I can confirm this issue.
Intel i7 4700MQ, 8GB RAM, Intel HD4600, Mesa 18.3.1, Linux Mint 19.1 (with Ubuntu Bionic as the package base). Does not happen with Proton 3.7 either.
Same here.
Intel i7-8550U, 16GB RAM, Intel UHD 620 graphics, Mesa 18.2.8, KDE neon User Edition 5.15 (based on Ubuntu 18.04). Also doesn't happen with Proton 3.7.
Still happens with Proton 4.2-2.
@zebzorb Are you using the xserver-xorg-video-intel driver? I wonder if removing it would help. (and the opposite, if you are using it)
@hch12907 I was using xserver-xorg-video-intel-native-modesetting so I tried switching to xserver-xorg-video-intel, but after a reboot just to be sure, the mouse framerate thing still happened in Proton 4.2. I switched back since there seemed to be no change.
Did you manage to get around it? I guess I can wait until the next Ubuntu LTS release next year since Proton 3.7 works fine, but I'm curious if you fixed it on your machine.
I did not manage to fix the issue on my Mint, though recently I found that Proton 4.2 was working perfectly fine with Arch Linux, despite both OS running on the same hardware. The issue is with Ubuntu, but I am not exactly sure which part of Ubuntu caused it.
@hch12907 Ah, thanks for letting me know. I guess I can live with using Proton 3.7 for now, haha.
proton 3.7x4 2019-04proton 4.2x2 2019-04proton 4.2-2x1 2019-04proton 3.7-8x1 2018-11
In trying the beta release of 3.16-4 on Ubuntu 18.04.1 with the Intel modesetting driver active under Xorg, I've noticed that every game tested will run fine until it detects mouse input. Once mouse input is established, the framerate dips down to the single digits until mouse input ceases.
This issue does not occur with the same setup using the standard Proton 3.7-8. This issue also does not occur on other distros that I've tested with 3.16-4 and the modesetting driver, which include Ubuntu 18.10, Fedora 28 and Fedora 29.
This issue does not occur under Wayland either, for whatever that's worth.
My testing machine specs are as follows:
Intel i5 2520m CPU
6gb RAM
Intel HD 3000 graphics