migrating from CVS

[Martin Pool]

On 7 Mar 2006, at 09:14 , Jos Backus wrote:

> I'd like to say thanks to everybody answering my questions so far.  
> Migrating
> to a new VCS is not a project undertaken lightly so we are trying  
> to be as
> well-prepared as possible selecting a suitable successor.
>
> Besides looking at features that distinguish Bazaar-NG from CVS/ 
> Subversion, of
> importance to us is a sense of how "production-ready" Bazaar-NG is.
>
> In particular:
> - Stability of the storage/repository format. Having to make  
> disruptive
>   changes to repositories would be a bad thing, and I'm happy to  
> see that that
>   the release roadmap says that the storage format should remain  
> stable for
>   the next year after 0.8 is released.

We're using it in production for development at Canonical.  It's not  
"set and forget" yet -- svn has had bugs shaken out for several more  
years.

> Are any other major repository format
> changes being planned the would potentially impact production sites?

We don't have any plans to do such a thing.  Whether we end up  
changing depends on how 0.8 fares in the real world.  It's fairly  
unlikely we'll have any mandatory changes -- we may offer new options  
in future releases that are better in some way.

> - Size of the source code base Bazaar-NG can handle reliably  
> without slowing
>   down to a crawl. How safe is it to migrate a CVS repository with  
> a dozen or
>   so modules containing thousands of files each? Has Bazaar-NG been  
> tested
>   against such large repositories?

It has been tested and used on such trees; we do have some  
performance problems on large trees that we're working to fix.
>
> Do you think Bazaar-Ng is ready for this type of (heavy) use,  
> replacing CVS?
> Or would we at this time be better off switching to Subversion  
> (even though
> its featureset is limited by comparison)? Or alternatively, would  
> you say that
> Bazaar-NG isn't quite there yet but wil be soon, so we should hold  
> off (a few
> more months) if we can?
>
> I realize these are difficult questions and ultimately nobody else  
> but us can
> make the decision. But your opinions are very valuable nontheless.  
> Comments
> appreciated.

 From what you've said, my suggestion would be to try it out on your  
code and give us feedback on what you discover, and plan to migrate  
in a few months rather than immediately.  There is a certain amount  
of working in migrating to any new system, which would make me  
disinclined to shift a large existing project to svn unless I was  
fairly sure svn had everything I'd want for the next few years.

-- 
Martin Pool