[REPORTED] Microstutter with SA page selected (DL on only)

[Captain Slow]

Reproducible: 100% on my computer

 

Date: 2018-03-01 2200Z

 

Sim version: 2.5.4.28090 Open Beta

 

Mission:

Any mission where there are targets on the network (donating yourself is enough to trigger the issue),

First discovered on Caucasus Blue Flag Server MP server

 

Steps to reproduce:

1. Enter mission

2. Start up F-18

3. Everything works works fine (about 70 fps) on ground... until

4. Turn on DL + Open SA page.

5. Microstutter from hell :(. Unplayable. See attached frame time graph.

6. Exit SA page and microstutter totally disappears (see frame time graph)

 

Problem:

I cannot play in missions that my squad mates play in if I turn on SA page with DL. I get massive microstuttering. My friends dont have this issue, so I dont really know what to do

 

Later also had a squad mate measure frame time and he does not have the issue (verified with measurement)

 

tried repairing my DCS installation but it didnt help.

 

• The green "Normal Behavior" part of the graph below is when I do not show the SA page.
  
• The red part of the graph below is when I show the SA page.
  

 

 

 

Track:

MP track too big to attach. Attaching single player track instead

 

Screenshots:

Screenshot with frame times attached

Screenshot with ingame graphics settings attached (but later discovered graphics settings dont affect the issue)

 

Desired solution:

Figure out why I cannot use SA page :(

 

SP/MP:

I first discovered this in Multiplayer, but later measured and exactly the same issue is present in single player.

 

System spec:

9900k

32 GB ram @ 3466 MHz

2080Ti

 

dxdiag attached

DxDiag.txt

microstutter with sa page.trk

Edited March 2, 2019 by Captain Slow

[Captain Slow]

Same issue present in single player. The following is from instant action f-18 amraam mission

 

Conditions for the stuttering to activate:

* At least a couple of targets visible on SA page.

* If you are in an empty mission by yourself and no targets on SA page => no stutter.

 

Edited March 1, 2019 by Captain Slow

[Captain Slow]

If it is of any help diagnosing it:

* Pausing the game will remove the stutters.

* Ingame graphics settings has no effect

* CPU affinity has no effect or improvement (tried forcing cores 0, 0+2, 0+2+4+6, 0+1, 1+3+5, and a few other combinations without any improvements)

Edited March 1, 2019 by Captain Slow

[Captain Slow]

* It seems like the stutters are tied to the rendering of the SA page's targets. If I am in a continous turn the targets are only repositioned on the SA screen sometimes (like 4 Hz), and it seems to match exactly the frequency of the stutters.

 

* Windowed/fullscreen/gsync/vsync settings have no effect on the situation

Edited March 1, 2019 by Captain Slow

[Captain Slow]

I have concluded that the code causing the stutters in my single player tests is called by

function SA_FF_Symbol(parent, isOutlined)
.
.
.
end

 

The SA_FF_Symbol function resides in Cockpit/Scripts/Multipurpose_Display_Group/Common/indicator/Pages/MPD/MPD_page_defs.lua

 

If I comment out that function's contents all microstuttering in my single player test stops. This of course also stops any rendering of tracks on my SA page, so it is pretty far from a solution :).

 

And it doesnt exclude the possibility that for example PPLI drawing might still cause stuttering (The single player test mission/instant action aim120 training only has you on blue side, so no other PPLIs available)

 

 

What I really dont understand is why my machine (which is far more powerful than some of my squad mates) stutters badly in ONLY the SA page ... while everyone else seems to be able to play just fine..

Edited March 2, 2019 by Captain Slow

[Eldur]

Now that's a thorough report there... and I first thought it might be "low hardware" until I saw your specs which are basically full AB.

 

Would like to know how to get those frame time graphs though

[NineLine]

 

 

What I really dont understand is why my machine (which is far more powerful than some of my squad mates) stutters badly in ONLY the SA page ... while everyone else seems to be able to play just fine..

 

Yeah, thats the tricky one, my machine is lower spec than yours and I am not seeing this as well.

 

Have you tried the usual suspects like deleting the shader folders and all that?

[Zarma]

Isnt it related to the callsign ?

 

No problem here with way lower spec.

[Captain Slow]

Yeah, thats the tricky one, my machine is lower spec than yours and I am not seeing this as well.

 

Have you tried the usual suspects like deleting the shader folders and all that?

 

 

Fxo and metashaders? Anything else?

[Captain Slow]

Now that's a thorough report there... and I first thought it might be "low hardware" until I saw your specs which are basically full AB.

 

Would like to know how to get those frame time graphs though

 

I use a free program called "Rivatuner Statistics Server". I asked a squad mate to install the same and he had no stutters in his graph ;(

[Captain Slow]

Deleted the following folders without any improvement:

 

• Saved Games/DCS
  
• %APPDATA%/Local/DCS
  
• %APPDATA%/Local/Temp/DCS
  

 

Reinstalling DCS to see if that helps. If it helps, I will track changes to all non-binary files in my DCS installation using a git repo or something :P

Edited March 2, 2019 by Captain Slow

[Captain Slow]

Okay, so: I have now verified the issue to be significantly reduced after reinstalling the game.

 

However what is interesting here is how the reinstalled folder differs from the old folder. Basically there is almost no difference. The following is a recursive diff comparing the two installations (produced with diff inside babun shell).

 

Files /c/DCS/autoupdate.cfg and /c/Program Files/Eagle Dynamics.bak/DCS World/autoupdate.cfg differ
Files /c/DCS/autoupdate.dat and /c/Program Files/Eagle Dynamics.bak/DCS World/autoupdate.dat differ
Files /c/DCS/autoupdate_log.txt and /c/Program Files/Eagle Dynamics.bak/DCS World/autoupdate_log.txt differ
Files /c/DCS/autoupdate_log_old.txt and /c/Program Files/Eagle Dynamics.bak/DCS World/autoupdate_log_old.txt differ
Only in /c/DCS/: dcs_variant.txt
Only in /c/Program Files/Eagle Dynamics.bak/DCS World/Mods/aircraft: A-10C
Only in /c/Program Files/Eagle Dynamics.bak/DCS World/Mods/aircraft: Flaming Cliffs
Only in /c/Program Files/Eagle Dynamics.bak/DCS World/Mods/terrains: PersianGulf
Files /c/DCS/unins000.dat and /c/Program Files/Eagle Dynamics.bak/DCS World/unins000.dat differ
Files /c/DCS/unins000.exe and /c/Program Files/Eagle Dynamics.bak/DCS World/unins000.exe differ

 

No significant binaries differ, and neither do the configs (if you check the autoupdate.cfg for example the only diff is I had more aircraft modules installed in the old installation).

 

However, after reinstalling: My old installation also runs faster (!)

So I think it is safe to conclude it had nothing to do with the actual installed game contents.

 

I am getting somewhat of a PEBKAC feeling here, due to the installation opening the following window :) (reason: the old installation was a copy-pasted folder from a previous computer's dcs-installation)

 

 

I am surprised the game even ran before, if some libraries were missing. I am not a .net (or windows) dev myself so I dont know how windows handles version mismatching in dynamically loaded libraries, but it could have tried to execute certain functions from an older/newer or compatibility version of the library causing certain calls to run significantly slower

 

BUT

 

And this is the important part. The stuttering still exists, even though it is greatly reduced, I actually believe most people are having it, even though most are not sensitive enough to feel it.

 

I do not think a single mfd page of very simple symbology (having built software for several of these instruments myself) is "worthy" of being a significant performance sink in the game/sim. Therefor I would still hope you will look into making the SA page rendering a lot faster (for dynamic objects)

See the new performance results below:

 

MP:

 

SP:

Edited March 2, 2019 by Captain Slow