Part limit and performance

[GoSlash27]

I don't bother upgrading my VAB or pad beyond level 2 in career because level 2 is way more mass and parts than I could ever imagine needing.

Six *hundred* parts?!? Wow! O_o

I have a pretty good gaming setup, and that would reduce it to an oil painting.

Best,

-Slashy

[DMagic]

I have heard, but can't find the source, that certain parts contribute to lag more than others. Docking ports in particular.

Solar panels can have a significant impact. Each one has to be constantly tracking their position relative to the sun and how much power they should be generating. Stick a hundred or so (as compared to a hundred other parts) on an otherwise small craft and you'll a huge difference.

[Just Jim]

My computer starts to get a little grumpy at 250 parts or so, so I try to keep my ships under 200 parts if possible. And my newest station design has only 208 parts.

The worst I've dealt with is having 4 big ships docked to a station at one time... around 800 parts. My computer was not amused.... lol... and you could definitely see a drop in the frame rate.

[BlueCanary]

So do people generally get the green mission clock then? I'm permanently on orange except for occasional green flickers, even on 30 part craft. I wonder how much easier/harder it makes it paying in slow motion.

[Halo_003]

Low part count ships are a challenge. I made a Space shuttle that weighs in at just over 70 parts I think, less than 40 in orbit. My Jool 5 mission measures around 300 parts though.

[Norcalplanner]

If you don't want to use procedural parts, I highly recommend NecroBones' mods, in combination with KJR. Struts almost disappear, and you're able to use fewer, larger parts for big or complicated rockets. The quad nuke from MRS is one of my favorite engines - to get the same thing in stock generally requires 12 parts instead of just one.

[peachoftree]

If you don't want to use procedural parts, I highly recommend NecroBones' mods, in combination with KJR. Struts almost disappear, and you're able to use fewer, larger parts for big or complicated rockets. The quad nuke from MRS is one of my favorite engines - to get the same thing in stock generally requires 12 parts instead of just one.

you can get it in 5 with a quad adapter and 4 nukes.

[Technical Ben]

My computer starts to get a little grumpy at 250 parts or so, so I try to keep my ships under 200 parts if possible. And my newest station design has only 208 parts.

The worst I've dealt with is having 4 big ships docked to a station at one time... around 800 parts. My computer was not amused.... lol... and you could definitely see a drop in the frame rate.

This. My (sandbox) Jool challenge craft was suppose to be 200-250 max parts, but ended up being 301. It will drop a little once the booster/transfer stage has burned it out to Jool. It's kind of the limit on my 5 year old PC.

[regex]

So do people generally get the green mission clock then?

I get green during launches of 100 parts unless I look at the ground/ocean, in which case I always get yellow. The PQS system is a major source of lag on my machine.

[Norcalplanner]

you can get it in 5 with a quad adapter and 4 nukes.

Correct - I should have clarified that I was talking about a stackable upper stage where the stock solution is to go radial with the LV-Ns.

[Rocket Farmer]

I'm honestly don't know what the dIfference for me is but I have only ever experienced a dip in frame rates on my largest vessels. I used to launch pancakes of power measuring 7x7 stacked with 3 tanks on a rocket plus connectors and 8+ struts per column. That was just the lifter which didn't count the actual rocket (let's say 650 parts just for the lifter including the boosters around the outside) . All told I didn't ever notice performance drops till a at least 1,000+ parts but it's still very playable. No think the highest I remember was 1,300ish and I remember being a bit surprised at its sluggishness. I never thought it weird because I saw whackjob going 2,000+ on the forum.

I run totally stock KSP on a custom ordered laptop with a good I7, 32gb ram, Solid state hard drive, 17 inch monitor and very good graphics card. The laptop is about 1.5 years old now. It is primarily used for large excel modelling (100mb+ excel files eat computer power).

[Padishar]

Possible, but I doubt it's significant. The lag comes from the physics calculations at the joints between parts (the only place where physical forces really apply to a rigid body). Because of this, the fewer the parts, the fewer the joints, and the fewer the joints, the less physics calculations your CPU has to do, and that means less lag.

Well, you would be wrong to doubt it. There are various types of parts that cause significantly more CPU usage than others. Docking ports, the claw, solar panels and all other parts that generate or consume resources all use more CPU (in some cases considerably more) than a simple structural part. E.g.

http://bugs.kerbalspaceprogram.com/issues/2858

http://bugs.kerbalspaceprogram.com/issues/5136

I'm sure there were ones specifically about solar panels and docking ports too but I can't find them at the moment. I'll run a decent comparative test later when I'm on a machine that can run KSP well (a 2.16GHz Core Duo laptop that only gets 20 fps with a small vessel sat on the pad doesn't make a good testing platform).

[Mad Rocket Scientist]

Well, you would be wrong to doubt it. There are various types of parts that cause significantly more CPU usage than others. Docking ports, the claw, solar panels and all other parts that generate or consume resources all use more CPU (in some cases considerably more) than a simple structural part. E.g.

http://bugs.kerbalspaceprogram.com/issues/2858

http://bugs.kerbalspaceprogram.com/issues/5136

I'm sure there were ones specifically about solar panels and docking ports too but I can't find them at the moment. I'll run a decent comparative test later when I'm on a machine that can run KSP well (a 2.16GHz Core Duo laptop that only gets 20 fps with a small vessel sat on the pad doesn't make a good testing platform).

It has to do with how big the textures are, too. The flat antennas are legendary for this, they have huge textures, especially for their size.