Enter Play Mode takes 20-30 seconds

I use Unity 2020.1 beta 11 on a reasonably decent Windows 10 machine. Unity & the Project loads faster than it takes to enter play mode.

I use Entities 0.11, Hybrid Renderer V2, Unity Physics
My scene has 2 (complex) gameobjects that get converted (between 850-900 entities total, some fairly simple meshes and colliders, and basically a few dozen objects from a nested prefab, with 3-4 children each.)

Entering Play Mode is excruciatingly slow - it usually takes around 30 seconds, sometimes 1-2 minutes. Sometimes it's fast, 5 seconds or less. It seems to SOMEWHAT be related to how my subscenes are loaded (current setup just has the GameObjects with a ConvertToEntity behaviour on them), and what my burst and livelink settings are.

This is close to an "empty" project, basically a few cameras, two spaceships, a skybox, and a planet.

If I remove the two objects that are to be converted, entering play mode is almost instantaneous.

Packages:

Spoiler: manifest.json

Code (JavaScript):

1. {
2.   "dependencies": {
3.     "com.unity.burst": "1.3.1",
4.     "com.unity.collab-proxy": "1.3.7",
5.     "com.unity.entities": "0.11.0-preview.7",
6.     "com.unity.ide.rider": "2.0.5",
7.     "com.unity.ide.visualstudio": "2.0.2",
8.     "com.unity.ide.vscode": "1.2.1",
9.     "com.unity.inputsystem": "1.0.0",
10.     "com.unity.jobs": "0.2.10-preview.11",
11.     "com.unity.nuget.newtonsoft-json": "2.0.0",
12.     "com.unity.physics": "0.3.2-preview",
13.     "com.unity.render-pipelines.universal": "9.0.0-preview.14",
14.     "com.unity.rendering.hybrid": "0.5.1-preview.18",
15.     "com.unity.scriptablebuildpipeline": "1.7.3",
16.     "com.unity.searcher": "4.3.1",
17.     "com.unity.test-framework": "1.1.14",
18.     "com.unity.test-framework.performance": "2.2.0-preview",
19.     "com.unity.textmeshpro": "3.0.0-preview.14",
20.     "com.unity.timeline": "1.3.3",
21.     "com.unity.ugui": "1.0.0",
22.     "nuget.mono-cecil": "0.1.6-preview",
23.     "com.unity.modules.ai": "1.0.0",
24.     "com.unity.modules.androidjni": "1.0.0",
25.     "com.unity.modules.animation": "1.0.0",
26.     "com.unity.modules.assetbundle": "1.0.0",
27.     "com.unity.modules.audio": "1.0.0",
28.     "com.unity.modules.cloth": "1.0.0",
29.     "com.unity.modules.director": "1.0.0",
30.     "com.unity.modules.imageconversion": "1.0.0",
31.     "com.unity.modules.imgui": "1.0.0",
32.     "com.unity.modules.jsonserialize": "1.0.0",
33.     "com.unity.modules.particlesystem": "1.0.0",
34.     "com.unity.modules.physics": "1.0.0",
35.     "com.unity.modules.physics2d": "1.0.0",
36.     "com.unity.modules.screencapture": "1.0.0",
37.     "com.unity.modules.terrain": "1.0.0",
38.     "com.unity.modules.terrainphysics": "1.0.0",
39.     "com.unity.modules.tilemap": "1.0.0",
40.     "com.unity.modules.ui": "1.0.0",
41.     "com.unity.modules.uielements": "1.0.0",
42.     "com.unity.modules.umbra": "1.0.0",
43.     "com.unity.modules.unityanalytics": "1.0.0",
44.     "com.unity.modules.unitywebrequest": "1.0.0",
45.     "com.unity.modules.unitywebrequestassetbundle": "1.0.0",
46.     "com.unity.modules.unitywebrequestaudio": "1.0.0",
47.     "com.unity.modules.unitywebrequesttexture": "1.0.0",
48.     "com.unity.modules.unitywebrequestwww": "1.0.0",
49.     "com.unity.modules.vehicles": "1.0.0",
50.     "com.unity.modules.video": "1.0.0",
51.     "com.unity.modules.vr": "1.0.0",
52.     "com.unity.modules.wind": "1.0.0",
53.     "com.unity.modules.xr": "1.0.0"
54.   }
55. }
56.  

I haven't been able to consistently improve this behaviour, and it is really slowing me down while prototyping. Any tips?

 

https://blogs.unity3d.com/2019/11/05/enter-play-mode-faster-in-unity-2019-3/

did you try to enable this?

 

This setting doesn't make a significant difference.

I think it's the dependency resolution of when systems execute, maybe. I wonder how that can be so slow, but it really seems to get worse the more UpdateAfter attributes I use.

(I have like a dozen fairly simple systems, really nothing fancy)

The game runs at over 160fps burst compiled once it's loaded.

 

Ok I think this thread belongs in the DOTS forum instead.

 

I narrowed it down, if I place my objects in a sub-scene, the load time is drastically decreased unless I have the subscene, meaning it is, indeed, entity conversion.

Entity conversion seems to choke on objects that:
- contain a nested hierarchy of nested prefabs
- have authoring components on multiple levels

Tomorrow, I'll try to pre-register each of the prefabs (there's 5, and about 5-15 instances of each) somehow before conversion, stop the conversion and run a manual instantiation of the prefab entity.

This really throws a spanner into my authoring workflow, but it might work out.

 

Try this https://forum.unity.com/threads/introducing-the-editor-iteration-profiler.908390/#post-5963222

 

So this is my Gameobject hierarchy, and each of these (and probably 1 more page down) has similarly nested objects, each with their own authoring components.

Doesn't it convert each prefab only once? Is these a shortcut way to do it, other than stopping conversion at one point and manually declaring/converting the nested prefabs?

 

Oddly enough, it was about to show how even with just 1 object, it's never below 3 seconds (1.8 of which were spent by the entity conversion system)... that ship alone used to take 10 seconds. I didn't meaningfully change its architecture that I know of, was just getting started with my rearchitecting.

But now, no matter how I do it, it all happens in <700 ms, which I feel is very acceptable.

I'll investigate what's going on here, and why it is now faster than ever, even with 3x the content in the scene, or the subscene, or both.

 

I did upgrade to Beta12 earlier today. hmm.

 

Interesting, thank you!

How do I save my entities "as prefabs", i.e. "as assets" without conversion while maintaining the comforts of nested prefabs?

They always seem to have to live in some kind of scene as some kind of gameobject.

I'd love to just load them by addressable name, authoring them exactly once, for instance.

(PS It's a real world prototype for a medium project)

 

One option is to create a 'prefab' scene where you store all your prefabs, settings, etc.

I'm sure there are other ideas floating around.

 

How do I prevent these from getting injected into my main world, though?

(Not sure what to search for, really... maybe something in the conversion system API?)

 

Ahhh I could run a prefab registry IConvertToEntity and have that just declare all the prefabs, not placing the objects.

 

Yeah, I'd create some type of 'prefab conversion' component that gives them the actual built in Prefab component, gives them an ID to store them in a map etc to setup however you generally handle your assets.

Then you can just instantiate directly from the existing Entity, very fast, no conversion required.