Trivial actions are not appearing immediately

This depends on how fast is your hardware, but doing these things necessarily take a little time...

Or would you suggest to preload things (eg the icons in menus) to speed things up (but in that case, opening the session will probably get slower) ?

Yes, I strongly suggest some kind of caching or preolading, because I find this behaviour very annoying: it looks like something is "locking". I can sacrifice the start time if it gives me smooth feeling in normal work.

Thanks for your bug. There is some others bugs about menu being slow upstream

This problem is made a LOT worse when using a Live CD. In fact, the first time the menu is opened, it can cause the CD to spin up again, with a long delay. If these icons were loaded into memory on startup of gnome-panel (during which the user is waiting around for gnome to start anyway), the delay would not be present.

Is this a more general problem than just gnome-panel? Does this apply to all icons in GTK menus? Perhaps GTK should preload all the icons whenever the application is started?

I have only noticed this annoying behavior in gnome main menu. In other gnome apps everything seems fine.

I'm sure something can be done about this. I've just done an strace on the menu opening, it tries to do ~1500 file opens (most of which are for non-existent files).

First of all, most of those should be preloaded (actually, they should be cached once, then the cache should be preloaded in one step). The argument that it takes up memory doesn't hold, because the memory is still taken up the first time I open the menu.

Second of all, any refresh can be done incrementally. There's no reason to flush the entire menu and re-open 1500 files, when one or two might be new. And especially you don't need to do it on every boot.

Third, even a refresh could be done in parallel, with a "nice -n 10" to make sure things don't get unpleasant.

Last, I don't even get it why it has to read the entire menu. If I'm going for the package manager I have no reason to wait for th 1500 file accesses, when it fact I'm only going to see about 20 icons on the way.

Upstream request on http://bugzilla.gnome.org/show_bug.cgi?id=445946