Bug#648626: GNOME 3's Metacity makes OpenGL applications unstable

[Émeric Maschino]

Package: metacity
Version: 2.34.1-2
Severity: important

Hello,

With the delivery of GNOME 3 into Testing, Metacity was upgraded from
version 2.30.1-3 to version 2.34.1-2.

Since then, I'm experiencing stability issue when running
"OpenGL-intensive" applications (e.g. ioQuake3-based applications or
WebGL Conformance Test Suite
https://cvs.khronos.org/svn/repos/registry/trunk/public/webgl/sdk/tests/webgl-conformance-tests.html):
application runs fine for 10-20 sec. and then seems to lock up.

Switching to a text console shows multiple instances of error messages like:

[drm:radeon_ib_schedule] *ERROR* radeon: couldn't schedule IB(11)
[drm:radeon_cs_ioctl] *ERROR* Failed to schedule IB!

Stopping and restarting X didn't help: the display is then garbaged,
and switching back again to the text console reports the same error
messages.

This is with current Metacity 2.34.1-2 when running GNOME 3 in
fallback mode (I can't try GnomeShell at this time because of an udev
issue).

I'm pretty sure this has to deal with some Metacity processing now
performed by the GPU, whereas 2.30.1-3 was relying upon CPU. Indeed, I
had no problem with Metacity 2.30.1-3 that was previously in Testing.
However, I was experiencing the same kind of problem when switching
the window manager from Metacity to Mutter in the GNOME 2 era, and
IIRC, Mutter was heavily relying upon the GPU.

-- System Information:
Debian Release: wheezy/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: ia64

Kernel: Linux 2.6.38-2-mckinley (SMP w/2 CPU cores)
Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages metacity depends on:
ii  gnome-icon-theme          3.2.1.2-1
ii  libatk1.0-0               2.2.0-2
ii  libc6.1                   2.13-21
ii  libcairo2                 1.10.2-6.1
ii  libcanberra-gtk0          0.28-3
ii  libcanberra0              0.28-3
ii  libgconf2-4               2.32.4-1
ii  libgdk-pixbuf2.0-0        2.24.0-1
ii  libglib2.0-0              2.28.8-1
ii  libgnome2-common          2.32.1-2
ii  libgtk2.0-0               2.24.7-1
ii  libgtop2-7                2.28.4-1
ii  libice6                   2:1.0.7-2
ii  libmetacity-private0a     1:2.34.1-2
ii  libpango1.0-0             1.29.4-2
ii  libsm6                    2:1.2.0-2
ii  libstartup-notification0  0.12-1
ii  libunwind7                0.99-0.3
ii  libx11-6                  2:1.4.4-2
ii  libxcomposite1            1:0.4.3-2
ii  libxcursor1               1:1.1.12-1
ii  libxdamage1               1:1.1.3-2
ii  libxext6                  2:1.3.0-3
ii  libxfixes3                1:5.0-4
ii  libxinerama1              2:1.1.1-3
ii  libxrandr2                2:1.3.2-2
ii  libxrender1               1:0.9.6-2
ii  metacity-common           1:2.34.1-2
ii  zenity                    3.2.0-1

Versions of packages metacity recommends:
ii  gnome-session-fallback [x-session-manager]  3.0.2-3

Versions of packages metacity suggests:
ii  gnome-control-center  1:3.0.2-3
ii  gnome-themes          2.30.2-1
ii  xdg-user-dirs         0.14-1

-- no debconf information