Garbage Collection Stuttering got worse in 1.1.1

[Broco]

I just downloaded 1.1.1 and tried it out and noticed that the GC stuttering got significantly worse, it now occurs almost twice as often for me. I went and removed all mods (just had only environmental mods like chatterer, scatterer, eve and planetshine) just to make sure it wasn't incompatibility-related, even removed GCMonitor but it didn't get significantly better.

Actually, the game has now officially entered the unplayable state for me. In 1.1 it was really, really annoying but it's unbearable in 1.1.1.

I can't understand how this can't be addressed with high priority, there are so many people that are affected by this bug and it has been reported multiple times. Seriously, I can avoid destroying my buildings with wheels by just NOT CRASHING INTO THEM but I just cant do anything about this constant stuttering.

So please @SQUAD , either pressure Unity to make their garbage collection more adjustible or write your code so it doesn't trigger the GC that frequently (aka create less garbage). There is enough info on how to handle the Unity GC:

https://www.pluralsight.com/blog/software-development/unity-tips-and-tricks

http://stackoverflow.com/questions/17481863/unity3d-optimize-garbage-collection

http://www.gamasutra.com/blogs/MeganHughes/20150727/249375/Unity_Garbage_Collection_Tips_and_Tricks.php

 

I really, really can't understand why you don't adress this issue with the highest possible priority. The game is broken for me right now. I know I have it more frequent than most people but I noticed this very problem in countless KSP youtube videos.

I made one on my own to point it out:

http://www.youtube.com/watch?v=nq0Z2Up1_Uw

Examples (just so you know I'm not making things up):

Matt Lowne (0:49, watch the opening doors hang):

 

Also found this in bug in Scott Manley's videos and others. I can provide more video evidence, but I think everyone knows this exists by now and I think it's time to put this on top of the TODO-list.

I literally CAN'T play KSP anymore at the current state. A ~0.3 second flickering every 5 seconds makes the game more annoying than fun for me.

 

Here one more screen shot with GC-Monitor up:

 

Please @SQUAD, fix this. You did such an amazing job in the past, don't leave me hanging after nearly 6 years I've been with you and your project.

[Sirad]

7 hours ago, Broco said:

I can't understand how this can't be addressed with high priority,

 

I strongly guess this would require a complete rewrite of the code.

Guess what'll happening.

http://bugs.kerbalspaceprogram.com/issues/4051

This is (i guess) the related bug. The Priority is low, it'l may never get fixed. Im not amused as many else are but, we already bought the game so far, this qualifies us as absolute dead weight.

I start to notice the sound of being laughed at for buying a early acess game.

Edited April 29, 2016 by Sirad
angry

[Broco]

4 hours ago, Sirad said:

I strongly guess this would require a complete rewrite of the code.

Guess what'll happening.

http://bugs.kerbalspaceprogram.com/issues/4051

This is (i guess) the related bug. The Priority is low, it'l may never get fixed. Im not amused as many else are but, we already bought the game so far, this qualifies us as absolute dead weight.

I start to notice the sound of being laughed at for buying a early acess game.

I really don't think @SQUAD  see it this way. From a business perspective this would be a suicidal approach because happy existing customers talk positive about your company, thus increasing the number of your customers. Angry customers do the opposite, thus significantly reducing the amount of new customers. I found myself actively telling others to buy this game when everything worked like a charm and I stopped doing so until a gamebreaking bug is fixed. This is just how things go.

So no, I don't think @SQUAD see us as dead weight I just think they didn't get how serious this is and how much it affects players because most people think it's just an issue with their computer.

[Sirad]

1 minute ago, Broco said:

So no, I don't think @SQUAD see us as dead weight I just think they didn't get how serious this is and how much it affects players because most people think it's just an issue with their computer.

Well rising Squad up into the Heavens of Ethic Business like a good Michelangelo Painting doesnt fix that Bug :-)

[d.frison]

16 minutes ago, Sirad said:

Well rising Squad up into the Heavens of Ethic Business like a good Michelangelo Painting doesnt fix that Bug :-)

Agreed, although I also think no company would do this on purpose with it's own public. It's suicidal and would have caused Squad to fail many versions before. Maybe it's just that some things are just too hard to fix and wouldn't pay for the pain, or maybe it's a Unity bug... But some trues just can't be told to the general public, because they would cause unnecessary rage. So documenting the bug and put a low priority on it might be the best option. A word to the wise, however.

[Broco]

20 minutes ago, d.frison said:

Maybe it's just that some things are just too hard to fix and wouldn't pay for the pain, or maybe it's a Unity bug...

Neither of those. This problem and the solutions for it are well known amongst Unity developers. It's not hard but it requires time. And time is money. So unless this problem gets a high priority it will not be adressed.

In my and many others opinion this should have a high priority. But since it's not as evidently a problem of the game as the wheel bugs for example it would require significant development time "just" to get rid of a problem that is not "gamebreaking". Quotation marks because "gamebreaking" is purely subjective and for me it is. I won't touch KSP again until this is fixed and I won't encourage others to buy it as I did before.

Edited April 29, 2016 by Broco

[Festivejelly]

I've noticed this a lot too. Even more so with lots of mods (plugins) installed.

I did some performance testing on the game in 1.1 and found it was mainly the case that mods with plugins (mechjeb, kerbal engineer) impacted the GC delay.

I found without mods the GC is still an issue but it only drops the frames by say 5 for about 5ms. Not noticeable.

However when I enabled some mods such as scatterer, mechjeb and kerbal engineer. Then I started to notice a big impact. Frames were dropping by 30 and were taking 100 - 200 ms to perform the GC.

I guess one thing to remember is each plugin runs its own code so if the plugin creator has been very sloppy in their programming then this will impact the game. However I cant speak for the state of the code for the plugins I use as I havnt looked at the source yet.

My suggestion is to try the game without plugin based mods see what results you get and slowly introduce mods to try and find a balance. Its not a perfect solution I know but you may be able to find a compromise.

Ultimately its down to Squad to fix this issue, Ive played lots of games made with Unity and have never noticed this issue before. I know KSP deals with a lot more numbers than most other games but there's surely steps squad could take to mitigate this. Performance wise for me 1.1.1 is clearly as step back from 1.1. I'll stay with 1.1 for now as the GC issue is just about bearable. As Broco said its unplayable in 1.1.1
 

Edited April 29, 2016 by Festivejelly

[steve_v]

5 hours ago, Sirad said:

The Priority is low, it'l may never get fixed.

Yeah, the most official word I've heard, essentially: "minor issue, better things to spend the time on."

2 minutes ago, Festivejelly said:

I did some performance testing on the game in 1.1 and found it was mainly the case that mods with plugins (mechjeb, kerbal engineer) impacted the GC delay.

Indeed, some plugins appear to make much garbage. I suspect this may improve if/as mods move to the new UI system.
Solutions: a: Make less garbage, both Squad and modders. b: fix the GC, or prod Unity to do so. Don't really see a third here.

Edited April 29, 2016 by steve_v

[vgamble]

I have seen many people complaining on this issue, but never seen it myself. Interesting why a lot of players don't face this problem when others do? My apologise for bad english

[Festivejelly]

23 minutes ago, vgamble said:

I have seen many people complaining on this issue, but never seen it myself. Interesting why a lot of players don't face this problem when others do? My apologise for bad english

Try installing a few mods that have plugins within them. Ive not noticed the issue much with part only mods.

[Broco]

1 minute ago, vgamble said:

I have seen many people complaining on this issue, but never seen it myself. Interesting why a lot of players don't face this problem when others do? My apologise for bad english

It mainly depends on 2 things:

- Mods (amount and type of the mods)

- vessels (how many and how big are your vessels, which parts are on your vessels)

 

If you want to repoduce it, try to send up 20+ vessels with 100+ parts. And I dont mean have them all together in the same proximity, send them all around the solar system so that only 1 vessel at a time is in proximity. Now you should start encountering the problem.

[vgamble]

Just now, Festivejelly said:

Try installing a few mods that have plugins within them. Ive not noticed the issue much with part only mods.

Actually i am RSS-RO player, there is bunch of dll's. But to be honest my 1.1 is clean, don't have played it to much since RO is incompatible at this time, i use it only for testing, so maybe in new ksp things will be different.

10 minutes ago, Broco said:

It mainly depends on 2 things:

- Mods (amount and type of the mods)

- vessels (how many and how big are your vessels, which parts are on your vessels)

 

If you want to repoduce it, try to send up 20+ vessels with 100+ parts. And I dont mean have them all together in the same proximity, send them all around the solar system so that only 1 vessel at a time is in proximity. Now you should start encountering the problem.

I see now. 

[Broco]

Here's another screenshot I made just now. Only mod installed is GCMonitor which shows when the GC becomes active. I also got rid of EVERY mod just for testing purposes and it was the same, except when I used a complete new safe. Every peak you see in this graph is a stutter of about 0.2-0.3 seconds. My normal framerate is also displayed (64.1 in this case), so it's clearly not a CPU/GPU issue.

 

So it's clearly related to the amount of vessels currently in the game, which makes sense in a way.

Here's a screenshot of my Tracking Station with the biggest vessel I have in the game selected (which explodes upon load in 1.1.1 ):

 

[vgamble]

2 minutes ago, Broco said:

Here's another screenshot I made just now. Only mod installed is GCMonitor which shows when the GC becomes active. I also got rid of EVERY mod just for testing purposes and it was the same, except when I used a complete new safe. Every peak you see in this graph is a stutter of about 0.2-0.3 seconds. My normal framerate is also displayed (64.1 in this case), so it's clearly not a CPU/GPU issue.

 

So it's clearly related to the amount of vessels currently in the game, which makes sense in a way.

Here's a screenshot of my Tracking Station with the biggest vessel I have in the game selected (which explodes upon load in 1.1.1 ):

 

Can you share a save file, for testing purposes?

[Festivejelly]

Wow this is unacceptable.

Part count shouldnt matter if the vessles arent loaded in.

clearly there is some optimisation to be done.

[Broco]

3 minutes ago, vgamble said:

Can you share a save file, for testing purposes?

Sure, here's my entire career (copy it into saves):

http://www.file-upload.net/download-11530848/Broco.zip.html

Or just an actual save file if you want:

http://www.file-upload.net/download-11530855/Broco.sfs.html

 

[vgamble]

So i was play with your save files. There is some stutters. Its not that horrible as you described. I can live with that, i actually barely notice them. Also i have different numbers in GCmonitor, stutters shows when "mono alocated xxxxxx MAX" goes to ~1400mb and then resets. First i loaded biggest ship i find in your career, ~450 parts or so, i get 25-30 fps, barely noticeable stutters of GC, i crush it several times "In the name of SCIENCE", and revert fly 3-4 times. second ship - i forgot partcount, i think ~200+, 45fps, don't notice any stutters at all. I will try to post some images 

1 hour ago, Broco said:

Sure, here's my entire career (copy it into saves):

http://www.file-upload.net/download-11530848/Broco.zip.html

Or just an actual save file if you want:

http://www.file-upload.net/download-11530855/Broco.sfs.html

 

 

[Festivejelly]

@vgamble what spec machine you using?

mines:

windows 10

gtx 970

16gb ram

3.5 ghz i5

Edited April 29, 2016 by Festivejelly

[Broco]

12 minutes ago, vgamble said:

So i was play with your save files. There is some stutters. Its not that horrible as you described.

Did you use the file with all vessels in flight? Because if I just launch certain vessels of mine in a clean safe this problem doesn't occur as much, just with having my ~20 flights in progress at the same time. The vessel size doesn't matter. In fact it becomes more obvious if you use a smaller ship like the small SSTOs.

And maybe I should post my specs:

Intel Core i7 3770K (3,5 GHz)

16 GB Ram

AMD Radeon R9 200 Series (3 GB)

 

Though the specs shouldn't have much impact on the GC calls.

Edited April 29, 2016 by Broco

[Festivejelly]

True they shouldnt really. Ill do some more testing when I get home from work. Seems like having more vessles has a greater impact. Suggests ksp isnt handling resources very well.

[steve_v]

1 hour ago, Broco said:

Or just an actual save file if you want:

Yup, I see the stutter here clear as day - I wouldn't want to play that save TBH.

Here's a little vid, even at the low framerate of that capture the gameplay impact is obvious. I'm pretty sure this has gotten worse since 1.0.5, it certainly hasn't got any better.

No mods bar GCMonitor, BTW.

Debian GNU/Linux 8.4, I7-3820, 16GB, GTX680.

Edited April 29, 2016 by steve_v
Stupid editor.

[Broco]

6 minutes ago, steve_v said:

Yup, I see the stutter here clear as day - I wouldn't want to play that save TBH.

Yes but the save worked like a charm till 1.1 came out. Yes, the framerate was worse especially on big vessels but it was way more playable than now. And I guess you can understand that I don't want to throw that save away because I put a lot of effort into building all that up, it's not like you can build all those vessels and position them in about 1 hour, this is like a months or 2 of "work". If I can't play that save, I won't play at all, because this is MY space program.

If this isn't fixed it's goodbye KSP for me. Period.

But I'm glad to see that it's not my computer. And I'm sad to say it but this is inefficient programming at its finest.

Edited April 29, 2016 by Broco

[vgamble]

I use save with career, ships on orbit 

39 minutes ago, Broco said:

Did you use the file with all vessels in flight? Because if I just launch certain vessels of mine in a clean safe this problem doesn't occur as much, just with having my ~20 flights in progress at the same time. The vessel size doesn't matter. In fact it becomes more obvious if you use a smaller ship like the small SSTOs.

And maybe I should post my specs:

Intel Core i7 3770K (3,5 GHz)

16 GB Ram

AMD Radeon R9 200 Series (3 GB)

 

Though the specs shouldn't have much impact on the GC calls.

3570k 4.4ghz, 8ram, r9 280x, no ssd, win 7 64

 

42 minutes ago, Festivejelly said:

@vgamble what spec machine you using?

mines:

windows 10

gtx 970

16gb ram

3.5 ghz i5

 

also, game settings - all max in graphics, 1440p, 2x aa, vsync ON, in general i disable "space centre crew" - but this have nothing to do with stutters in fligh, only helps in VAB-SPH, no opengl, d3d parameters

 

Edited April 29, 2016 by vgamble

[steve_v]

7 minutes ago, Broco said:

If this isn't fixed it's goodbye KSP for me. Period.

Don't hold your breath. Others, myself included, have spent considerable time tracking down the cause of this (there's even a mod just for the purpose - kinda indicates it's a widespread issue, no?) and all we've heard from Squad so far is head-in-sand.

I guess nobody on the dev team tests with large saves, or surely someone would have encountered it by now.

As it stands, I consider late-game (still) effectively unplayable due to this, mods or not. The overall improved physics performance in 1.1 just serves to make the GC pauses more obvious.

Edited April 29, 2016 by steve_v

[steve_v]

31 minutes ago, Broco said:

And I'm sad to say it but this is inefficient programming at its finest.

This is Unity, the cheapest game-engine on the block.

Squads code may well be inefficient, but Unitys GC is also pretty horrible... mainly because Unitys mono fork is ancient, and they won't update for "licensing" reasons. Reminds me why I hate dealing with commercial entities that swipe, then butcher open-source code.

That said, there are plenty of things Squad could do to alleviate the effects on gameplay, as you have already covered. It's getting to the point where someone really needs to do something, but that somebody isn't you or me unless Unity and Squad release their source code.

Edited April 29, 2016 by steve_v
Okay, two posts it is. This editor is bung.