Excessive VRAM usage on Nvidia GPU

[Daniel15]

On my work laptop that uses an Nvidia GPU, Maliit is using 374 MB VRAM, even when it's just idle (i.e. I don't actually have the virtual keyboard open):

% sudo nvidia-smi                                  
Wed Jul 17 17:45:08 2024       
+-----------------------------------------------------------------------------------------+
| NVIDIA-SMI 555.58.02              Driver Version: 555.58.02      CUDA Version: 12.5     |
|-----------------------------------------+------------------------+----------------------+
| GPU  Name                 Persistence-M | Bus-Id          Disp.A | Volatile Uncorr. ECC |
| Fan  Temp   Perf          Pwr:Usage/Cap |           Memory-Usage | GPU-Util  Compute M. |
|                                         |                        |               MIG M. |
|=========================================+========================+======================|
|   0  NVIDIA GeForce RTX 3050 ...    Off |   00000000:01:00.0  On |                  N/A |
| N/A   66C    P3             12W /   35W |    2059MiB /   4096MiB |     17%      Default |
|                                         |                        |                  N/A |
+-----------------------------------------+------------------------+----------------------+
                                                                                         
+-----------------------------------------------------------------------------------------+
| Processes:                                                                              |
|  GPU   GI   CI        PID   Type   Process name                              GPU Memory |
|        ID   ID                                                               Usage      |
|=========================================================================================|
|    0   N/A  N/A    156666      G   /usr/bin/kwin_wayland                          95MiB |
|    0   N/A  N/A    156783      G   /usr/bin/maliit-keyboard                      370MiB |
|    0   N/A  N/A    156796      G   /usr/bin/Xwayland                              62MiB |
|    0   N/A  N/A    156839      G   /usr/bin/ksmserver                              1MiB |
|    0   N/A  N/A    156841      G   /usr/bin/kded6                                  1MiB |
|    0   N/A  N/A    156850      G   /usr/bin/plasmashell                          290MiB |
|    0   N/A  N/A    156896      G   /usr/libexec/kactivitymanagerd                  1MiB |
|    0   N/A  N/A    156942      G   ...6/polkit-kde-authentication-agent-1          1MiB |
|    0   N/A  N/A    156943      G   /usr/libexec/org_kde_powerdevil                 1MiB |
|    0   N/A  N/A    156947      G   /usr/libexec/xdg-desktop-portal-kde             1MiB |
|    0   N/A  N/A    157089      G   kdeconnectd                                     1MiB |
|    0   N/A  N/A    157202    C+G   /usr/bin/xwaylandvideobridge                   15MiB |
|    0   N/A  N/A    157238      G   /usr/bin/kaccess                                1MiB |
|    0   N/A  N/A    157240      G   /usr/libexec/DiscoverNotifier                   1MiB |
|    0   N/A  N/A    157611      G   /usr/lib64/firefox/firefox                    340MiB |
|    0   N/A  N/A    158047      G   /usr/bin/kwalletd6                              1MiB |
|    0   N/A  N/A    158139      G   ...bin/plasma-browser-integration-host          1MiB |
|    0   N/A  N/A    158567      G   /usr/libexec/baloorunner                        1MiB |
|    0   N/A  N/A    159072      G   ...ec_t%2C iptables_exec_t%2C iptables          1MiB |
|    0   N/A  N/A    159381      G   ...bin/plasma-browser-integration-host          1MiB |
|    0   N/A  N/A    159817      G   ...erProcess --variations-seed-version        288MiB |
|    0   N/A  N/A    161601      G   /usr/bin/konsole                                1MiB |
+-----------------------------------------------------------------------------------------+

This particular system only has 4GB VRAM, which means that Maliit is using nearly 10% of it. I'm not actually using Maliit, and disabling it in System Settings → Keyboard → Virtual Keyboard freed the VRAM.

This is an issue for GPUs with low VRAM because Nvidia's Linux drivers don't share system RAM, so hitting the VRAM limit often crashes the Xwayland process if not the entire desktop environment.

Environment:

• Lenovo X1 Extreme Gen 5
• Nvidia 3050Ti GPU with 4GB RAM
• Fedora 40
• Nvidia driver 555.58.02

[ninja-]

the issue is the same on AMD, I just disabled the onscreen keyboard as I don't actively use it