Where is information of "git read-tree" stored?

Hello,

following situation:

- Project hosted on GIT. Have a local copy and push to remote server.
- Small addon is hosted on a remote SVN server
- I now cloned the SVN to a local GIT (svn git clone)
- Then I used the instructions from here:

<http://git-mirror.googlecode.com/git-history/7444c60/howto/using-merge-subtree.html>

to get the local SVN copy merged into a subdirectory on my project GIT. Anything
worked well.

To test the worst case, I cloned my project GIT to a new local repository. The
remote connection to the local SVN copy was lost, so I recreated it.

Now, for some reason, I can immediately call

git pull -s subtree Bproject master

to pull changes from the SVN copy to the subdir... I didn't have to call "git
read-tree" again. Where is this information stored? Why does GIT know where the
remote repository data has to be placed to? Can I view this information? Can I
edit it?

Is there some information available somewhere on which data is pushed to server
and which is only in my local repo?

What will happen if my SVN checkout to local GIT repo gets lost? Can I just
clone this from SVN again, connect this to my project GIT and it will work just
well without problems? Or should I keep a copy of this GIT repo on server just
to be sure nothing bad happens?

Thanks in advance

Yours

Manuel