Is KSP multi-core, multi-threaded or just a normal single thread game?

[Beef_stEw13]

Just thinking between i5-8600K and i7-8700K. One has hyperthreading, one dosen't. Is KSP a multi-thread workload for the CPU (especially when you have like a bunch of mods like FAR, principia, and other physics mods)?

[Chibbity]

Single core per ship.

Multi threading kicks in when more than one vessel is on screen.

[MechBFP]

From what I have heard Unity (the engine KSP runs on) does not really do multi threading very much at all, so there will be limited value in it.

[CalmLlama]

The I7 has other little tricks that an I3 just doesn't have, but an I5 is generally the best for gaming. I use an I7 6800k, but i bought it with a really good MB as a combo for a good discount.

[CalmLlama]

The I5 usually has better per core performance than an I7 too.

I got my MB + CPU on a day after thanksgiving sale combo. They are super common. Sometimes the MB is better in the I7 combo than the I5 combo, and when its a 50% off sale its cheaper to buy the I7 on sale than the I5 not on sale

[Grumpy Old Gamer]

I am wanting to do liquid cooling or cryo in my next build, but all the liquid coolers I can find are passinve circulation, and require fans ont eh radiator, which defeats one purpose of liquid cooling (less noise). So Ill probably end up afro-engineering something.

[Pembroke]

All well and good but I think the unthinkable must be uttered aloud: There are other games, too... <gasp!>

You're buying a computer for gaming and you want to play all kinds of games you like and preferably do so for at least 3-5 years into the future so choose that in mind. If you game then other stuff can pretty much be ignored because most of your computer power goes into drawing triangles, simulating movement of thousands of objects, and loading stuff from the server fast. Whatever spreadsheet usage you may have 1% of your computer can handle that.

It, of course, depends on what kind of games you like, but as a general rule invest in GPU, in "enough RAM", in multiple cores, in Giga-Herzes, in bandwidth, and in "even more RAM". In that order unless you do online gaming a lot in which case bandwidth and net speed go up in the priority list. If ever you've to choose, pick better GPU over better CPU.

Yes, yes, KSP needs CPU. It needs to simulate physics fast. True, and I don't disagree at all. Just reminding that you *may* have some other games you need to also think about, and not just those you play now but those you will buy in 2019 and 2020...

[Grumpy Old Gamer]

Originally posted by Pembroke:

All well and good but I think the unthinkable must be uttered aloud: There are other games, too... <gasp!>

BLASP{HEMER!!!! BURN THE WITCH!!!!

On a serious not though the primary bottleneck in modern systems is the northbridge bandwidth. A great many of them cannot reliably service both the PCI-E buss and the and RAM. Particularly on consumer grade motherboards the chipset rarely has significant northbridge cache space, causing either the graphics bus, memory bus or the I/O bus to stall. In multicore systems, amdahls law dictates that the memory bus must be wider and/or higher clock rate than the individual cores memory bus interface.

[CalmLlama]

I have a 5ghz 220W factory clocked CPU in a Core P3 case, with a 2x fan radiator for the CPU watercooler. It looks really cute wall mounted next to the TV, like geek modern art; too bad it sounds like a leaf blower...

[Smug]

So for some unknown reson KSP will never use more than 1 core unless there are more crafts on screen. So if your CPU is mulitcore, your pretty muched boned if you try and make big crafts, or alot of mods. i have an 8-core but sadly due to the ♥♥♥♥ optimazation it will only use 1 core for huge crafts so i get around 10 FPS when if the game was optimazed well i could get 100.

[RoofCat]

you could probably build the physics interaction code more like vector math works. Adjust block count during launch for optimized performance depending on core count, check total bending index/lowest breaking threshold for each block as a whole, once input happens do the math for whole blocks, send each thread to its core if there is no failure with predicted shifts between them, finish math in multiple cores for each part in each block to do the full animation.

probably™

[CalmLlama]

My FX-9590 runs KSP a lot better than my I7 6800k, and if it were only 1 core per 1 craft that would not be the case. My I7 per core is a lot better than my FX.

[RoofCat]

Originally posted by CalmLlama:

My FX-9590 runs KSP a lot better than my I7 6800k, and if it were only 1 core per 1 craft that would not be the case. My I7 per core is a lot better than my FX.

do you play stock? Also i7 6800k was one of the crapiest Intel chips long before and after. Both 4790K and 7700K are better ones. With Broadwell Intel tried to mimic AMD with stupid wattage, too many badly optimized cores in too small area (my guess) and thus heat throttling and kind of failed.
Still i7-6800k should have been better a bit, but just a bit. Probably some cache or memory speed reasons still make your ancient amd leafblower competitive with the worst intel chip generation lately. i7-8700K generation is the first intel generation where more than 4 cores work like intel chips should.
Anyway both 7700 and 8700 are hitting the same wall already being damn close and I struggle to find reason to change anything if you are close enough except for productivity apps that need more cores.

[Chibbity]

Originally posted by CalmLlama:

My FX-9590 runs KSP a lot better than my I7 6800k, and if it were only 1 core per 1 craft that would not be the case. My I7 per core is a lot better than my FX.

It was in the patch notes of the update (1.1 I'm pretty sure ) that added it way back when they updated KSP to a newer version of Unity.

I'm not making stuff up lol, KSP used to only use one core max, then they added the ability for other cores to take over other ships.

You can't split the physics calculations of a single ship over multiple cores/threads due to how KSP/Unity works so that's how it has to be.

[Pembroke]

All I can say that a six core i9 with 4.8GHz and 32GB seems to run KSP just fine even with all the visual enhancements I added...

[JeQ]

They should fix this. Most of time spacestations gets very huge so putting that all up on single core is very demanding. There must some way them to find how to make it happen. Hopefully unity makes better support for multicore, i would see optimal for kerbal was where all parts are shared to all cores equally except one core. That one core then keeps track of parts that nothing fancy will happen like suddenly spacestations start wobbling and explode.