I updated from 331.38 (which I have been using for months without problems) to the 334.16 Beta yesterday on Arch Linux (3.12.9 Kernel) and immediately started seeing problems. When I opened nvidia-settings to confirm the new version the right side of the window started to flicker between the “X Server Information” and “X Display Configuration” window when moving the mouse over the menu on the left. Later I noticed the same problem in Chromium, when hovering over certain UI elements an image I was viewing started to flicker really fast.
However this doesn’t happen always but very often. First I wanted record it with the built-in Screen-Recording of Gnome 3, but the flickering always stopped when recording the video. I recorded a few videos with my smartphone illustrating the problem. Xorg server version is 1.15.0.
Image switcher in the top right corner makes image flicker. No flickering when mousing over the black space left and right of the image.
Same scenario using the Chromium tabs to cause the flicker when moving the mouse
nvidia-settings OpenGL bitmap flickers even when not moving the mouse, disappears permanently when moving the mouse. Also notice the dropdown fields getting highlighted when moving the mouse around.
nvidia-settings. Buttons flicker when moving the mouse.
EDIT: Downgraded to 331.38 and the issue is fixed so it’s definitely a regression with the 334.16 driver.
This looks like a problem caused by the system compositor not properly waiting for X rendering to finish before performing OpenGL rendering in response. The GL_EXT_x11_sync_object extension was designed to solve this problem, but it looks like cogl (the back-end library used by GNOME’s compositor) doesn’t use it yet.
That does not seem to be the case (yes that problem exists but this is a different story). This particular bug is simply a bug on how we handled the buffer_age extension in clutter. I have fixed in upstream clutter. The patch is also in the 1.16 branch (not just 1.18) so should end up in distros soon.