This has to be one of the strangest situations I’ve run into. It seems that having a mouse plugged into my PC (or not) is impacting my FPS in games. Has anyone ever seen anything like this?
For reference I’m on a VFIO GPU passthrough VM with an unRAID host and Windows 11 guest. I don’t even have to pass the mouse through to the VM. Just having it plugged into USB and connected to the host impacts it.
I first noticed this when trying to run Red Dead Redemption in Xenia emulator but now I’m seeing it in other games too. I noticed my FPS in games had suddenly dropped lately, but I normally play everything remotely via Moonlight and Sunshine. I went to play directly on my PC today and discovered my gaming mouse has kicked the bucket sometime in the last couple of days. I plugged in a new mouse WHILE RDR was running in Xenia and watched the FPS go from 30 ish FPS to 60 (the cap). Unplugged it and the FPS dropped back down. Plugged it back in and FPS shot back up to 60. How the heck???
Now I cant reproduce the problem anymore! And my old gaming mouse is working again for some reason. I had unplugged and re-plugged it several times with no success before I gave it up as a lost cause but now suddenly its working again.
For context, it was still plugged in when the strange framerate issues were happening. I got to wondering if whatever failed on it was causing the issues somehow so I went to try plugging it back in (I unplugged it after figuring out that plugging in a new mouse seemed to fix the problem) and it works fine. and unplugging all mice and re-plugging them seems to have no impact on FPS.
I even rebooted the VM several times during the time when the strange behavior was happening and it made no difference. But now everything seems to be back to normal.
Perhaps my old gaming mouse is on its last legs and was malfunctioning and causing problems, then started working again and they went away? Maybe it was shorting or partially shorting the USB port?
I have no clue. I’m at a loss but I’m glad it seems to be working again now.
Well, it used to be a wireless mouse but the battery is long shot and I lost the receiver sometime after that so it’s wired only now.
The new one I am using now is also wired only. I decided to just give up on the old one as it is VERY old and probably going bad, and use the new one. So far no other problems with it. Fingers crossed.
in a vm yes…
i had a mouse affect fps.
it was a multi poll rate 0-1000ms …
when attached to usb 3.0 (at the time) the fps would fall and rise with the pole rate of the mouse.
the solution was just swap the mouse to a usb 2 header and tell the vm to pole the usb at 2.0 or 1.1 speeds.
i found 1.1 worked best for me.
Another option is energy saving vs timers. On a VM where there’s lots of hardware not present, perhaps there’s nothing to wake up the CPU to run timer callbacks. Plugging in a mouse, would be enough to have some kind of timer setup.
To be clear, this would be a bug, but I routinely see this failure mode in soft-realtime large scale distributed systems.
These are some good suggestions. It’s hard to prove which one is right now though unfortunately because the issue seems to have gone away and I haven’t been able to reproduce it for several days now. I will be sure to come back and update if I learn anything new though, or if it starts happening again so I can try to narrow down the cause.