03-12-2018 09:08 AM - edited 03-12-2018 09:12 AM
I'm having a problem where the Vive playback has a slight but consistent jumpiness/stutter, seemlingly regardless of scene complexity. We have a fairly complex scene that shows jumpiness and reports missed frames, but when we remove almost all of the geometry to make the scene super simple the jumpiness and missed frames is reduced but does not completely go away. The Task Manager shows that both the CPU and GPU are running at below 35% capacity for the reduced scene, with 0% disk access.
This is all on a Razer Blade laptop with a nVidia GTX 1060 card (not a 1060M oddly). Also, the motherboard on this laptop has Intel HD 630 Integrated graphics, so it really has 2 GPUs. The Task Manager is reporting that both SteamVR and the app is running on the nVidia card, and I've even disabled the Intel GPU in the Device Manager (I didn't see any way to do it in the laptop's BIOS) and the results are the same.
The tracking seems solid and I've always done standing calibration before working with the app. The firmware is up-to-date on the HMD and Base Stations.
The jumping/stuttering is most noticeable when turning the head rapidly from side to side, but even when the HMD is not moving there is a periodic red blip for a missing frame in the Settings display. Also, when the app is running I get a red "Application" in Settings. When I display frame timing, I can see spikes above 11ms, but they seem to be mostly in idle, not any of the other colors. When I show details, I see spikes in "Wait for Present Spin", "Total GPU" (downward), "Compositor Render Sta", "Compositor Update En", "New Frame Ready", "New Poses Ready" and "Wait Get Poses Called" (the names get cut off), although it is hard to tell if one of those is causing spikes in the others.
I get basically the exact same behavior when running the Steam Tours app after our app has closed out. I even see a slight jumpiness when nothing is running (just the grey hemisphere) - then I don't see any read missing frame lines but I do see a red "Compositor " in Settings.
I have tried turning off WiFi, quitting any other application or system processes that are more than 0% on the Task Manager, and stopping a lot of services and nothing seems to help. The laptop is running Windows 10 Home 64-bit and the CPU is a 4-core/8-thread i7 at 2.8 GHz. It's running a hard disk which is probably at 5200 RPM I would guess.
At this point I'm stumped. The next step is to wipe the disk and re-install Windows fresh to see if that makes a difference.
Any ideas before that would be appreciated.
03-12-2018 10:43 AM
Update: I've set up a similarly configured desktop PC (GTX 1060) right next to the laptop. When I move the Vive cabling over to the desktop PC and sit in the exact same place I see almost no jitter/stutter. So it isn't any reflections in the environment or anything. It must be something in the laptop itself.
03-12-2018 12:14 PM
That being the case, a fresh Windows install might be just the ticket. Before we go that far though, is there anything installed on the old machine that might be using up clocktime/processor speed? You've got power settings maxed out and everything, right?
03-12-2018 01:26 PM
As far as I can tell, everything is maxed out. I killed a bunch of processes and services that looked like they might be stealing cycles but nothing seemed to matter.
03-12-2018 02:12 PM
Does SteamVR allow you to enable Asyncronous reprojection?
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03-12-2018 02:50 PM
Yes. "Allow asynchronous reprojection" and "Allow interleaved reprojection" are both on. I tried turning them off but it didn't seem to make any difference.
Update: we ended up restoring the factory Windows 10 installation on the laptop. Preliminary tests seemed to show that the jittet/stutter was greatly reduced. We are now doing a Windows Update, since the Windows version from the restore partition was ancient. This is taking forever but I will report when it is done.
03-12-2018 09:51 PM
I get slight stutter when turning with my headset as well, almost not there if I close Unity editor. Laptop Asus Strix nvidia 1050 ti. In the Nvidia settings, use set to performance, and use the Nvidia chip instead of the Intel HD. Looks like you already did that. I also use a M2 hard drive. So to get rid of the slight stutter, I don't think you will. And depending on certain games, it is even worse. Gorn for example uses real shadows and lags to heck now since they updated their game and filled it with a ton more meshes. There might be some other settings to boost the fps but I think it shifts from 60-90 while moving/turning. I can confirm moving the [CameraRig] provided by SteamVR for Unity creates major FPS issues.
03-15-2018 09:49 AM
So in your case, the stutter only occurs when you have Unity editor open as well?
03-15-2018 12:19 PM
Having Unity Editor open takes resources. The stutter is because the system is not running at 90fps constantly. If I use the desktop computer I have, it's perfect. The laptop just has a hard time staying at 90fps the entire time. Turning with the headset reduces the FPS. I have pretty good specs for my laptop, including M2 hard drive, it is just slightly less spec than a desktop. I am pretty sure that is what the other guy is experiencing too. Some games are far worse laggy. Gorn for example, lots of stutter but this game uses real time shadowing, no VR game should at this point. Turning down sample size can reduce the stutter. It is possible the stutter is because the video card is not necessarily as powerful or maybe because it has to go through the Intel HD port first, a lot of these laptops use Intel HD 4000+ as the HDMI port. It is not directly connected to the NVidia card, we use settings to make it work. This is why Oculus doesn't work at all, they haven't cared to make it work while the Vive does.