How much 'stuttering' do you experience in MSFS?

[Noel]

I'm obsessed w/ this issue having had fabulously stutter-free performance for most of MSFS life until some months ago when subtle stuttering of varying quality slowly ensued and I essentially just put up with it as the deterioration was subtle over months.  This came to a head a month ago or so when I installed Bijan's most recent release and that seemed to add enough degredation in performance that it prompted me to start fresh with a complete reinstall of Win 10 and MSFS.  I began getting hard pauses after this which traced back to my forgetting to disable the Win 10 desktop slideshow.  I did a lot of troubleshooting and testing trying to get rid of ALL stutters that were not tied directly to overtaxing of the main thread.  After a few weeks of trial and error troubleshooting I can attest I have nearly 100% stutter-free animation now, better than ever.  It is common even with intense scrutiny to see zero or just one or two brief stutters during an entire 2h flight.  I just did KBWI to KISP in the CRJ700 and witnessed zero stutters of any kind from gate to gate:  total fluid smoothness at 30FPS where I am locked.  I think it's quite possible the quest for higher frame rates may well be driven more by subtle microstutters one is exposed to and less by low frame rate per se, with the assumption that increasing frame rate becomes the pathway to smooth flight.  While it likely is true more processing power can offset some sources of stuttering, I can attest at 30FPS with zero stutters of any kind that there is really nothing lacking in terms of smooth, fluid animation now.  When either CPU or GPU is not taxed/maxed, which will of course jeopardize smooth animation, there historically have been other sources of microstuttering, including ATC text flow and previously the white logging spinner (lower right part of the display) was a culprit but the latter was addressed some SUs ago.  And of course myriad other potential sources of stuttering from outside the sim--this is what I'm focused on here, distinct from simply using settings too high for conditions.

As you scrutinize for stuttering look closely from gate to say a few miles out from arrival landing, so during taxi after pushback, during turns, during ATC speech, etc etc.  I mention a few miles out because this is where it's common to have the main thread become overtaxed esp if T-LOD is set higher than your hardware can cope with, on top of Realtime Traffic and so forth. 

Please vote on this after you've had a hard look.  EXCLUDE stuttering coming from inability to maintain the locked frame rate by Vsync or other as that is predictable and is typically resolved by adjusting settings and/or obtaining stronger components.  There are other questions not about stuttering per se if you care to respond there.

Thanks!

Addendum:  I created this poll to assess if it's worth reviewing the various things I did to get me to stutter-free animation.  The sim has become an absolute joy for me once again!  Could well be that most people do not have issues w/ stuttering but I don't know that to be the case so wanted to ask.  The thread can be used to share findings of troubleshooting and optimization.

 

[Cpt_Piett]

Suffice to say I have not reached Nirvana yet in terms of a 100% stutter-free experience. Having said that I'm happy that the sim is running smooth most of the time. It was hard to answer these questions as it completely depends what and where I'm flying. Final approach to KLAX in the Fenix is completely different from a GA flight in Alaska. 

Most of my flying these days is GA. I'm running 4K, G-Sync and a TLOD of 150 (most of the time). FSLTL for AI traffic. I would say I get stutters 4-6 times during a 1-2 hour flight, although that's probably a wild guesstimate. It also depends what sort of stutters we're talking about. Microstutters, "hard stutters" or pauses? 

Anyway, with a TLOD of 150 I'm only mainthread limited in the most heavy scenery. If I can avoid being mainthread-limited, I'm generally stutter-free. That's my general rule of thumb anyway. 

[sniper31]

I am very happy with my MSFS performance experience as of late. I take a multi faceted approach to improve my simming experience. That is I upgrade my hardware often (after TONS of research). Sometimes I have top of the line stuff, other times some compromises are made due to budget or info I have discovered during research and I end up upgrading close to top tier levels. I am by no means a rich person (I am retired enlisted military after all), but I know how to budget well for my chosen hobby. That all said, I don't believe in just throwing raw horsepower at my sim. I also believe in using balanced settings within the sim (MSFS in this case), ensuring my Windows platfrom is running in a streamlined state, and also really looking at my entire hardware setup. A very good case where I start. I ensure ALL of my components compliment each other. That is case, PSU, RAM, MB, CPU, GPU and cooling. I like to run high end CPU's and GPU's so excellent cooling is imperative. And like Noel, I live in Colorado which is a very cool state year round, and my flight sim setup is in my basement which is extra cool. Still, I run an Arctic Liquid Freezer II 420mm AIO cooler. Cool, cool, cool is the theme. My case is a Fractal Torrent, one of the best cases for airflow. An excellent cooling setup is my base, and in that way I can get much out of my hardware without pushing it to the extreme edges of the envelope when simming. Also of importance to my setup is that I run in 1440p on an super ultra wide curved screen, and I mean ULTRA wide. It is a Samsung 49" Odyssey Super Wide display, with a refresh rate of 240Hz. It is a G-Sync and Freesync capable display. Partnered with my 5800X3d and 3090Ti I am able to fly the PMDG 737 and FENIX A320 all over the place, into heavy loaded airports. I do NOT run AIG AI though. I DO run FSLTL, but I keep my numbers of AI down to manageable levels, my TLOD sweet spot is 175 and I run at 5120x1440 resolution, which is the native res for my Samsung display. My MSFS settings are a mix of Ultra, High and Medium, mostly High though. The settings I have on Ultra are Terrain Vector Data, Volumetric Clouds and that is all. I run at 50% of Monitor Refresh Rate, and that is the sweet spot for MY rig where MSFS runs balanced, in the green. In Developer mode, my system bounces back and forth from GPU to CPU limited. It does not linger on either for more then a second. This is as fine tuned as I have gotten my setup. My MSFS sim experience as a result is very smooth, no stutters that I can detect and absolutely gorgeous. I don't know what my FPS is because I don't pay attention to it that often, but it is around 60-65 FPS when sitting at a busy, large airport in the 737 or A320. CPU temps average at around 53 degrees Celsius in this scenario and when flying. 

That's about the best I can offer. My overall point is balanced settings based on YOUR hardware, and ensuring that hardware components compliment each other, from one end of your system to the other.

[Noel]

11 minutes ago, Cpt_Piett said:

Suffice to say I have not reached Nirvana yet in terms of a 100% stutter-free experience. Having said that I'm happy that the sim is running smooth most of the time. It was hard to answer these questions as it completely depends what and where I'm flying. Final approach to KLAX in the Fenix is completely different from a GA flight in Alaska. 

Most of my flying these days is GA. I'm running 4K, G-Sync and a TLOD of 150 (most of the time). FSLTL for AI traffic. I would say I get stutters 4-6 times during a 1-2 hour flight, although that's probably a wild guesstimate. It also depends what sort of stutters we're talking about. Microstutters, "hard stutters" or pauses? 

Anyway, with a TLOD of 150 I'm only mainthread limited in the most heavy scenery. If I can avoid being mainthread-limited, I'm generally stutter-free. That's my general rule of thumb anyway. 

Really what I am after as mentioned is ANY kind of stutters EXCEPT those directly caused by saturation of the main thread or GPU--I believe these are distinquishable from other potential causes of 'stuttering'.  The latter are easy to pinpoint, are frequently responsive to changes in T-LOD or other variables directly associated w/ taxing the main thread or GPU.  

It appears a strong majority report 0-3 in this hypothetical flight so that is pretty good!  I was "generally stutter-free" for many months leading up to this quest to do better but it's a very different ballgame now with virtually none.  Paradoxically I am leaning more towards a new CPU even though performance in general is better than ever.  It appears the ONLY threat I'm getting right now to completely stutter-free animation everywhere anytime including at complex arrival airports is now squarely aimed at the CPU.  I'm in no hurry and will wait to see how 7900x runs in terms of temperature management.  I'm certain 13900K would get me fully to where I want to be so operating temps are another criteria that matters to me.  I will only do air cooling...

[Noel]

14 minutes ago, sniper31 said:

My MSFS settings are a mix of Ultra, High and Medium, mostly High though.

Howdy neighbor!  Tell me, have you been able to tell what variables impact the mainthread, beyond T-LOD, the most? All my settings are on Ultra but with my lowly 9900K T-LOD needs to be around 100-120 in the PMDG 738 at complex airports like FT's KLAS or KJFK etc.  I had T-LOD at 150 from KBWI to KISP in the AS CRJ7 and had zero stutters from gate to gate and gorgous as can be!

[FBW737]

I wonder if its the same 59% that only get 0-3 instances of stuttering also use "in sim  Vsync". I know it is in my case. That should be telling for everyone.

[GSalden]

My front view server runs completely smooth.

The left view client shows small stutters when banking fast and the horizon goes up/down.

Both only show the outside world .

 

 

[sniper31]

13 minutes ago, Noel said:

Howdy neighbor!  Tell me, have you been able to tell what variables impact the mainthread, beyond T-LOD, the most? All my settings are on Ultra but with my lowly 9900K T-LOD needs to be around 100-120 in the PMDG 738.  I had T-LOD at 150 from KBWI to KISP in the AS CRJ7 and had zero stutters and gorgous as can be!

I can't specifically say which ones affect the mainthread, as I don't keep proper notes on all of my personal testing. I just turn things on and off in different scenarios and run the sim through different situations to see what an impact is. I will say I have learned to ONLY test one setting at a time. 

Also, if I may ask, why are you averse to liquid cooling? AIO (All In One) liquid coolers have been around for many, many years now, and are as trustworthy as any other component in the system. I have not used an air cooler in over ten years, and I have, right now, five desktop computers in my house all running on liquid AIO's of various type without issue. When you start talking about running high end CPU's that generate lots of heat like the new Ryzen 7000 chips or the I9 13900K cooling is even more important and air coolers are not the best option at that point. But, if you just can't trust them, nothing I say will probably make a difference for you 🙂 

You already are aware that T-LOD is the biggest setting that affects main thread. I think also additional things running like lots of complex AI models will affect it. I know that NOT generating ground AI makes a big difference for my system. 

[ppo]

Zero stutter. Frametime is a straight horizontal line.( in MSI Afterburner

 

[Cpt_Piett]

27 minutes ago, Noel said:

Really what I am after as mentioned is ANY kind of stutters EXCEPT those directly caused by saturation of the main thread or GPU--I believe these are distinquishable from other potential causes of 'stuttering'.

Ok got it. I recorded a 1440p video today - short hop in the King Air over the Norwegian West coast. Just re-watched the video and I counted two stutters - otherwise smooth. One was right at the beginning of the video whilst panning in the cockpit - it seemed like the sim wasn't finished loading. The other one just at the top of descent - not sure what the cause was. 

So like I said in the previous post, most of the time I'm good. I've given up trying to land the Fenix at iniBuild's EGLL or KLAX with the full compliment of AI traffic stutter-free though. My CPU just isn't up to it. 

[Noel]

54 minutes ago, sniper31 said:

I can't specifically say which ones affect the mainthread, as I don't keep proper notes on all of my personal testing. I just turn things on and off in different scenarios and run the sim through different situations to see what an impact is. I will say I have learned to ONLY test one setting at a time. 

Also, if I may ask, why are you averse to liquid cooling? AIO (All In One) liquid coolers have been around for many, many years now, and are as trustworthy as any other component in the system. I have not used an air cooler in over ten years, and I have, right now, five desktop computers in my house all running on liquid AIO's of various type without issue. When you start talking about running high end CPU's that generate lots of heat like the new Ryzen 7000 chips or the I9 13900K cooling is even more important and air coolers are not the best option at that point. But, if you just can't trust them, nothing I say will probably make a difference for you 🙂 

You already are aware that T-LOD is the biggest setting that affects main thread. I think also additional things running like lots of complex AI models will affect it. I know that NOT generating ground AI makes a big difference for my system. 

I did some prelim testing when MSFS first came out and never could conclude if most of the other variables under user control have much impact on the MT besides T-LOD!   Yes, RT Online Traffic is a big source of CPU loading.  Right now using Simple Traffic it can come into play so this is a good part of why I'm looking at a better CPU. 

I've always used Noctua air coolers and have always had fabulous results--to me, Noctua is both simpler and there is no risk of any issues with leakage.  I understand leaks are very rare, but do happen.  Plus, w/o custom radiators the AIO's don't perform significantly better than Noctua anyway, in fact many perform worse!.  At least that's what I recall reading in reviews.   But here are a couple of other critical pieces on this for me:

• Often 'noise' is cited as the reason for AIO over excellent air coolers.  This is a non-issue for two reasons:  1, I often use monitor headphones so can't hear fan noise; and 2, when don't have headphones on the audio while flying is far louder than the fans will be.  So this is a complete non-issue for me.
• I pay close attention to where the performance value of adding more core voltage for higher clockspeeds starts to rapidly diminish and stay clear of that, so my cooling needs will be lower than someone trying to squeeze ever bit of performance out of their CPU.
• Like you, my PC ambient air is comes from the basement:  I'm on the first floor but I installed a floor vent (HVAC) directly under my Phanteks PC case which sports 3 intake fans directly over the floor vent, in the case floor.  In the warm summer months I connect the floor vent with a short piece to our complete HVAC system, so pump refrigerated air into the entire case. 

The proof of course is in the results and I've always had really cool running overclocks.  Right now, all 8 cores at 5.0gHz:  CPU core temps fluctuate between 48C and 52C, using CoreTemp.  The only downside for me is the space around the cooler gets cramped, so this means I sometimes have needed to use low-profile DIMMS.

 

[sniper31]

17 minutes ago, Noel said:

he proof of course is in the results and I've always had really cool running overclocks.  Right now, all 8 cores at 5.0gHz:  CPU core temps fluctuate between 48C and 52C, using CoreTemp.  The only downside for me is the space around the cooler gets cramped, so this means I sometimes have needed to use low-profile DIMMS.

Fair enough. My experience is different. I have used Noctua coolers as well, and they are very good. I have two sitting in boxes in my parts closet right now actually. However, I don't like how much space they take up in my PC case. Also, IF one gets a GOOD liquid AIO (right now that would be Arctic or EK) then, in my experience, they cool better then a Noctua or any other air cooler. That said, I think you need a 360mm or 420mm raditor in order to get to that next level of cooling above an air cooler, but not necessarily a custom rad. I have never used a custom rad and I can and have overclocked many a CPU and have never damaged one. That doesn't mean I think overclocking is necessary, I just enjoy doing it. The 5800X3D is not really overclockable anyway. Anyhow, different philosphies on cooling, and there is no right answer as long as one finds a way to keep the temps down, which both of us are acheiving in our different ways. 🙂 

[Noel]

1 hour ago, Cpt_Piett said:

Ok got it. I recorded a 1440p video today - short hop in the King Air over the Norwegian West coast. Just re-watched the video and I counted two stutters - otherwise smooth. One was right at the beginning of the video whilst panning in the cockpit - it seemed like the sim wasn't finished loading. The other one just at the top of descent - not sure what the cause was. 

So like I said in the previous post, most of the time I'm good. I've given up trying to land the Fenix at iniBuild's EGLL or KLAX with the full compliment of AI traffic stutter-free though. My CPU just isn't up to it. 

Sounds like we're pretty much in the same space insofar as stutters go.  I got lulled into accepting the onset of subtle stutters w/o overtaxing of CPU/GPU so right now I'm in heaven again with MSFS it's a total joy now!  This was at FT's KLAS with plenty of RT AI traffic and had one hitch or so right around touchdown then after that back to total smoothness.  You can see why I'm a little on the fence w/ bothering to upgrade my CPU, but I'm still tempted.  There is not the slightest hesitation, lack of smoothness now, even at 30 frames per second.  3440x1440x30FPS is a whole lot less demanding than 4K at higher frame rates.  My next foray will be into FSLTL I think it seems like it isn't going to be more demanding than Simple Traffic near as I can tell, and that you can control density should really solve any issues there.  Do I need every airport to have every gate filled?  Heck no!

 

 

[Ixoye]

The only times I experience a short stutter is when msfs load in some big add-on airports, I use Lod 150 and clouds on high and the rest at Ultra to hold 37-38 fps to avoid stuttering.
1440x3440 V-Sync 50% 75hz

[Cpt_Piett]

16 minutes ago, Noel said:

Sounds like we're pretty much in the same space insofar as stutters go.

I think so. Main thing for me is not to go overboard with TLOD. I find that running it at 150 in most scenarios is okay though. It's a good overall setting. 

I think in another thread we discussed core affinities, and I've experimented further with this. As you probably know I'm using Process Lasso, and I have been for years. I basically make sure that MSFS is exclusively assigned to some cores, and everything else to other cores. In the case of my 12900KF it's fairly simple. I just put MSFS on the performance cores. So that's 8 cores / 16 threads for MSFS (overclocked to 5,1GHz). Everything else of importance goes on the efficiency cores - 8 cores / 8 threads (FSLTL, TDS GTNXi, video recording software etc). I've overclocked the E-cores to 4,0GHz. 

Right now I'm in a hold over YSSY trying to figure out something with FSLTL. Everything is smooth with AI traffic running on the E-cores. Heck, I'm even downloading the whole AIG package in the background - again on the E-cores so not competing with MSFS for resources. It does affect scenery streaming though as my total bandwidth is not enough for both.