I have been for a couple of days now looking at improving the startup speed of GNOME, and this is what I’ve found so far (patches not included).
- gnome-session does a DNS check on the hostname, not sure why. I removed that and things seem to work as before.
- Some programs in gnome-session are being started with g_spawn_sync. I changed some of them to be g_spawn_async.
- esd is started twice, once in gnome-session and once in gnome-settings-daemon
- Screensaver and typing break are not essential services for the startup, so I’ve changed gnome-settings-daemon to start those 2 processes on idle callbacks, so that they are started when everything else is running
- xrdb is run 3 times in gnome-settings-daemon!
With these changes I’ve gone from starting the session in 12/15 seconds to 4/6 (I even got sometimes that ‘your session has lasted less than 10 seconds’ error after loging out immediately), and, I think, there is a lot of room for improvement still.
Not sending patches yet, since the changes I’ve made are quite ugly so far (commented out code, #ifdef’s, etc), but will be as soon as I get them sorted out.
Update: hadn’t really read Lorenzo’s analysis before, so I guess all the things he points out make much more room for improvement.
Also, bad news is that on the first login, things are quite slower (15/20 seconds), but I guess this could be easily improved by preloading libraries and programs.
Keep up the good work Rodrigo, those seem like some fairly easy tweaks for some big gains. Thanks!
Very cool work! Note, though, that Erwann already noticed the multiple xrdb calls in the d-d-l thread about possibly removing xrdb (see http://mail.gnome.org/archives/desktop-devel-list/2005-August/msg00300.html) and already filed a bug with a patch for this issue — http://bugzilla.gnome.org/show_bug.cgi?id=314774.
IIRC the reason for the first thing is that if your hostname doesn’t resolve Bonobo Activation causes massive delays. I think the check is there so the user is warned of this configuration error. I’d leave it ….
the dns check is just awful.
a couple of times installing a fresh ubuntu, I have wanted to begin my first desktop session whilst my networking config was only half finished.
I got some strange dns error and gnome-session wouldn’t log into the desktop… quite frustrating.