Public bug reported: [Problem Description] On a hybrid graphics laptop (Intel iGPU + NVIDIA dGPU) running Ubuntu 24.04 in "On-Demand" mode, the gnome-shell process consistently holds an active context on the discrete NVIDIA GPU, even when the system is completely idle.
This prevents the dGPU from entering its D3cold power state (0W). As a result, the dGPU idles at ~1-5W and ~40°C, causing significant unnecessary power drain and reducing battery life on Wayland. This behavior can be observed with tools like `nvtop`, where `/usr/bin/gnome-shell` is always listed as a process on the NVIDIA GPU (Device 0). [Steps to Reproduce] 1. Boot the system into a GNOME on Wayland session in Hybrid Graphics (On-Demand) mode. 2. Close all applications. 3. Let the system idle for a minute. 4. Run `nvtop`. 5. Observe that `/usr/bin/gnome-shell` is listed as a process on the NVIDIA GPU (Device 0) and that the GPU is consuming power. [System Information] - Ubuntu Release: 24.04.3 LTS - gnome-shell package version: 46.0-0ubuntu6~24.04.9 - Hardware: Lenovo LOQ 15IAX9 (Intel i5-12450HX + NVIDIA RTX 4060 Mobile) --- lsb_release -rd --- Description: Ubuntu 24.04.3 LTS Release: 24.04 --- apt-cache policy gnome-shell --- gnome-shell: Installed: 46.0-0ubuntu6~24.04.9 Candidate: 46.0-0ubuntu6~24.04.9 Version table: *** 46.0-0ubuntu6~24.04.9 100 100 /var/lib/dpkg/status 46.0-0ubuntu6~24.04.3 500 500 http://security.ubuntu.com/ubuntu noble-security/main amd64 Packages [What you expected to happen] When idle and no applications are using the dGPU, gnome-shell should release its context on the NVIDIA card, allowing it to power down to 0W to conserve battery. [What happened instead] gnome-shell remains active on the NVIDIA GPU, keeping it in a low-power but awake state, consuming 1-5W continuously. [Evidence] A screenshot from `nvtop` clearly demonstrating the issue is attached. ** Affects: gnome-shell (Ubuntu) Importance: Undecided Status: New ** Tags: battery gnome-shell hybrid-graphics nvidia optimus power-drain wayland ** Description changed: [Problem Description] On a hybrid graphics laptop (Intel iGPU + NVIDIA dGPU) running Ubuntu 24.04 in "On-Demand" mode, the gnome-shell process consistently holds an active context on the discrete NVIDIA GPU, even when the system is completely idle. This prevents the dGPU from entering its D3cold power state (0W). As a result, the dGPU idles at ~1-5W and ~40°C, causing significant unnecessary power drain and reducing battery life on Wayland. This behavior can be observed with tools like `nvtop`, where `/usr/bin/gnome-shell` is always listed as a process on the NVIDIA GPU (Device 0). [Steps to Reproduce] 1. Boot the system into a GNOME on Wayland session in Hybrid Graphics (On-Demand) mode. 2. Close all applications. 3. Let the system idle for a minute. 4. Run `nvtop`. 5. Observe that `/usr/bin/gnome-shell` is listed as a process on the NVIDIA GPU (Device 0) and that the GPU is consuming power. [System Information] - Ubuntu Release: 24.04.3 LTS - gnome-shell package version: 46.0-0ubuntu6~24.04.9 - - Hardware: Lenovo LOQ 15IAX9 (Intel i5-12455HX + NVIDIA RTX 4060 Mobile) + - Hardware: Lenovo LOQ 15IAX9 (Intel i5-12450HX + NVIDIA RTX 4060 Mobile) --- lsb_release -rd --- Description: Ubuntu 24.04.3 LTS Release: 24.04 --- apt-cache policy gnome-shell --- gnome-shell: - Installed: 46.0-0ubuntu6~24.04.9 - Candidate: 46.0-0ubuntu6~24.04.9 - Version table: - *** 46.0-0ubuntu6~24.04.9 100 - 100 /var/lib/dpkg/status - 46.0-0ubuntu6~24.04.3 500 - 500 http://security.ubuntu.com/ubuntu noble-security/main amd64 Packages + Installed: 46.0-0ubuntu6~24.04.9 + Candidate: 46.0-0ubuntu6~24.04.9 + Version table: + *** 46.0-0ubuntu6~24.04.9 100 + 100 /var/lib/dpkg/status + 46.0-0ubuntu6~24.04.3 500 + 500 http://security.ubuntu.com/ubuntu noble-security/main amd64 Packages [What you expected to happen] When idle and no applications are using the dGPU, gnome-shell should release its context on the NVIDIA card, allowing it to power down to 0W to conserve battery. [What happened instead] gnome-shell remains active on the NVIDIA GPU, keeping it in a low-power but awake state, consuming 1-5W continuously. [Evidence] A screenshot from `nvtop` clearly demonstrating the issue is attached. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2130332 Title: gnome-shell holds wake-lock on NVIDIA dGPU in Optimus mode, preventing power-down To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/2130332/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
