Re: Multiple issues with wallpaper handling

["Jasper St. Pierre" <jstpierre mecheye net>]

Does the issue exist if you run raw mutter? I can't reproduce the
issue here with mutter or with gnome-shell. There's no performance dip
if I lock the screen or change the wallpaper.

The code that handles the wallpaper is here:

    http://git.gnome.org/browse/mutter/tree/src/compositor/meta-background-actor.c

You can see that it tries very hard to make sure that it's not holding
onto the pixmap any more than it needs to.

On Thu, Dec 1, 2011 at 8:58 PM, Chris Dekter <cdekter gmail com> wrote:
> Hi list,
>
> I am experiencing a very frustrating performance gremlin on my workstation
> with a dual-monitor setup. I have been trying for weeks to nail down the
> source of the problems, and have finally figured out that it is a
> combination of issues centering on wallpaper handling. Firstly my system:
>
> Ubuntu 11.10 x86_64 with Gnome 3.2.1
> Various kernel versions tested in the 3.0 and 3.1 series (all show the same
> symptoms)
> Radeon HD 5750 with 1GB RAM running the open drivers
> Two 24" monitors at 1920x1200@60hz
> (base system is Core i7 with 8GB of RAM)
>
> When I initially load shell, everything is smooth as butter. However, when I
> perform any of the following tasks, the overview animation slows to a crawl
> (although all other animations are still fine):
> - Lock the screen using Ctrl+Alt+L and then unlock
> - Change the wallpaper (image, svg or colour, doesn't matter)
>
> If I disable Nautilus from displaying the desktop (using gnome-tweak-tool),
> matters improves somewhat, but there is still a drastic drop in overview
> performance as soon as the wallpaper is changed. If I restart shell using
> Alt+F2 and r, performance becomes normal again. Also if I disable and then
> re-enable the second monitor, performance is recovered.
>
> I believe that this is a bug in the wallpaper handling in Gnome Shell. My
> theory is that an excessive number of copies of giant wallpaper pixmaps are
> being loaded into graphics memory. I also believe that possibly under some
> conditions the wallpaper pixmap is being loaded into memory not at the
> individual monitor's resolution, but at the X screen's resolution (in my
> case 3840 x 1020). I also think that possibly wallpaper pixmaps are not
> being removed from memory when a new wallpaper is set. Combine these issues,
> and you get a set of pixmaps that will choke even a 1GB graphics card.
>
> Thanks,
> Chris Dekter
> _______________________________________________
> gnome-shell-list mailing list
> gnome-shell-list gnome org
> http://mail.gnome.org/mailman/listinfo/gnome-shell-list



-- 
  Jasper