Ooooh the lag, ... Let it stop!

[Tom K.]

Hi everyone, so I decided I wanted to make Kerbal space program just that little more realistic by adding the Zoxygene mod and also then having to add Powertech.

My game runs smooth at the highest graphics settings, only this rocket (360+ parts) was so big that only at the launch it was a bit of a very smooth slide-show (about 4 fps), everything was good and playable.

But then it happened ...

I added:

- 11 solar panels

- 3 Big mining drills

- 4 small batterys

- 8 small extra batterys (to the side)

- 8 small fuel cells (to the side)

- 1 Big ZO2 system

All on my lander ...

I was excited for the launch, but my luck was quikly over, while the simulation was loading the terrain, the rocket, everything I noticed how the Alti-meter was out of control, it kept spinning from 01 to 99, then it launched with massive amount of lag, so much lag that the smoke particles began acting weird and worst of all my alti-meter completly broke down with only displaying empty spots instead of numbers.

It was horrible and I had to uninstall the mod, now having some sort of empty feeling ...

2 Questions:

- Are there ways to get rid of the lag, but still keep the high graphics?

- Was the Alti-meter breaking down a part of the mod? (It was a night-launch and I don't know if the instruments require power.)

[Qumefox]

The lag mostly isn't due to graphics.

The problem is that as part count goes up, so does the processing power required. You have to remember that KSP models physics for each and every part on the ship, to be able to keep up with structural stress, collisions, etc. You almost have to think about it like this.. Your not launching one ship. Your launching 360 little ships all ducttaped together. Design optimization is crucial when dealing with large ships to try and get the job done with the fewest parts possible. It sounds like you were borderline to begin with, but when you added the other mods, the extra CPU time needed to run the code in the added plugins pushed you over the edge and the simulation started falling apart.

The faster the processor you have, (and possibly video card, not sure if the game uses physx and offloads some workload to the GPU or not for nvidia gpu's) the larger and more complicated ships you can get away with building before running into problems.

[CkGordon]

I'd recommend that when you get to slideshow mode on your design, you don't say "oh, my computers having trouble running this, lets add more crap for it to process!". That said, 2 big lag makers in my personal experience (and I run a butt load of mods) are struts (they really bog down the FPS and parts count so only use them when necessary) and also there is a thread on here with a settings fix for the kerbin ocean. It helped my game a TON on takeoff. Search for it. But ya, this game is an unoptimized alpha so you have to know your limits on what your computer will be able to handle and stay within them. I went through a bunch of work setting up a mun base only to discover it caused unplayable lag when I started approaching it with mun landers so I uninstalled the game, reinstalled with a fresh persistance file, and only reinstalled the mods and parts that I regularly used. Game starts up way faster now and I don't have nearly as much lag. Once the game releases I'm sure it'll be alot easier on machines but until then, tread lightly. You are dealing with a physics simulation afterall.

[Nooblet68]

The Alti-meter breaks a lot when dealing with heavy lag. I don't know why, but I've observed it happening a lot.

[Tom K.]

I'd recommend that when you get to slideshow mode on your design, you don't say "oh, my computers having trouble running this, lets add more crap for it to process!". That said, 2 big lag makers in my personal experience (and I run a butt load of mods) are struts (they really bog down the FPS and parts count so only use them when necessary) and also there is a thread on here with a settings fix for the kerbin ocean. It helped my game a TON on takeoff. Search for it. But ya, this game is an unoptimized alpha so you have to know your limits on what your computer will be able to handle and stay within them. I went through a bunch of work setting up a mun base only to discover it caused unplayable lag when I started approaching it with mun landers so I uninstalled the game, reinstalled with a fresh persistance file, and only reinstalled the mods and parts that I regularly used. Game starts up way faster now and I don't have nearly as much lag. Once the game releases I'm sure it'll be alot easier on machines but until then, tread lightly. You are dealing with a physics simulation afterall.

Struts ... struts, struts, struts, STRUTS, STRUTS!!!

Okay, I'm a paranoid strut maniac, I think from the 360+ parts about 100 are struts, first gonna clean that up.

Oh, I have one last question:

You said that your Mün-base was a real pain in the *** for your game, does this also mean that the pieces of floating debris in space cause lag-problems too, cause then I just have to clean out my persistence file.

(I'm a total noob at game files and such, how do you know what to delet and not, I don't want to ruin the entire program. )

Edited October 14, 2012 by Tom K.
How do you clean out your persistence file?

[Qumefox]

Lots of debris floating around certainly won't help anything, but it shouldn't hurt much either until you get close to any of it.

Easiest way to clear debris is to go in the settings on the main game load screen. change the 'max persistent debris' slider to zero.. apply and accept, then quit KSP and relaunch it. when you open your save after you relaunch it, all the debris should be gone.

You apparently have to restart the game any time you change the debris slider for the change to take effect.

[Grizzlol]

"More struts!" is not a solution. To my experience, including other games with similar dynamics, adding more constraints only makes things worse. They all pull and tear on each other and will eventually work against each other. I remember playing a physics based bridge building game called Pontifex, in which you add together every link individually. Just like any curious person eventually would, one time I decided to test the limits and put together hundreds of parts together into a very dense cluster. In the simulation, the thing actually imploded, and then the game crashed. I have experienced similar behaviours using struts in KSP, although not as brutal. Also, the weight adds up to a lot. Less is more. Play it smart, not by brute force. Triangle shapes are most efficient in terms of material used versus strength and reliability.

[ameseree]

with my experiences with the zoxygene mod is that the drills cause a lot of lag. I have no idea if that is still present though.

[Tom K.]

Okay, I've brought down the amount of struts and now there are 300+ parts, 50+- struts wich actually didn't really do anything are now history.

I did a test flight (still without the mod) and everything went Smooth.

Off topic

I also found the magical thing about fuel distribution, my ship sometimes randomly exploded while 10 KM in the air, I already had a feeling that it was cause the lower tanks drain first, now I connected the fuel of my outer fuels tanks to my inner, which gives me the chance to also use the inner rockets without wasting fuel, that way the rocket is safer, generates WAY more thrust, I only need half of the thrust the get of the ground in the air I only need a quarter.

My next report will be about how the mod works.

[Markus Reese]

For my rockets, there sort of is a breaking point. Fine fine fine, the urk! lagdeath. This is on full graphics, the objects such as trees/rocks etc, cannot remember the exact option in graphics is what was doing my comp in. Turn them down just a little bit.

[0jam3290]

As long as you aren't 2km away from debris, it shouldn't bother you MUCH.

[Tom K.]

Okay, tested the rocket one more time without the mod and it was about 100 fps, mod installed ... 2 fps, looks like this mod is just to big for my game and my suprisingly strong computer.

I actually am a bit done with this mod and actually all the mods, last days weren't much fun with KSP, now back using the original, unmodded, stock parts, fresh, honest game, just a clean experience.