Nautilus starts up slowly. Why?

And a bonus question: how could I make it fast again?

If you press ALT+F2 and run:

nautilus --no-desktop

Is it ok?

actionparsnip requested for more information:
> If you press ALT+F2 and run:
>
> nautilus --no-desktop
>
> Is it ok?
I did a clean boot, started system monitor (Nautilus shown there as
running!), and did what you asked me above. It shows up as slow as usual.

However, I just realized that (at least in a given period) only the
first start of Nautilus is such slow. A second start is probably cached
or such?

@Gergely Máté
I agree with you; A more recent Nautilus is slower than Nautilus on previous Ubuntu, even by default.

I am using Ubuntu 8.04 and 10.04 on two separate computers.
I can't compare them directly, as both computers have different specifications.

But even on same system specification, there are two differences:

[1] Different filesystem by default (Ext4 on Ubuntu 10.04 and Btrfs on 10.10 or newer)
On Ubuntu 10.04 with Ext4, it is reported Software Center or Synaptic Package manager launches noticebly slower. As for Nautilus, personally I experience faster only for file copying.

[2] Added features included in more recent Nautilus
On Ubuntu 10.04, Nautilus 2.30 has dual-pane, tabbed navigation, longer file menu and context menu and Ubuntu One intergration by default. These added features perhaps may have affected Nautilus response and speed.

As for quick solutions, I only know some: turning off some of default features such as disable preview files option; disable auto mount media under Nautilus' Edit > Preferences; and uninstall Ubuntu One to remove background services [try this at your own risk].

Above all, there is no way to disable other features in Nautilus yet.

Try:

sudo add-apt-repository ppa:am-monkeyd/nautilus-elementary-ppa; sudo apt-get update; sudo apt-get -y upgrade

May help