Very poor VR preview and editor performance

[Commander_Scotty]

Hello! I’ve been experiencing a problem with a VR project lately. When I launch a level in the VR preview I experience very poor performance, characterized by extremely low frame rate, and frequent spikes in my GPU and CPU usage. Then after I close the VR preview, the UE editor continues to experience a low frame rate when a 3D view port is displayed.

Sometimes the VR preview performance stabilizes after a few seconds of poor performance and allows me to test my level as normal, but it takes several cycles of launching the preview and seeing if it stabilizes, then closing the preview if it doesn’t.

The problem became persistent when I upgraded to Unreal 5.3. I did experience the same problem briefly while using Unreal 5.2, but it ceased after a minor update was applied. The problem does not occur while playing other games in my steam library.

I’ve been looking for a solution for a while, and nothing I’ve found has resolved the issue. Here’s what my performance plots look like when the issue is occurring and when the preview is running stably.

Here are some details about my rig:
CPU: AMD Ryzen 7 2700X
GPU: Nvidia Geforce RTX 2060
RAM: 32 GB
VR: Valve Index, SteamVR 2.4.3
Unreal Engine 5.3.2 VR template

I’d appreciate any help I can get in figuring out what’s going on. It’s brought my dev flow to an absolute halt. Thanks!

[Rectus_SA (Rectus)]

It might possibly have the same cause as the issue in this thread, where the OpenXR rendering calls get desynced, which breaks the SteamVR runtime:

Vr headset tracking lag with packaged version only

hi, I will start by saying that I am new to Unreal Engine I usually use Unity but for this project, we decided to switch to Unreal. We are building a very simple VR game that we will need to use in an experiment, when we play in the editor everything looks fine. The tracking is perfect no delay etc but in the packaged version we have a problem with the tracking of the headset. It basically feels delayed. Every time you move your head there is a sling effect. There is no stuttering or frame loss…

If that is the cause, you would either have to use 5.4, or manually recompile the engine and patch in the fix.

Vr headset tracking lag with packaged version only

This issue has been fixed on UE5/Main here: https://github.com/EpicGames/UnrealEngine/commit/899a4c0874f2af141c5b42ea48d282c11a471ba7 The fix should go into the 5.3.2 hotfix.