Re: Efficient cloning from svn (with multiple branches/tags subdirs)

From: Avery Pennarun <apenwarr@gmail.com>
Date: Oct 14, 2009, 18:26 UTC
Message-ID: <32541b130910141126u4df7f439i3d2926c2e1db9497@mail.gmail.com>
In-Reply-To: <20091014180013.GA24741@dcvr.yhbt.net>

On Wed, Oct 14, 2009 at 2:00 PM, Eric Wong <normalperson@yhbt.net> wrote:

Show 20 quoted lines

> Avery Pennarun <apenwarr@gmail.com> wrote:
>> I've been thinking about this myself for some time.  One option that
>> might be "interesting" would be to just grab the *entire* svn tree
>> (from the root), and then use git-subtree[1] to slice and dice it into
>> branches using your local copy of git (which is fast and uses no
>> bandwidth) instead of during the svn fetch (which is slow and uses
>> lots of bandwidth).  I think it would also simplify the git-svn code
>> quite a lot, at least for fetching, since there would always be a
>> global view of the tree and SVN things like "copy branch A to tag B"
>> would just be exactly that.
>
> This was actually the original use case of git svn back when I started.
>
>  git svn clone SVNREPO_ROOT   (without --stdlayout)
>
> It's still an option if you have the disk space for the working copies,
> but I had to create the branches/tags support since the working copies
> would be become prohibitively large.  If git-subtree could be
> taught to work on a bare repo (git svn has a --no-checkout option)
> it might be an option, too.

I've never tested git-subtree without a working tree, however, it doesn't *use* the working tree for anything when splitting, so at worst, there might be a minor bug or two. Thus, there ought never be a need to check out the whole huge tree (which I agree would be both slow and huge).

dcommit might be a little weirder. Though I guess if we fixed the git-svn-id tags in the split branches, you could just commit directly into a branch, then fetch the new commit back from the root, then rebase the branch, as dcommit already does.

You know, maybe this is actually easier than I thought... I was thinking committing back to svn would be complicated since it requires a working tree, but if we let you commit straight from one of the branches, it shouldn't actually be too bad at all. Hmm.

Have fun,

Avery