Official Improving iteration time on C# script changes

Yes, you're right. I was using the term "assemblies" interchangeably, but at various points I was referring to precompiled dll assemblies, and at others was referring to asmdefs. That is confusing, and I admit I was confused because I was assuming that asmdefs automatically reference other asmdefs that are marked as auto reference, which was incorrect. I'm sorry for the confusion. I've gone back and added edits to my original post for clarification.

If that is not the situation you've faced, that's fair. I was just trying to brainstorm suggestions for where some extra recompile times could be coming from.

 

Finally this bug got moved to „wont fix“

https://issuetracker.unity3d.com/is...-script-in-editor-became-really-slow-in-trunk

its over boys. Close the thread

 

I can confirm the same behavior in 2022.2.12. While it isn't a permanent fix, clearing \library does decrease editor iteration time if the cache is old. Unfortunately, this is one possible solution among the many required to improve iteration time. Ultimately, Unity has to remain focused on improving iteration time.

 

I believe this is the issue you are looking for: Unity Issue Tracker - Increased Script Assembly reload time (unity3d.com) It is a catch-all for editor iteration performance work. If you review prior posts in this thread, you'll learn more about Unity's plans for addressing the issue.

 

Have you read the resolution note there?

"
RESOLUTION NOTE:

I have filed several issues separately to fix particular parts of this that were slow. We have a Prism dashboard now to help monitor iteration times on a broader scale. The team are working on CoreCLR where we hope to make a big improvement to this issue, but we're unlikely to work on fixing this specific bug report."

 

Everyone has, and we're all familiar with this pattern, too:

1. Problem too hard, promise a big new shiny thing in much time...

2. ...delivery half arsed thing with more problems and promise to fix until it too problematic - goto 1

 

In this case I would rather say the bug report is too generic.
Unity has "improved" performance in many areas, however, these performance improvements have been offset by new features. Without these improvements, it would be even worse now.
I think Unity with Mono has reached the limit of what is possible. In my opinion, CoreCLR will have a massive performance boost (once the editor runs on coreCLR and .NET 8)

 

Not to sound rude, but it's hard to take your opinion of it seriously when you don't even know how to spell it. But it appears we're still years away from CoreCLR. Even just a few months ago they said they're far away. At the rate Unity moves I'd think 2025.1 would be very optimistic.

 

I am the master of twisted letters!

I think CoreCLR will come with unity 2024.x for player build, editor as you say 2025.x. Unless the plans have changed and it's coming at the same time.
As far as I remember, at first only CoreCLR will come, but the profile stays with .Net Standard 2.1, and only later .NET 8 when both player and editor are running on CoreCLR.

I think it is now difficult to justify wasting enormous resources on optimizing things that are of little use in the end and are again obsolete with CoreCLR

 

I came for a solution, all i found is just depressing

 

Well, I am somewhat relieved. I thought i had been wasting 5 seconds an iteration for years without knowing it could have been faster.

But it isn't and hasn't. (Has it? Im on 2022.1.16f)

Whew.

I guess it will be what it will be until it isn't.

In the meantime, I think it's time I rebuild my library folder. Its been six months or so...


EDIT:. After deleting rebuilding my library folder, it went from 10Gb to 6, and script compilation went from about 7 seconds to about 4.

 

https://unity.com/releases/editor/alpha/2023.2.0a22

 

Can someone please try this and let me know if the compilation time is reduced when using fewer and more files?

 

I don't know how many individuals experiencing this issue fall in the same group as me but what I found causing the vast majority of my slow compilation and reload times was a poorly designed custom editor script (10-15 seconds to over 2 minutes during a 24-hr period). I had the script attached to multiple prefab objects as I was refactoring and testing functionality. After looking through Editor.log and seeing issues in the asset importer window pointing to this editor script it gave me an idea on where to focus my efforts. After refactoring the custom editor code and removing redundant testing prefabs holding references to the underlying editor class my reload times have dropped below 10 seconds.

I just wanted to let people know the issue is sometimes self-created or possibly from poorly designed 3rd party assets imported into your project. Reading through this topic might make some people believe it is 100% Unity's issue and there is nothing they can do about it. I thought that, but thankfully I took the effort to figure out it was my fault.

 

This affects completely new, empty projects without any 3rd party assets, which is why people correctly believe it's 100% unity's issue. The slow reload script assemblies issue is affecting many, but not all people, so the community is split into those who are unaffected and those who find development intolerable due to it.

So many people are reporting this issue in forums all over, many of them veteran developers who have years of experience with unity: this is a genuine problem with the engine today and not due to user incompetence. In the past few years I have personally experienced it and seen my peers struggle with it, so it is disappointing that Unity continues to be unable or unwilling to address this.

I have been a longtime proponent of Unity in the past, but I have since switched to other engines, as have many other developers I know. Unity is simply no longer usable and there has not been any action on this for years.

 

They said 'sometimes' and not 'always'.

Sometimes slow domain reloads are the result of some issue on the side of the user. It might be poorly written editor code, it might be their hardware is not up to snuff, it might be their project is running off a HDD (yes this has happened).

But not always.

Hence why it's important to profile the editor and see where the most time is spent during a domain reload. As someone who makes a lot of my own editor tools I do profile them to make sure I'm now bogging down my other projects that depend on them, and there have been multiple times where I needed to fix a performance issue.

 

I am a day late, but I just came here to wish happy birthday to my comment,
one year down, only two more to go, see you in 2025!

 

Hi,
Is anyone aware of any good tutorials on what users can do to improve domain reload times?
I came across this article by John Austin, which is great, but I am looking for more / more detail.

(For context, I currently have near instant script compiling but 15 to 40 second domain reloads. I've been looking at the Editor Iteration Profiler but I'm finding it a bit overwhelming. I've got Reload Domain on enter play mode turned off. I've looked at Hot Reload, which looks cool, but its not really the solution I'm looking for. And for what its worth, I'm making use of assembly definitions and running Unity on relatively competent hardware: intel i7-13700K, M.2 NVMe drives, 64gb ram.)

 

Sebastian Schöner, who worked for Unity until just recently, posted this big blog post about this theme, it might be worth reading!

 

The article was very helpful. Thank you!

 

i need to admit, i didnt really cared about this problem anymore. i was stuck on an old project anyway that was using unity 2019 and there the compile times has been fine all the time. I started a new project today and evaluated a few versions and i must say. i am impressed with the latest LTS version of unity 2022!

unity 2019LTS: Script compilation time:1.772s
unity 2020LTS: Script compilation time:1.867s
unity 2021: Script compilation time:3.235s
unity 2022 LTS: 1.765sec

these are the compile times for an empty project without any package.
so. good job unity!

 

Have you tried script compilation HDRP ?

 

2.5-2.8 seconds

but i also (need to) have 11 packages now