I've got a problem with gnome-shell that I partially solved, but want to ask question of why it works that way and if you can help me with fixing it permanently.
I am using Ubuntu 12.10, with installed Gnome3 (using gnome-shell). When I login (even if I just unlogged from Gnome) to Gnome session, everything starts ok, but gnome-shell takes about 20% of CPU and its responses are very slow (searching for applications takes around 30 seconds and so on). It is very annoying. But, when I kill gnome-shell process, and than start it by "nohup gnome-shell &" from terminal, it starts again, but now without any troubles, fast, like it should.
Can you help me how to fix this permanently? (it's really annoying to kill and run gnome-shell after every session login, and also, it takes about 15-30 seconds to start again).
I googled this problem and found out that there might be a problem with gnome-shell extensions. But when I open tweak-tool I find that I have no gnome-shell extensions, so there is nothing I can disable.
Thanks for any help.