FPS drops after each consecutive launch. (1.3.1)

[Kilhmar]

Hi all! Completely stock install (1.3.1). GFX-options to full screen, full res textures, very low aero-fx, no fps limit and 2x AA. For each consecutive launch of a craft the FPS drops; from 80+ during the first launch down to less than 20 after a few launches. See video. Win10 X64, Ryzen 7 1800X, GTX 1080Ti, 64 gigs of RAM.

 

 

Edited November 17, 2017 by Kilhmar

[Rocket In My Pocket]

Haven't heard good things about Ryzen and KSP. KSP is highly single core performance bound (Like every video game really.)

Combined with the well known memory leaks/Unity garbage collection issues, what you are saying is pretty normal imo.

Good news is the update to Unity 2017 in KSP 1.4 may help alleviate this somewhat.

[Kilhmar]

Not like every video game really, but that's a different discussion. The Ryzen easily runs KSP at 80+ fps on my rig, on the first launch after reloading the game again. And this has nothing to do with garbage collection or memory leaks. The FPS reduction is constant, not stuttering, and mem usage does not change noticeably. Ran MemGraph on my install and had no garbage collection issues.

[HebaruSan]

You should consider posting this on SQUAD's bug tracker:

https://bugs.kerbalspaceprogram.com/issues

Your test case is pretty good, very simple and focused, which means it would be easy for SQUAD to try it, and if they see the same problem, they might be able to fix it.

[Rocket In My Pocket]

12 minutes ago, Kilhmar said:

Not like every video game really, but that's a different discussion.

I mean, you just can't really multi-thread physics well, that's just a general issue as opposed to being particular to KSP and/or Unity.

Most players complain about performance getting progressively worse over time played, especially when reverting a lot. It's something even I've noticed.

Your case may be worse for some reason though certainly; make a bug report as @HebaruSan suggested. No harm in it.

[Kilhmar]

9 minutes ago, HebaruSan said:

You should consider posting this on SQUAD's bug tracker:

https://bugs.kerbalspaceprogram.com/issues

Your test case is pretty good, very simple and focused, which means it would be easy for SQUAD to try it, and if they see the same problem, they might be able to fix it.

Will do. Thanks.

[Kilhmar]

12 minutes ago, Rocket In My Pocket said:

I mean, you just can't really multi-thread physics well, that's just a general issue as opposed to being particular to KSP and/or Unity.

Most players complain about performance getting progressively worse over time played, especially when reverting a lot. It's something even I've noticed.

Your case may be worse for some reason though certainly; make a bug report as @HebaruSan suggested. No harm in it.

 

I'm not going to debate the pros and cons of parallelization of physics calculations. The fact is that my CPU has no problem running KSP at 80+ FPS on the first launch of a new game, and the first launch of loading a saved game. This has nothing to do with physics calculations. After running it down to less than 20 FPS in the last video I simply restarted KSP, loaded the saved game, and launched again with 80+ FPS.

 

 

[Rocket In My Pocket]

What I'm telling you is that this is a common issue. Every ones performance get's worse as they play the game, especially when doing lots of reverts.

Same thing happens when I restart my KSP, performance shoots back up. It's kind of a known issue. I can't really say whether what you are experiencing is any worse/better than the average. Just letting you know it isn't just you.

Here's a relevant thread about Ryzen in particular with Dev response.

 

Edited November 17, 2017 by Rocket In My Pocket

[Kilhmar]

The i5-3570k does not outperform a Ryzen 7 1800X, even on a single core. Stop trying to make this about the CPU. It's irrelevant.

 

http://cpu.userbenchmark.com/Compare/Intel-Core-i5-3570K-vs-AMD-Ryzen-7-1800X/1316vs3916

[Rocket In My Pocket]

12 minutes ago, Kilhmar said:

The i5-3570k does not outperform a Ryzen 7 1800X, even on a single core. Stop trying to make this about the CPU. It's irrelevant.

 

http://cpu.userbenchmark.com/Compare/Intel-Core-i5-3570K-vs-AMD-Ryzen-7-1800X/1316vs3916

No need to be defensive about it?

Here's another guy with a Ryzen and the same problem though so it could definitely be CPU related. Perhaps the "bug" is particular to Ryzen architecture?

 

Edited November 17, 2017 by Rocket In My Pocket

[Kilhmar]

Why don't you just repeat my very simple test and see if you get the same results? I assume you're not on a Ryzen system.

[Rocket In My Pocket]

Just now, Kilhmar said:

Why don't you just repeat my very simple test and see if you get the same results? I assume you're not on a Ryzen system.

I've mentioned several times that my performance drops with every revert, I've never honestly payed that much attention to it and I'm not sure how quantifying by exactly how much will help you?

I can definitely tell you that after a couple of hours of playing my CPU and RAM usage goes way, way up though.

If it'll help you in some way I'll certainly run a quick test and check the exact numbers in a bit?

[Kilhmar]

After doing some more testing I can confirm that simply moving back and forth from a vessel and KSP Space Center or the Tracking Station will trigger the same bug and tie up some CPU resources. Simply switching between vessels in the map view will not trigger the bug. Exiting to the main menu will release the CPU load. So basically I'll have to exit to the main menu and reload the saved game every time I visit the Space Center. I also get 25-30% more FPS (100+) if I launch from inside the VAB rather than from the launch pad menu. The bug is likely somewhere in the KSP Space Center scene-change to the vessel where some process is not released when it should be..

[Kilhmar]

Yup... The problem is definitely in the Space Center scene. Simply launching via the VAB mitigates the problem.

 

 

[Shadowmage]

1 minute ago, Kilhmar said:

Yup... The problem is definitely in the Space Center scene. Simply launching via the VAB mitigates the problem.

Very interesting; please make sure to include that information in the Bug Report, as that will be extremely helpful to the devs' in tracking down the source of the problem.

Also explains why I've never seen this particular issue as I always launch from the VAB as my craft are all one-off designs.

[Kilhmar]

2 minutes ago, Shadowmage said:

Very interesting; please make sure to include that information in the Bug Report, as that will be extremely helpful to the devs' in tracking down the source of the problem.

 

Yes, I've updated the bug report continually with this thread.

[Rocket In My Pocket]

10 minutes ago, Shadowmage said:

Also explains why I've never seen this particular issue as I always launch from the VAB as my craft are all one-off designs.

Same, I don't think I've ever launched from the Space Center scene ever. I forgot that was even a thing.

[Kilhmar]

11 minutes ago, Shadowmage said:

Also explains why I've never seen this particular issue as I always launch from the VAB as my craft are all one-off designs.

 

However you will suffer from this bug whenever you need to use the tracking station to fly a vessel already in orbit. The only way to circumvent it is to launch something (a probe or something) from the VAB/SPH and then switch to the other vessel via the map view.

[Temeter]

That explains some things. This issue is actually really bad, because it can cripple the performance in Realism Overhaul+RP0, which runs bad enough at it's better times. There, you *always* start from the KSC scene if you use it's construction mod.

edit: Yep, starting the same rocket in RO+RP0 from VAB doubles the simulation rate.

Edited November 18, 2017 by Temeter

[Kilhmar]

This bug is ancient... 1.0.5 is the oldest version I have laying about and the bug is there... Amazing that no one noticed it before.

[invision]

ive asked before why the game runs like crap and always got the same excuses about single thread blah blah but yet can run pretty much any other game on ultimate settings. this game is very poorly optimized and runs worse and worse as you play it and find bugs. 

[HebaruSan]

How does the FPS drop compare to launching from VAB and parking the craft within physics range instead of recovering? I wonder if the KSC scene menu is making a phantom copy of the vessel that sticks around in memory using CPU to do physics processing on invisible parts.

[invision]

wow man you are right ive never had such high frame rate, usually it drops to 30 frames or less by this point.

this is max settings not launching from the VAB

Edited November 18, 2017 by invision

[Rocket In My Pocket]

28 minutes ago, invision said:

wow man you are right ive never had such high frame rate, usually it drops to 30 frames or less by this point.

this is max settings not launching from the VAB

I think you've got it backwards? According to the OP the frame rate is supposed to be worse not launching from the VAB? You're saying yours is better launching from the Space Center scene?

48 minutes ago, invision said:

ive asked before why the game runs like crap and always got the same excuses about single thread blah blah but yet can run pretty much any other game on ultimate settings. this game is very poorly optimized and runs worse and worse as you play it and find bugs. 

Other games don't run heavy physics calculations, they hardly touch your CPU. This is more the nature of what KSP does rather than poor optimization. Running some shooter or something on ultimate isn't really comparable.

Edited November 18, 2017 by Rocket In My Pocket

[HebaruSan]

13 minutes ago, Rocket In My Pocket said:

This is more the nature of what KSP does rather than poor optimization. Running some shooter or something on ultimate isn't really comparable.

Nah, this is a bug. It's doing unnecessary work somewhere; recovering and re-launching should reset everything to the way it was at the previous launch.