Profiler issues 2019.3.3 vsync spikes?

Hi,
Those spikes come from the ProfilerWindow repainting (at a lower frame rate, so that there are frames in-between that are less impacted by the Editor running on the same main thread as the game in playmode).
Please note that Profiling Playmode is not ideal to figure out your game's performance and profiling a built player gives way more relevant and cleaner data.

As to the 60fps cap: In 2019.3 the Game View's Aspect ratio drop-down menu contains a VSync (Game view only) toggle, so that's probably on and why you're seeing a difference between 19.1 and 19.3

 

Also, If you ever want to get more info about what took time in the EditorLoop, you can switch the target from Playmode to Editor (or turn on Editor Profiling in versions Pre-2019.3).

 

Are you setting Application.targetFrameRate?
What platform did you build for?

As for the Semaphore, these samples are explained in the CPU Profiler Manual. The short of it is, your main thread is waiting for the Rendering thread to finish presenting the frame, which might be down to VSync but you'd need to check Timeline view to see that.

 

yeah, unless you have some heavy GPU work to do, those 29ms for present make no sense. If that was down to VSync, it could've ended after 16ms.

What Graphics backend are you using? Have you tried GPU profiling that (potentially with a GPU hardware vendor's Profiler)?

 

Also, other applications on your Machine might impact the GPU timings so maybe you'd want to profile the game running on a different machine than your Unity Editor, or close the Unity Editor and gather some profiler data via the Profiler.enableBinaryLog API, then load that data in afterwards.

 

If you're profiling in the Editor, that's likely the Profiler Window. Others in the Editor is mostly taken up by Editor stuff. For more details you'd have to switch from Playmode to Editor, but if you want to see more accurate timings for your game, you should profile a build.

 

Doesn't look like the Profiler Window repainting and it's happening under the GarbageCollector category so it's not the same issue but related to Garbage Collection, i.e. the Editor UI, here the SceneView, happened to request a new allocation for managed memory when there was not enough of that left, so Garbage was collected.

To address that, you should check out what all was allocating managed memory (GC.Alloc Samples) look at the worst offenders and see if you can reduce those. Check out the Call Stacks profiling option for help on that search.

Some of that might come from the normal running of Unity's editor, some might come from plugins, or your own assets and some might come from your game. Addressing allocations in your game code can help final performance of your game too, Editor only allocations will "only" trip up your editor occasionally but if that's a lot, it may be worth to examine those. If it comes from the base Editor code, there's not much you can do there besides reporting bugs on the places that allocate unreasonably much.

You may also want to check if switching to Incremental GC helps.