30x Slower LSP Initialization with .NET10 & Unity?

[Majavaa]

I recently updated my NIXOS configuration and noticed that the 0.22 and 0.23 versions were making my work Unity sessions in neovim go from 5-10 second init time to like 4 minutes.

I pinned csharp-ls to the 0.20 version that is in nixpkgs/25.11, and that worked perfectly. It sounds like the issue might be related to some regressions that were found in .NET10...

I don't expect a fix in this repo, just curious on if this is something that is known here. I can't provide detailed logs because of NDA but looking at nvims lsp.log, all the errors/warnings are the same on both versions, but there is an extremely and painfully obvious hang on 0.21+

[razzmatazz]

I suspect it is Roslyn 5.0/5.3 that came with 0.21. Do you think it is possible for me to generate/retrieve Unity solution/project that has similar parameters? Is there an open-source project that I could try?

[razzmatazz]

Also, do you see a busy CPU during those 4 minutes?

[Majavaa]

I suspect it is Roslyn 5.0/5.3 that came with 0.21. Do you think it is possible for me to generate/retrieve Unity solution/project that has similar parameters? Is there an open-source project that I could try?

There is this page https://github.com/JackyChenGit/awesome-unity-games?tab=readme-ov-file

I will try out the BoatAttack from the official UnityTeam and see if I can replicate at least some time loading difference. But these are on older editor versions and there could be a common denominator with my company's project

Also, do you see a busy CPU during those 4 minutes?

No it's quite as expected, maybe a tad bit lower than a normal startup. I notice that towards the end, a few seconds before the highlighting kicks in and it finishes initializing, a dotnet process appears for 5 seconds. I think normally that appears much much sooner

[Majavaa]

https://github.com/unity-technologies/megacity-metro

I ended up trying this project as the other ones didn't work in the editor due to old versions, but I could not get the LSP to start, likely due to the ECS codebase, those tend to only really work in rider and vs.

I am not sure what projects would be the same. I do know that on an internal Unity package that I develop, the project is basically a fresh unity project with a handful of scripts. The LSP will load in like 2 seconds max, where on the 0.21+, it takes like 10seconds or more.

So any Unity project with a handful of scripts (ideally Unity 6), should already be able to demonstrate the load time difference

[makcimbx]

I can confirm that in large Unity projects it is almost impossible to wait for initialization.