Another Attempt At Reducing GNOME's Mutter Input Latency

Prolific GNOME contributor Daniel Van Vugt of Canonical working to optimize the desktop stack for Ubuntu continues his great upstream-focused work on enhancing the performance of various key components. This past week he posted a new merge request that seeks to lower the input latency further for the Mutter compositor / window manager.

Mutter MR #661 is Van Vugt's latest input latency reduction work for Mutter. This is designed as a replacement to his nearly one-year-old unmerged patches for delivering input events sooner when possible but ended up having technical limitations.

This new implementation processes input events out of phase with server redraws and should lead to one frame lower input latency than the status quo. The input event frequency remains matched with that of the display's refresh rate.

The merge request was just opened three days ago on this new Mutter input latency reduction attempt and those wanting to learn more details on the technical side of it can do so via Gitlab. Hopefully we'll see this code merged in time for September's GNOME 3.34 release.