2021.1 playmode FPS so low that testing heavier scenes becomes undoable

We have a project in 2020.1 and have been studying the possibility to upgrade from Unity 2020.1.2f1 to Unity 2021.1.0b3. However, after upgrading, we've seen a huge FPS drop when running our project in the editor. In busier scenes, the in-editor playmode can get down to 20FPS, making testing new features extremely complicated.

As we cannot share project-specific screenshots and sources, we replicated the problem by creating a new project on both Unity 2021.1 and 2020.1, using the standard URP template. No changes were made to either project or URP settings.

In 2020.1, the average FPS stays around 420FPS:


In 2021.1, the average FPS stays around 79FPS.



We know in-editor performance is expected to be worse, and building the project would give us faster FPS, but this is not a sustainable development workflow. **It is not clear if this is something that is being worked on and we should expect improvements on future versions, or if this is the new baseline that we should expect for Unity after 2021.1.0b3.**

When looking at the profiler, it seems that EditorLoop and RenderLoop are significantly longer in 2021.1, and the RenderLoop structure is different (which is expected, given the new features we're getting).

2020.1 profiler overview and zoomed RenderLoop section:



2021.1 profiler overview and zoomed RenderLoop section:



Any comments on that would be greatly appreciated, as it would help us make a better, more informed decision regarding whether or not we should update to 2021. We're really looking forward to make use of the new features, so it would be great to have input on this.

A full downloadable version of the project and screenshots in this thread can also be found here:
https://github.com/diogoriba/unity-editor-fps-drop-on-2021.1

Thank you!

 

Just a small fyi, I have just installed 2021.1.22f1 to test, the FPS in general displayed in the current project I'm working on (shown by both the stats Graphics counter and a custom UI text element placed on it) is higher, around 250fps when on 2021.1.14f1 was around 140fps.

CPU profiler also says a per-frame (both editor and player loops) of less than 4ms plus the usual hiccups.

However, what's displayed on the screen is nowhere resemblant of a 250fps experience, it's plagued by glitches and hiccups that don't seem to appear anywhere on the profilers. It feels more like 22.4948 fps non round rate with random hiccups. Close to unusable to be honest.

Note:
I'm on macOS which seems to have an ever growing degrading experience with every release (on this version I can left click and if I move the mouse to quick after the click it will detect the click somewhere else where the mouse was after for example). So since you are on Windows, your mileage might vary.

Update:
In case this thread is still being monitored, I went two versions below, 2021.1.20f1 and the frame rate is considerably smoother, doesn't show as high as in .22f1 but it's steady and without hiccups. Maybe this is something to take a look, will be issuing a bug report.

 

I have the same issue on 2021.1.23f1. I'm getting an FPS of around 9 in the editor of a brand new 2D project that has a single square sprite added to it.

Device info:
Mem: 128Gb
CPU: Intel I9 - 14 core
GPU: NVidia RTX2080

To reproduce, create a new 2D project, add a square sprite and then add a basic movement script to the sprite.

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class TestController : MonoBehaviour
6. {
7.     private float speed = 5f;
8.     private Vector2 velocity;
9.  
10.     // Update is called once per frame
11.     private void Update()
12.     {
13.           float moveInput = Input.GetAxisRaw("Horizontal");
14.         if (moveInput != 0)
15.         {
16.             velocity.x = Mathf.MoveTowards(velocity.x, speed * moveInput, Time.deltaTime);
17.         }
18.         transform.Translate(velocity * Time.deltaTime);
19.      
20.     }
21. }

Run the scene and press A or D. The FPS drops to very low numbers.

For comparison, on this same PC in Unity 2019 I was able to run a 3D AI simulation containing over 500 animated dinosaurs all performing path finding and evasion and still get more than 30 FPS in the editor.

 

Update: This issue only seems to occur if a GameObject is selected and that object has values in the properties window that are being update (for instance, transform data).
If I select an object whose values are not changing the issue doesn't occur, so it appears to be caused by editor UI updates when the game is running.

I'm now using 2021.2.4f1 and haven't noticed the issue.

 

Bump, I have exactly the same problem. Went from a stable 60~80 FPS on the latest 2020 down to hardly 55 FPS after updating the project to 2021.2.17f1.

 

@LeonhardP anyone investigated this?

 

Hey @Neiist, I have gone ahead and went farther down the line, I'm currently o 2021.2.19f1 (just before the LTS that just came out) and it's good enough. A lot better in my experience.

Both macOS 12.3.1 and Unity 2021.2.x have brought quite the QoL smoother experience.

Editor UI actions are still weird though, I can leave things in a drag n drop state (i.e. reparenting an object) and if I don't move the mouse at least one pixel it seems that it doesn't refresh the UI events and it never finishes it. Moving it too much might end up in another game object and parent's it to that one.

 

Same Here! In 2019 it was running smooth, I updated to 2021.3.7f1 and the project is slow, both on mobile and desktop.

 

Hello, I have been using 2020.3.23f1 for a year, but since I have moved to M1 Mac, I updated my version to 2021.2.6f1 but my whole team members who are using Intel Mac's experiencing huge FPS drops (even 15-20 fps on default SampleScene) and not sure how to fix it.