vc-git slows Emacs down quite a bit, trying to find a way to remove hooks

[Wei Liu <liuw@liuw.name>]

Hi all

I find that vc-git takes quite a lot of time to load, both in Emacs 23
and Emacs snapshot. On my dev machine it takes up to 21 seconds. :-(

I don't want to disable vc-mode entirely, I just want to make sure
that vc-git doesn' t get loaded when I don't need it.

There was a topic [0] on this issue on stackoverflow. I took the
advice to remove vc-find-file-hook from fine-file-hook list, thus
speeding up Emacs a lot. But when I save file, vc-git gets loaded once
again, which consumes 21 seconds. So my questions are a) how to
disable this save file hook (I grepped in vc-*.el, didn't find
save-*-hook), b) are there any other hooks I need to take care of?

Extra questions (to developers and/or Emacs gurus): Why is vc-git so
slow (see [0] for profiling details)? Is there a genuine way to fix
this?

My setup: Intel Q9450, 4GB Ram, 500GB 7200rpm disk. Was playing with
Linux kernel git repository, which was stored in local disk.



Thanks
Wei.

[0] http://stackoverflow.com/questions/6724471/git-slows-down-emacs-to-death-how-to-fix-this