BUG: VR.WaitForGPU forcibly occupies CPU when running in background

I'm working on a enterprise-level Unity3D project on OpenVR recently. Generally speaking it works great, yet when I send it into background (when other VR programs are running) Unity forcibly cooled FPS down to ~10. I've noticed that VR.WaitForGPU used ~100ms even if there are nothing being rendered. No active cameras.

I know there are no needs for rendering to HMD when you are in background, but what if I need it to be in companion window while I cannot even toggle off VRSettings.enabled? (which definitely caused crash)

In this situation, I have no way to improve framerate for now. Application.targetFrameRate did nothing. I need only the camera working for Main Display at this time, without removing the VR support altogether (which is needed earlier or later during life cycle)..

Looking forward to your kind help, Unity Team

 

Actually I'm finding a way to dynamically enable and disable VR support (which now caused CRASH)..

Or please give me a way to set frame rate manually other than 10fps / 100ms..

 

Anyone knows?

 

Here's how to enable/disable VR support:

UnityEngine.VR.VRSettings.enabled = false;

 

Thank you for your reply first. I've thought that no one may come to this thread yet

If there is no camera rendering to OpenVR, it's not necessary for Unity to be blocked by OpenVR driver and VR.WaitForGPU. And I do believe that this way will be more simple since toggling VRSettings.enabled is basically unstable. Also, I've downloaded 5.5 beta 10 today to see if VRSettings.enabled works or not (along with openvr plugin)

 

Which shall cause a crash under all 5.4 versions after OpenVR initialized first.

 

Yes, under 5.5b10 VRSettings.enabled works. But there are something remained that will cause a crash. I'm trying to reproduce that.

 

It is simple to reproduce. Create a scene with OpenVR(SteamVR) Plugin. Enable VR by default; when the scene is running with SteamVR working, disable it and crashed immediately.

 

Submitted a bug report mentioned this thread.. Case 847878

 

So do you mean my crash reported yesterday (with 5.5p10) is caused by SteamVR plugin? Or is that fixed in some versions (like 5.4.2p4)?

Without SteamVR plugin it is really hard to get information like, controllers. Maybe I should connect to OpenVR Native Plugin directly? I need to get controller info when in background (without actual rendering).

 

How about the question these days?

I think I should split my program into two parts: one for rendering to screen and one for rendering to headset... Otherwise Steam still crashes with VRSettings.enabled switching from script.