[darcs-users] current status of darcs

[David Roundy]

On Mon, Mar 05, 2007 at 07:09:44PM -0800, William Morgan wrote:
> Hi all,
> 
> A project I'm working on wants to switch away from CVS to SVN. I'm
> thinking about recommending darcs to them instead. I can make many
> convincing arguments for the usefulness of distributed, changset-based
> VC, but what I don't have a sense of is how stable and reliable darcs
> is. I'll be in big trouble if things go awry. :)
> 
> In particular:
> 
> 1. The first question on the FAQ mentions certain types of conflicts can
>    cause darcs to hang. It then points to a bugreport that is a year
>    old. Is this still an issue? Is it a common occurrence? In such a
>    situation, is it easy to solve, or difficult?

It depends on your use patterns.  In "ordinary" use patterns, darcs works
fine.  There are, however, pathological use patterns (which really do show
up in practice) that can cause trouble.  In particular, maintaining a
parallel branch with significant resolved conflicts will eventually cause
trouble.

That said, in the history of darcs itself, this has only happened once.

I should also mention that you can run into resource-exhaustion trouble if
you've got a project that is very large.  e.g. the linux kernel would cause
trouble.  Eventually, we need to go back and re-optimize darcs for large
repositories, but it's just not high enough priority--particularly because
that sort of change can introduce bugs.

> 2. How actively maintained is darcs? Is it losing steam? Are bugs being
>    fixed faster than they're being introduced? The last release was 10
>    months ago---that could be a good sign or a bad one.

It's actively maintained, and the slowness of releases is a mix of the main
developers being rather busy with other things, and darcs being pretty
mature.  In general, there's very little to fix, except the above-mentioned
conflicts issue, which is being worked on, but is taking time.

> 3. I've seen mentions of using Tailor to back up darcs into e.g. CVS.
>    This would certainly help people feel more comfortable, but how
>    reliable is such a setup?

I've heard good things about tailor, but to be honest, backing up isn't
really going to gain you anything.  Darcs doesn't lose your history, so if
you run into trouble later (e.g. performance or conflicts) you could always
use tailor to switch to something else at that time.
-- 
David Roundy
Department of Physics
Oregon State University