back in the days of Rotating Drives ( access time, fragmentation etc), so I don’t know how much you gain with a SSD, but I am assuming having the Swap Drive on the non-Os drive, may still be an advantage.

I am always open to other suggestions or comments :slightly_smiling_face:

1 Like

I can report two CTD’s this week… unusual for me… both occured when returning to main menu. One was after landing somewhere in the wild, second was after Nice landing challenge. The CTD came within seconds of clicking the option. No wait screen with blue progress bar was presented.