help moving boost.org to git

[Eric Niebler <eric@boostpro.com>]

I have a question about the best approach to take for refactoring a
large svn project into git. The project, boost.org, is a collection of
C++ libraries (>100) that are mostly independent. (There may be
cross-library dependencies, but we plan to handle that at a higher
level.) After the move to git, we'd like each library to be in its own
git repository. Boost can then be a stitching-together of these, using
submodules or something (opinions welcome). It's an old project with
lots of history that we don't want to lose. The naive approach of simply
forking into N repositories for the N libraries and deleting the
unwanted files in each is unworkable because we'll end up with all the
history duplicated everywhere ... >100 repositories, each larger than 100Mb.

So, what are the options? Can I somehow delete from each repository the
history that is irrelevant? Is these some feature of git I don't know
about that can solve this problem for us?

(Caveat: I'm new to git and still getting up to speed. An acceptable
answer is: go off an learn about feature X and come back to us.)

At boost, We've already discussed a few possible approaches. Feel free
to comment and/or criticize any of the solutions suggested here:

  http://github.com/ryppl/ryppl/issues#issue/4

-- 
Eric Niebler
BoostPro Computing
http://www.boostpro.com