Re: svn to git, N-squared?

["Jon Smirl" <jonsmirl@gmail.com>]

On 6/11/06, Linus Torvalds <torvalds@osdl.org> wrote:
>
>
> On Sun, 11 Jun 2006, Jon Smirl wrote:
> >
> > I have Mozilla CVS in a SVN repository. I've been using git-svnimport
> > to import it. This time I am letting it run to completion; but the
> > import has been running for four days now and it is only up to 2004.
> > The import task is stable at 570MB and it is using about 50% of my
> > CPU. It is constantly spawning off git write-tree, read-tree,
> > hash-object, update-index. It is not doing excessive disk activity.
>
> This sounds like _exactly_ what happens if you don't repack occasionally.
> Expecially if you are using a filesystem without hashed filename lookup,
> but it's true to some degree even with that - the filesystem tends to end
> up spending tons of time in kernel space, trying to find a place to put
> new objects.
>
> I don't think git-svnimport has the repack logic in it, so that would be
> it.
>
> You can probably stop it with ^Z, do a "git repack -a -d", and then let it
> continue.

I have it stopped and I am running the repack.
There are 1.27M files in my .git directory

I ordered 2GB more RAM which should be here Tuesday.

> (The only reason for stopping it is actually to let "git repack" remove
> most of the object directories - many filesystems, including ext3, don't
> even speed up all that much if the directories are emptied after they've
> grown big, and it's much better if the object directories get totally
> removed and re-created)
>
>                         Linus
>


-- 
Jon Smirl
jonsmirl@gmail.com