Dragging a selection in many programs turns Hyprland into a slide show

[Szwagi]

Hyprland version

v0.50.1 (and earlier)

Regression

No

Describe the bug

When GPU memory clocks are low, dragging the selection rectangle in Dolphin turns Hyprland into a slide show (500ms or more frametimes). This does not happen in Plasma (Wayland) under the same conditions, it manages smooth responsive 360Hz when dragging the selection rectangle. It also does not freeze Hyprland when running Dolphin with XWayland (but Dolphin input is "smoothed", not responsive).

Under normal conditions, this causes a ~300ms hiccup when beginning to drag the selection and fixes itself when the GPU boosts the memory clocks.

Reproduction steps

1. Open dolphin
2. Run sudo nvidia-smi --lock-memory-clocks=100,100
3. Drag the selection rectangle (it's a slide show)
4. Run sudo nvidia-smi --lock-memory-clocks=5000,5000
5. Drag the selection rectangle (it's smooth)

System info and config

Tested on Arch and NixOS
Tested on nvidia-dkms and nvidia-dkms-open.
7800X3D, RTX 4080
cfg.txt

[Szwagi]

I have found two more programs where this happens so it's not unique to Dolphin.

1. Resizing the canvas in KolourPaint
2. Dragging the selection in Flameshot (flameshot gui --clipboard --accept-on-select)

Hyprland 0.51.0 built from branch main at commit 8164b90bc2839d4d2a10c0d2b26c4a413ecf90b2  (config: fix crash when some configurations include non-integer values (12056)).
Date: Thu Oct 16 14:33:06 2025
Tag: v0.51.0-89-g8164b90bc, commits: 6507

Libraries:
Hyprgraphics: built against 0.2.0, system has 0.2.0
Hyprutils: built against 0.10.0, system has 0.10.0
Hyprcursor: built against 0.1.13, system has 0.1.13
Hyprlang: built against 0.6.3, system has 0.6.3
Aquamarine: built against 0.9.5, system has 0.9.5

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