To initialize the GTK+ framework (among other frameworks), one must allocate a given amount of memory on the heap. Depending on what parts of the stack (dbus, libgnomeui, etc) one loads, this ranges from 1-3 MB. While it's important to work to fix this (eg, by mmaping things), there's only so much we can do.
I believe it would be beneficial to have a host process for daemons like this. The system would need to be set up in such a way so that mini-daemons could be put into a different process via configuration (eg, for debugging).
One of the types daemons on the desktop is panel applets. We have a process to display the clock, the volume switcher, etc. The panel already has a framework for doing these in process. What would be the benefit of using this? To find out, I put two applets in process: the wnck-applet which handles the workspace switcher and task list and the notification-area-applet, which handles the notification tray.
I actually already had the patch for this. openSUSE already uses a similar patch thanks to Federico. I decided to modify the patch so that it would not put clock-applet in process. Some people have complained that because this links to evo, it might be at risk for crashing. Fine, whatever. Let's start with some low hanging fruit.
Here are the results for private dirty rss, before and after the patch.
|gnome-panel||4008 kb||4248 kb|
|TOTAL||8432 kb||4248 kb|
This is over 4mb! Just for putting two things in process. There are three other applets on my Dapper computer that could benefit just as easily: trash-applet (trivial), mixer applet (see below), clock applet (links to evo stuff. maybe?). I hope other distros follow the led of openSUSE in this area.
One thing to look at: the mixer applet loads every single part of gstreamer. This causes extra memory usage (gstreamer plugins badly need constification), as well as extra spinning of the disk. Can this be fixed?