Re: Truncating and cleaning a imported git repositary to make it more usable

["Alex Bennee" <kernel-hacker@bennee.com>]

On Fri, Mar 28, 2008 at 12:50 PM, Avery Pennarun <apenwarr@gmail.com> wrote:
> On 3/28/08, Alex Bennee <kernel-hacker@bennee.com> wrote:
>  >  I've succeeded in porting our whole CVS repository into git (with plenty
>  >  of swap, cvsps is very memory hungry). Now we have a reference
>  >  historical repository I need to think about creating one we actually use
>  >  for day to day use (the .git is currently in the order of 650Mb which is
>  >  a little heavy for pushing around DSL links willy nilly).
>
>  You used git-repack and git-gc, right?  If not, the repo will be
>  bigger than it should be.

Oh yes. Unfortunately for 7 years of development of an embedded
platform there is a lot of cruft in the CVS repo :-(.

However as it needs to be a drop in replacement for the current repo
we can't just drop all the history and start from a fresh repo.

>  >  1. Find the common ancestor point for all the product branches I want to
>  >  keep in the repo.

>  "git show-branch -a" probably does what you want.

Cool. Or in fact git-show-branch --merge-base seems to be the baby.

I'm sure it's been mentioned before but the plethora of git commands
can make it hard to find the commands you want even
if your sure there is some way of doing it :-)

>  >  2. Create a new repo, starting at the common ancestor point
>  >
>  >   2(a). I'd need to remove the orphaned old CVS modules which are still
>  >  around but not referenced any more.
>  >
>  >  3. Create the product branches and import ANCESTOR..BRANCH_HEAD into
>  >  them
>
>  You probably want to look at git-filter-branch, particularly the
>  --parent-filter option.
>
>  Note that 2(a) would be easiest if you just did it before importing
>  from CVS at all, since it's easy to remove old modules from CVS just
>  by moving the files out of the way.

Trouble is looking at the current repo I'm not sure which modules are
orphans (at the common anscestor point) and which have been added
since.

Of course now I can easily go back in time (easier than in CVS) I can
build up this list.

>  Have fun,

For certain values of fun ;-)

-- 
Alex, homepage: http://www.bennee.com/~alex/