Comment 37 for bug 600178

Revision history for this message
dack (dack) wrote :

Things I've tried:

- Run under classic or unity - Very bad tearing. Unredirect fullscreen has no effect unless decorators are killed, in which case it behaves the same as classic (no effects).
- Run under classic (no effects) - One tear instead of multiple tears. The vertical position of the tear changes, sometimes it moves off the screen for a while but then comes back later.
- Disable C1E in bios - C1E is known to cause timing issues (messes with HPET somehow). When C1E is enabled, the tearing is definitely worse. As I'm not concerned about the power saving, I left C1E off.
- Disable other bios power management features - no effect.
- Use "mplayer -rtc" - Similar effect to disabling C1E.
- Different players - totem, vlc, mplayer, etc. All behave the same.
- Proprietary driver vs nouveau - no difference. tried all vsync/vblank settings.
- mplayer -vo gl2 (with proprietary driver) - tearing changes slightly, but is still present.
- lowlatency kernel (https://launchpad.net/~abogani/+archive/ppa) - no difference.

My conclusions:
- Tearing effects both nouveau and proprietary drivers, all players, and both opengl and xv
- None of the workarounds so far have solved it completely
- Disabling C1E makes a significant improvement
- Unredirect fullscreen doesn't work unless decorators are killed
- classic (no effects) is also effected, although not as bad

At this point my best guess is that it is either a kernel or xorg bug.