While just missing out on the recent Mutter 50 beta release, merged today to Mutter Git ahead of next month’s GNOME 50 desktop release are some improvements to the Variable Refresh Rate (VRR) support.
As covered last week, GNOME 50 is promoting VRR to no longer be an experimental feature. Rather than being hidden by default, Variable Refresh Rate support will appear on capable systems out-of-the-box within GNOME Settings for those wanting to activate it. VRR support allows dynamically adjusting the display’s refresh rate to match the output frame rate to help reduce/eliminate screen tearing, less stuttering, lower lag, and all-around a smoother gaming experience.
Following its recent promotion, Mutter now has some enhancements to its VRR code thanks to well known engineer Michel Dänzer of Red Hat. A set of 11 patches switch over the VRR code path to using the deadline timer and make other improvements to the code. This code also gets the Wayland commit timing protocol to work properly with VRR enabled.
The patch switching over VRR to using the deadline timer explains of its benefit:
“Similar approach as in the clutter frame clock:
Attempt to set the deadline for the earliest possible start of the next refresh cycle, based on deadline evasion. If it’s already too late for that, start ASAP.
This also ensures the presentation doesn’t happen before the target time.
It also picks up the latest mouse cursor position at the deadline, which can result in lower input -> output latency.”
More details on these late improvements for VRR in GNOME 50 via this merge. GNOME 50.0 stable is due for release on 18 March and will be found in the likes of Ubuntu 26.04 LTS and Fedora Workstation 44, among other Linux distributions.
