Playing the game attached to Case 1108597 in 2019.3.0a3 editor feels very slow and unresponsive compared to earlier Unity versions. Looking at the Profiler shows a 43ms cost on “EditorLoop” pretty much all the time.
What can I do to get rid of this cost and make it playable in the editor again? “Deep Profile” unfortunately does not reveal any information on that EditorLoop entry.
I did not have any object selected where an expensive inspector window was shown. Only the game view, hierarchy, project window and console was visible.
“Profile Editor” revealed the performance degradation is caused by the Hierarchy window. When I close the Hierarchy window, performance is significantly better. I believe still slower than in earlier versions, but much better.
I’ve submitted a bug-report and also attached the saved profiler data of both cases, with and without having the Hierarchy window open.
I’ve just upgraded my project from Unity 2018.4.1f1 to Unity 2019.1.5f1 – apart from the editor being slower than the previous versions (again), I’m also seeing a significant performance issue when the Hierarchy window is open. It actually makes the editor near unusable when I’m editing multiple scenes!
Only work around right now, is to have the hierarchy window open, but not visible… then only switch to it when you want to do something specific (which is often), grind your teeth trying to complete said task and then hide the hierarchy window again after.
Please fix this urgently and back-port for the fix to Unity 2019.1.5f1 as well. I cannot believe a bug like this made it into a major release.
I was able to reproduce it in an isolated project and submitted the bug-report:
(Case 1161198) 2019.3: Hierarchy window gets slower with more GameObjects
Looking at the description on the issue, seems there could be more to it than this based on my experiences. However, hopefully the issues relate, so fixing the root cause will fix all.
I can see where it’s happening… but not the details beyond that. My development workflow has been suffering from this for months now. Any idea when this will be fixed?
Another weird side-effect / symptom – when in play mode the same editor hierarchy view performance is much better. When stopping play the issue comes back again the same.
Update here: I tracked my problem to an asset, it looks like one of the editor upgrades changed something with the assets DLL. Whatever it was caused the performance issue. I deleted and reinstalled the asset and now the Hierarchy is performing much better.
