Lag spike in empty URP project in LTS 2021.3.16f1

Hello,

I just started Unity back after a good year and a half of not touching it.
I launched a new URP project on the LTS 2021.3.16f1.

After fidgeting a little bit with the new input system to learn to use it, I saw some lag spike in play mode.
Using the profiler I saw that once every 10 secondes to 1 minutes, a big lag spike going up to 33ms/frame appear.
But as the profiler is defiling too fast I couldn’t stop in time to analyse it (any way to make the profiler’s graph longer to analyse more in the past or something, I would really like to know what is causing this spike).

I decided to create a new, empty URP project on the same version, the lag spike was here again (just launching play mode, doing nothing, with empty project).

So I decided to try on the last 2022.2.2f1 version, new URP projectno lag spike.
Tryed with a classic project (not URP) on 2022.2.2f1no lag spike.
Tryed a classic project (not URP) on 2021.3.16f1no lag spike.

I couldn’t find any topic about a similar issue so I was wondering if I am the only one getting the problem (may come from my PC?) or is it maybe some URP setting on this version that cause this?
But as it is the last version of the last LTS, many people use it and would have reported this issue I guess.

Also, what is the drawback of not using a LTS version? From what I understand it is the support duration that is longer with the LTS (long term support)?

Have a good day !

i also get this problem in play mode, but not in an actual build, so i haven’t bothered worrying about it. i’m on LTS 2021.3.12f1 myself, haven’t updated.

should prolly submit a bug report for it…

I have heard people complain about this to. Make a bug report and attatch the repro projects so it can be fixed

Yes, after fidgeting around some more it seems indeed that the performances issues are just in editor and not in build.

I will submit a bug report as you suggested, thanks !

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Press the red circle button in the profiler’s toolbar. This toggles recording on and off. When you see the spike, stop recording. Now you can go to that frame and look at the details of what is causing the spike.

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