Xorg sessions have higher output lag than Wayland sessions.
Test case:
Grab a window with the mouse and drag it around smoothly.
Expected: the same minimal gap between the cursor and the window's title bar in both Xorg and Wayland sessions.
Observed: a bigger gap (higher latency) in Xorg sessions.
I only realized this was a bug when I stumbled on a fix while experimenting with the presentation timing logic in mutter, so assigning to myself.
ProblemType: Bug
DistroRelease: Ubuntu 18.10
Package: mutter 3.30.0-4
ProcVersionSignature: Ubuntu 4.18.0-8.9-generic 4.18.7
Uname: Linux 4.18.0-8-generic x86_64
ApportVersion: 2.20.10-0ubuntu11
Architecture: amd64
Date: Sun Oct 7 17:22:48 2018
InstallationDate: Installed on 2018-05-26 (133 days ago)
InstallationMedia: Ubuntu 18.10 "Cosmic Cuttlefish" - Alpha amd64 (20180525)
ProcEnviron:
TERM=xterm-256color
PATH=(custom, no user)
XDG_RUNTIME_DIR=<set>
LANG=en_AU.UTF-8
SHELL=/bin/bash
SourcePackage: mutter
UpgradeStatus: No upgrade log present (probably fresh install)
Xorg sessions have higher output lag than Wayland sessions.
Test case:
Grab a window with the mouse and drag it around smoothly.
Expected: the same minimal gap between the cursor and the window's title bar in both Xorg and Wayland sessions.
Observed: a bigger gap (higher latency) in Xorg sessions.
I only realized this was a bug when I stumbled on a fix while experimenting with the presentation timing logic in mutter, so assigning to myself.
ProblemType: Bug ature: Ubuntu 4.18.0-8.9-generic 4.18.7 256color DIR=<set>
DistroRelease: Ubuntu 18.10
Package: mutter 3.30.0-4
ProcVersionSign
Uname: Linux 4.18.0-8-generic x86_64
ApportVersion: 2.20.10-0ubuntu11
Architecture: amd64
Date: Sun Oct 7 17:22:48 2018
InstallationDate: Installed on 2018-05-26 (133 days ago)
InstallationMedia: Ubuntu 18.10 "Cosmic Cuttlefish" - Alpha amd64 (20180525)
ProcEnviron:
TERM=xterm-
PATH=(custom, no user)
XDG_RUNTIME_
LANG=en_AU.UTF-8
SHELL=/bin/bash
SourcePackage: mutter
UpgradeStatus: No upgrade log present (probably fresh install)