Bug#696323: metacity: Alt-tab is so slow it is unusable with compositing

[Stéphane Démurget]

Package: metacity
Version: 1:2.34.3-3
Severity: important
Tags: upstream patch

Dear Maintainer,

   * What led up to the situation?
I'm using the window switcher (alt-tab) with metacity compositing activated.

   * What exactly did you do (or not do) that was effective (or
     ineffective)?
Just use alt-tab.

   * What was the outcome of this action?
Opening the alt-tab dialog (even for a quick-switch, which means a quick alt-
tab just to switch application without the dialog showing) for 30 windows of
dimension 1600x900 takes 3.6 seconds, and this is a fairly recent computer
(<2y). For 6 windows it is already a full second, which gets on one nerves by
making it barely usable, and the time increases linearly depending on the
windows x dimension.

   * What outcome did you expect instead?
The alt-tab dialog should open quickly: this is maybe the most used feature of
a window manager/desktop.



-- System Information:
Debian Release: wheezy/sid
  APT prefers testing-updates
  APT policy: (500, 'testing-updates'), (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 3.2.0-4-amd64 (SMP w/4 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           3.4.0-2
ii  gsettings-desktop-schemas  3.4.2-3
ii  libatk1.0-0                2.4.0-2
ii  libc6                      2.13-37
ii  libcairo2                  1.12.2-2
ii  libcanberra-gtk0           0.28-6
ii  libcanberra0               0.28-6
ii  libgdk-pixbuf2.0-0         2.26.1-1
ii  libglib2.0-0               2.33.12+really2.32.4-3
ii  libgtk2.0-0                2.24.10-2
ii  libgtop2-7                 2.28.4-3
ii  libice6                    2:1.0.8-2
ii  libmetacity-private0a      1:2.34.3-3
ii  libpango1.0-0              1.30.0-1
ii  libsm6                     2:1.2.1-2
ii  libstartup-notification0   0.12-1
ii  libx11-6                   2:1.5.0-1
ii  libxcomposite1             1:0.4.3-2
ii  libxcursor1                1:1.1.13-1
ii  libxdamage1                1:1.1.3-2
ii  libxext6                   2:1.3.1-2
ii  libxfixes3                 1:5.0-4
ii  libxinerama1               2:1.1.2-1
ii  libxrandr2                 2:1.3.2-2
ii  libxrender1                1:0.9.7-1
ii  metacity-common            1:2.34.3-3
ii  zenity                     3.4.0-2

Versions of packages metacity recommends:
ii  gnome-session [x-session-manager]           3.4.2.1-3
ii  gnome-session-fallback [x-session-manager]  3.4.2.1-3
ii  gnome-themes-standard                       3.4.2-2

Versions of packages metacity suggests:
ii  gnome-control-center  1:3.4.2+git20121016.29d7c0-1
ii  xdg-user-dirs         0.14-1

-- no debconf information