Bug Unity 2021.3.11f1 URP *MAJOR* issues (Visual glitches, poor performance, etc.)

Hi,

We used Unity 2019.4.xx before, everything was pretty much perfect, our game performs very smoothly on most mobile devices and emulators. That's until we tried to deploy our game to play store and found out that, in short, we have no choice but to upgrade to either Unity 2020 / 2021. We did, we choose 2021, and the migration went rather smoothly, but soon found some major issues I couldn't find the solution of:

1. Build size increase
The build result (APK) size has increased quite considerably (~15 - 20 MB). We tried both IL2CPP modes (smaller & faster mode), both results in larger size than the ones we built with Unity 2019. I also notice selecting "faster runtime" mode causes some of our scripts to behave strangely, that's a bit difficult to explain, we use the "smaller" mode for now.



2. Visual glitches (Particle System)
This one only occurs in emulators. We tried Bluestack, Nox, & LD player, all have the same issue. It's related to particle system.

- You can see below the snowflakes are supposed to be small, but it randomly shows one big snowflake, just for one frame.


- It also happens to all other particle system objects, randomly, which I can't figure out when exactly those happen. Here's one more example, the left one is supposed to be a lens flare, the right one is supposed to be a smoke/dust trail (animated sprite sheet particle). Also occurred for a single frame.


Again, it only occurs on emulators, everything's normal on mobile device, except for the following issue:

3. Very poor performance
I notice our game now runs extremely slow on both emulator & mobile devices. Previously, it runs at 60 FPS, consistently. But now, with the same devices, the FPS sometimes drop to 30 and even 15 at times. Is there something we must do to our shaders / materials (which were made with the shader editor from 2019)? Is there some new hidden feature we can turn off to improve the performance?

Here's some more details regarding our project/editor:

Unity version: 2021.3.11f1
Render pipeline: URP 12.1.7
Target android level: 30 & 31 both tested
Min android level: 22

Please let me know if you need any more information. Thank you kindly for any help!

 

I am having the same problem. Did you find a solution?

 

Sorry but no exact solution so far, but I solved those with workarounds:

Problem 1: No solution here. Some people say it's because the incremental build works differently, which means different APK size is to be expected. I think we just have to live with this one.

Problem 2: I have found the root of cause, solution, and opened a new thread here.

Problem 3: No solution here neither. Our game still performs worse in overall. But I manage to help the performance by being more aggressive with optimizations, causing the game to look a tad bit uglier but well, what can we do? So far I think the slow down is because the batching system works differently in 2021, people say it's less aggressive but "more correct".

It's unfortunate no officials came to help to address these issues and we had to sacrifice valuable development time to dabble around, it took tons of trials and errors lol. Fun times

 

Thank you for a detailed description.
I'm experiencing problem 1, 2.
Unfortunately that solution didn't work for me.
Unchecking multithreaded rendering seems to make it less frequent, but it still happens.

I'll keep trying different things, and if I find a solution, I'll share it in the thread you linked.

 

Have the same problem 2 with particles on Android devices after upgrading from Unity 2020.3.25 to 2020.3.40 and built-in rendering pipeline (also tested 2020.3.35-2020.3.40 and 2021.3.10 versions and have save glitches). It only happens with OpenGL ES api on Android and never with Vulkan api, disabling multithreaded rendering does not help. Looks like it depends on overall scene complexity because with small test scene with a few Particle systems glitches never happen. Also glitches happen with new project without any custom scripts or shaders.

 

Can you file the bug report?

 

Upgrade to Unity 2022.1.23f1 it should fix it and any related Gles issues

 

Build size increase ,one is issue like Build size increase when updating to IAP 4.2+: project dependency changed; and other is engine code changed.

 

Apk crash on start fix!
Delete all android resolved library
It will work
But I highly recommend you should delete the libraries little by little till you have a playable apk
The crash is as a result of duplicate aar and plugins which Unity ignores on build