Performance tweaks for busy missions

[DeltaMike]

Everybody who plays DCS has performance problems in missions that have a lot of moving parts.  VR players have it worse, since we have to render each scene more or less twice. 

All tests done with G2, OpenXR, MR off (FPS allowed to float).  Measurements taken 7,300 feet above Batumi heading north.  

First I wanted to check a few things I haven't tested in a long time:

• Vis range
• Texture quality (including "detail factors," which I assume has something to do with textures)
• Shadows

Baseline tests done in the caucasus "free flight" mission over Batumi.  I started with everything either off, or at its lowest setting, and then tested one variable at time.

To my surprise, texture quality and vis range had no discernible effect on performance.   This probably depends on the GPU I imagine.  People with older GPU's will almost certainly have different results.  Hot tip:  turn down cockpit texture resolution last.  None of those settings seriously affect game play -- the game plays just fine at med vis range for example -- but low cockpit textures look awful.  

I was also surprised to see that tree visibility did not affect performance.  Hooray for the new trees.   They do look pretty cool at high detail factor.  

Next, I tested these variables in a complex single player mission.  I used the Liberation Dynamic Campaign to generate a mission on the Caucasus map. Not the easiest, not the busiest, somewhere in the middle.

Although my GPU and CPU times went up, once again vis range and textures had no discernible effect.  Here, shadows seemed to affect the CPU primarily.  

Finally, I turned all three on (medium shadows, high textures, ultra range) and compared performance running the same mission on my game computer, compared with running on a dedicated server.   I used a Beelink SER3, which is kind of an AMD based NUC computer for this test.  Four cores with a boost clock of 4Ghz, 16Gb RAM and a little touch of Vega.  Nothing to scream about but even that was overkill.  

There wasn't a huge difference in the numbers but enough to keep me consistently above 45fps, which is the secret to life if you're running a G2.  Definitely takes care of the stutters even when you're flying low to the ground.  

Just for giggles, I took a spin over Guam on my server.  That map performs as crappily on the server as it does on the local machine.  Which leads me to think, the main benefit of running your mission on the server is, letting the server handle the scripts.  

 

CONCLUSION

-- Turning off shadows is a quick and easy way to mitigate CPU load as you swap from simple singer player missions to complex environments with lots of moving parts.  

-- If you enjoy playing heavy missions with a lot of scripts running, playing off the dedicated server has something to recommend it.  Doesn't take much oomph to run, you can dust off an old laptop or something.  No problems connecting; I queried the router to see what address it assigned my server, punched that in the multiplayer screen, boom done.  (There are a couple of extra steps involved if you want to play Liberation on your server, hmu with any questions)

 

 

[rcjonessnp175]

High textures has a huge hit in Apache and Syria.  May not necessarily drop fps allot but it brings about major stutter.  Medium textures solves it.

[DeltaMike]

Yeah backing off on terrain textures does the trick on the Syria map. Doesn't do squat on Marianas, which seems to be flogging my CPU primarily.  

Presently testing some monster missions on the Syria map. 

Edited April 13, 2022 by DeltaMike

[rcjonessnp175]

Ya for Syria I’m doing most my scenarios in Iraq around H3,  good performance out in the desert lol

[DeltaMike]

Whoa.  Liberation is basically unplayable in VR on Syria map, CPU times up to 37ms once all the units are up, FPS below 20.  Running it on the server I'm getting CPU time 14, GPU time 16.  

[davidrbarnette]

This one is a hot-button for me. It is embarrassingly easy to set up a dedicated server (even on the same machine) and see a huge performance boost, but there are compromises... for example, everything seems to be either an air-start or a cold start, and in the Apache you can't switch seats. I just don't understand how there is no official solution yet to CPU related bottlenecks where there are simple but compromising workarounds.