KSP Stuttering Issue Mac OS High Sierra

[Lilypad360]

Hello,

I recently installed the new Mac OS High Sierra. After the installation I noticed I extreme stuttering issues that make the game unplayable. Has anyone else had this issue? Is there any fix for it?

[DrLicor]

Hey, yesterday someone else was here with some issues after installing Mac OS High Sierra, I recommend you to upload some logs, make sure some devs get to know about it, so they can look into it. 
 

 

 

 

[Curveball Anders]

It's on the 1.3.1 pre-release bug tracker.

Bug ID #15975

 

 

[DrLicor]

@Curveball Anders ah thanks, couldn't find it yesterday and haven't been locking around today. I will refer to that in the past threads.  

[Wyzard]

Happens to me too.  It looks as if it's switching back and forth between displaying a pair of previously-rendered frames when it should be displaying a new one, which seems like a problem with page flipping displaying the wrong buffer.

One of the changes in High Sierra is that the WindowServer now uses Apple's Metal API instead of OpenGL.  That's a major change in the component that's directly responsible for managing graphics buffers and redrawing the screen whenever something changes, and major changes tend to introduce bugs.  I suspect that this problem may be a bug in the WindowServer's handling of the swap chain when KSP asks it to display a new frame.

[DrLicor]

@Wyzard, but can opengl still be forced like in windows? Otherwise you should try that out, maybe it solves the problem untill the next patch.

[Wyzard]

16 minutes ago, DrLicor said:

@Wyzard, but can opengl still be forced like in windows? Otherwise you should try that out, maybe it solves the problem untill the next patch.

It's not about what KSP uses to draw its own window, it's what macOS uses to actually put KSP's window on the screen.  As I understand it, it's a 2-step process:

• the application (e.g. KSP) draws its window using OpenGL and asks the system to display the new picture.
• WindowServer redraws the screen to show the new KSP window together with any other windows that are visible, and with any visual effects that are applicable (like the way spaces are shown as thumbnails in Mission Control mode).  This step is done using Metal (in High Sierra) even if KSP used OpenGL to draw its own window.

Remember that this is speculation on my part, though — I don't actually know that this a WindowServer bug.  I just think the flickering looks like a page-flipping problem, and WindowServer seems like a likely culprit for that.)

[Samssonart]

I'm also pretty sure this has something to do with either the new APFS file system or, as mentioned before, that Apple is slowly phasing out OpenGL/Vulkan in favor of their Metal API (In fact Vulkan has never been supported and most likely won't). If it's the APFS we may not be able to do anything about it, but even though the default graphics engine is Metal, High Sierra still supports OpenGL, so KSP can likely be forced to run on OpenGL using the -force-glcore argument.

Could someone suffering from the issue try setting the -force-glcore argument to start KSP? It can be done like so on Steam and I believe there's and advanced option in the Launcher for the KSP Store distribution. Also if someone could provide a log from a stuttering KSP on High Sierra that would be most helpful.

[DrLicor]

3 minutes ago, Samssonart said:

I'm also pretty sure this has something to do with either the new APFS file system or, as mentioned before, that Apple is slowly phasing out OpenGL/Vulkan in favor of their Metal API (In fact Vulkan has never been supported and most likely won't). If it's the APFS we may not be able to do anything about it, but even though the default graphics engine is Metal, High Sierra still supports OpenGL, so KSP can likely be forced to run on OpenGL using the -force-glcore argument.

Could someone suffering from the issue try setting the -force-glcore argument to start KSP? It can be done like so on Steam and I believe there's and advanced option in the Launcher for the KSP Store distribution. Also if someone could provide a log from a stuttering KSP on High Sierra that would be most helpful.

That indeed was what I was refferring to. I don't use Mac OS, so I don't exactly know how it does work.

[Kopmatt88]

Hi,

I'm having exactly the same issue. I've read through the above, and I tried using the -force-glcore argument in the launch options in Steam, but that made it no better. I've uploaded .rtf files of the player.log files to Dropbox, the link should be here: https://www.dropbox.com/sh/xxoy7rui5mpq753/AADjmREEFUCbPinoYO1WPzqxa?dl=0

I was running a couple of mods, but I removed them from the Game Data folder after the issue started, and logs above are without the mods. Today was the first time I've tried playing KSP since upgrading to High Sierra. I've tried two other games, both on Steam, and neither have any stuttering problems (Football Manager 17 and Euro Truck Simulator 2). The stuttering is so bad on both the first and second menu screens that the game is just unplayable once you get to KSC and beyond. 

My game version is 1.3.0.1804. I'm running a 2017, 13 inch MacBook Pro with Touch Bar, 3.1Ghz i5, 16GB RAM, 256GB SSD, Intel Iris Plus Graphics 650 1536 MB.

I really hope this is fixed soon as I've finally got a bit of free time and was looking forward to getting a bit further on KSP.

I hope I've included all the right information! 

 

Ps: I don't know if anyone else has come across this, but I tried to use pastebin (following the bug report link above) and the log files were too big for pastebin without a "pro" account, so I had to use Dropbox and upload them that way. Just FYI if anyone else tries to do that.

Edited September 30, 2017 by Kopmatt88
Added PS re: pastebin.

[listrophy]

I hate to be one of those "I really need this, please fix ASAP" people, but........

I'm scheduled to give a talk at a programming conference near the end of October, using KSP as the main interaction mechanism. So.... I really need this, please fix ASAP.

 

(Same issue, just started happening with High Sierra on my 2017 MacBook Pro w/ TouchBar; Intel Iris Plus Graphics 650 1536 MB)

[DrLicor]

On 29-9-2017 at 2:44 PM, Samssonart said:

I'm also pretty sure this has something to do with either the new APFS file system or, as mentioned before, that Apple is slowly phasing out OpenGL/Vulkan in favor of their Metal API (In fact Vulkan has never been supported and most likely won't). If it's the APFS we may not be able to do anything about it, but even though the default graphics engine is Metal, High Sierra still supports OpenGL, so KSP can likely be forced to run on OpenGL using the -force-glcore argument.

Could someone suffering from the issue try setting the -force-glcore argument to start KSP? It can be done like so on Steam and I believe there's and advanced option in the Launcher for the KSP Store distribution. Also if someone could provide a log from a stuttering KSP on High Sierra that would be most helpful.

@listrophy, ah that suck mate, have you tried this? I could be a temporary fix.

[Kopmatt88]

2 hours ago, DrLicor said:

@listrophy, ah that suck mate, have you tried this? I could be a temporary fix.

As I said in my post, I tried the -force-glcore argument on Steam, and it didn’t work. I’ll give it a go again when I can later, but it didn’t fix it the first time. Both .log files (with and without the argument) are at the Dropbox link. I’ve got two other games on Steam, and they work fine with High Sierra. No graphics issues at all.

[DrLicor]

@Kopmatt88, I'm sorry. I've read right past that. It's not about KSP. It's how High Sierra handles the graphis, especially with Unity..

https://forum.albiononline.com/index.php/Thread/58853-MacOS-High-Sierra-Graphics-Glitch/

http://www.techradar.com/how-to/macos-1013-high-sierra-problems-how-to-fix-them

http://bugs.verdungame.com/topics/1162-graphical-bug-macos-high-sierra/

[Lloigor]

Hi,

https://forum.unity.com/threads/unity-and-macos-10-13-high-sierra.474527/

the problem is caused by the new APFS which is automatically installed on every High Sierra machine with an SSD.

You could try a workaround:

Create a new partition with the "Mac OS Extended" file system. After that just drag and drop your KSP installation into that partition und try to run the game. 

I would try it myself but it seems to work fine on my machine ...

 

[listrophy]

4 hours ago, Lloigor said:

Hi,

https://forum.unity.com/threads/unity-and-macos-10-13-high-sierra.474527/

the problem is caused by the new APFS which is automatically installed on every High Sierra machine with an SSD.

You could try a workaround:

Create a new partition with the "Mac OS Extended" file system. After that just drag and drop your KSP installation into that partition und try to run the game. 

I would try it myself but it seems to work fine on my machine ...

 

Moving the KSP installation to a brand-new "Mac OS Extended (Journaled)" partition did not solve the issue.

FWIW, this seems very much like a graphics issue and not an IO-bound issue.

Edited October 3, 2017 by listrophy
clarification of suspicion of problem

[DrLicor]

"Game development engine producers Unity has strongly recommended to its users to avoid the upgrade to macOS 10.13 for the moment, as despite the firm fixing a number of issues that plagued developers using the tool with High Sierra's beta releases, there are still some faults that need to be rectified to make the game engine stable on Apple's latest operating system -- and APFS is inducing problems in other game titles as well."

source: https://www.google.nl/amp/appleinsider.com/articles/17/09/29/apfs-in-high-sierra-causing-problems-for-unity-engine-cities-skylines-civilization-v-more/amp/

read the whole article for more info on the problem. 

[Samssonart]

Neither forcing OpenGL or running KSP from an HFS+ partition seems to work for everyone, but it does in some cases. We are now in communication with Unity to see if there's anything that can be done about this problem, but it seems the release of High Sierra is breaking compatibility with many things, gaming and non-gaming related. We'll make an announcement when we have an answer from Unity, even if just an official "stay away from High Sierra for now", I'll keep you posted.

[Wyzard]

I can understand APFS causing the problems with assets not appearing in the Unity editor, since that actually relates to loading files.  But the in-game stuttering and oscillating back and forth between the same two frames?  I'm baffled as to how a filesystem could cause that.  It's not like the game is loading files from disk every frame; it does all that at startup.

…And running KSP from an HFS+ disk doesn't help.  My money's still on it being WindowServer, not APFS.

Edited October 6, 2017 by Wyzard
Tried HFS+, no luck

[JPLRepo]

https://forum.kerbalspaceprogram.com/index.php?/topic/166190-macos-users-please-read/

[Kopmatt88]

1 hour ago, JPLRepo said:

 

YES!! Thank you! This, from @Wyzard's post in that thread, works: "However, -force-opengl (which tells Unity to use its legacy OpenGL backend) seems to resolve the problem — no stuttering, even when running the game from an APFS partition.  I've tested with the Steam version of KSP 1.3.0, on a 2016 13" MacBook Pro with Touch Bar and Iris GPU."

 

I can confirm it works in 1.3.1 too. I can finally get back to KSP again! 

[listrophy]

Got it working!

This did not work: -force-glcore

This did work: -force-opengl

The filesystem didn't matter; I was able to run without stuttering from an APFS partition.