# hg-to-git performance on big repos

2 messages from 2008-03-22 to 2008-03-22. Participants: Fedor V. Sergeev, Theodore Tso.
Thread: https://gitlist.dev/t/12808

## Fedor V. Sergeev, 2008-03-22 13:34

Subject: hg-to-git performance on big repos
Message-ID: <20080322162618.K47359@geo.geo.loc>
URL: https://gitlist.dev/e/20080322162618.K47359%40geo.geo.loc

```
Folks,

I'm trying to convert a relatively big Mercurial repo (70K commits) into Git using
contrib/hg-to-git.
It initially goes fine but starts to slow down nearly exponentially as the
number of converted changesets goes up.

git-fast-import seems to just hang around, while all the work (100% cpu)
is spent in that python thing. It does not eat up memory, pstack looks
fine, but after some 10K commits it just crawls.

It did not finish in 2 days and after that machine got a power down :(

Can anybody tell me is this normal or what?

thanks in advance,
  Fedor.
P.S. Yeah, if that does matter I'm doing it on OpenSolaris ;)

```

## Theodore Tso, 2008-03-22 14:27

Subject: Re: hg-to-git performance on big repos
Message-ID: <20080322142758.GT7991@mit.edu>
URL: https://gitlist.dev/e/20080322142758.GT7991%40mit.edu
In-Reply-To: <20080322162618.K47359@geo.geo.loc>

```
On Sat, Mar 22, 2008 at 04:34:22PM +0300, Fedor V. Sergeev wrote:
> Folks,
> 
> I'm trying to convert a relatively big Mercurial repo (70K commits)
> into Git using contrib/hg-to-git.  It initially goes fine but starts
> to slow down nearly exponentially as the number of converted
> changesets goes up.
> 
> git-fast-import seems to just hang around, while all the work (100% cpu)
> is spent in that python thing. It does not eat up memory, pstack looks
> fine, but after some 10K commits it just crawls.

I don't know if it will be better, but at the time when I needed to
convert e2fsprogs, I liked the results of hg-fast-export, found at:

        url = git://repo.or.cz/fast-export.git

You might hg-fast-import and see if it does any better for your repo.

Does it have a large number of branches or tags, by any chance?

     	       	     	       		   	 - Ted

```