[boost] Re: Moving from CVS to Subversion?

From: David Abrahams (dave_at_[hidden])
Date: 2005-02-04 09:44:18

Walter Landry <wlandry_at_[hidden]> writes:

> I think that svn is the logical choice if you want to stay with a
> centralized model.  I just don't think that the centralized model is
> the best way.  

If there's no central repository, how do you know what the "real"
state of the codebase is?  How does it get backed up?  How does
decentralization interact with automated testing?

> The distributed alternatives all have issues, but you have to weigh
> that against the problems with a centralized model.  Obviously, the
> centralized model is not a deal-breaker, because Boost has been
> surviving with CVS.  But it is important to understand what kind of
> problems you will have with any centralized model.
>
> For example, from a different email you wrote
>
>   I don't have much to say other than to say that some of us spend a
>   lot of time waiting for CVS,
>
> What kind of operations are you doing that require waiting?  

Update, for one.  And for that one substantial churn happens on the
local machine before any bits move across the network.

The others usually require some mildly annoying wait, too, but that's
the biggie.

> Some operations in distributed systems do not require talking to the
> central server at all.  Even "update" will differ because the work
> patterns are different.  

Details?

> In any case, getting a new host (OSL) may solve some of this.

Maybe, but as I've been saying, the problems with update are
substantially due to the way CVS works.

>   there are constant stale locks,
>
> This problem mostly goes away with distributed systems.

And completely goes away with SVN.

>   our occasional file moves are painful,
>
> This goes away with any modern version control system.
>
>   and the anonymous pserver image lags the real one by an hour or
>   more.  Oh, and SF's connection for getting the CVS tarball keeps
>   dropping, so it's hard for anyone to do automated backups.
>
> These sound more like problems with sourceforge, not the version
> control system.

Yes.

> So it really sounds like you should see how well the new host works
> with CVS before committing to svn.

That's an interesting thought.

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com