GNOME's Wayland Session Shows Potential For Better Battery Life Than With X.Org

While not talked about as much as raw performance and other factors, but in the recent testing of the Lenovo ThinkPad T14s Gen2 laptop with AMD Ryzen 7 PRO 5850U, it was observed that the GNOME Wayland session by default on Ubuntu 21.10 is delivering better battery life / lower power consumption than using the GNOME X.Org session.

For those curious about Wayland vs. X.Org for mobile computing, the GNOME Wayland session is reliably having around up to a ~3 Watt power saving on battery with Radeon graphics at least compared to the traditional X.Org session with all of that crusty code running.

Here are some of the initial benchmarks while a larger, multi-system comparison is currently in the works...

The Wayland vs. X.Org GNOME session raw performance for various graphical/desktop applications on Ubuntu 21.10 aren't too different with the Wayland session being quite mature at this stage:






In a few gaming tests there was some advantages to the Wayland session for the Vega graphics performance:







But most interesting was seeing the battery power consumption results over the span of all the tests conducted over the span of about two hours each run:

On average the GNOME Wayland session for this AMD Ryzen powered Lenovo ThinkPad laptop had a 21 Watt average while switching to the classic X.Org session saw a 24 Watt average.

Monitoring the CPU package power consumption via RAPL as well confirmed around a 3 Watt savings on average when using the GNOME Wayland session.

Besides meaning a longer battery life, it also meant some thermal benefits too.

It was fun to see these savings with Wayland materialize at least under the GNOME session. Besides a larger multi-device comparison, a multi-desktop comparison could come soon if there is enough premium reader interest. This is an area of Wayland performance I haven't looked at much before but great to see a meaningful difference.