[Python-Dev] Source control tools

[Andrew Bennetts]

On Thu, Jun 15, 2006 at 10:33:49PM +0200, Alexander Schremmer wrote:
> On Thu, 15 Jun 2006 19:00:09 +0200, Jan Claeys wrote:
> 
> > Op di, 13-06-2006 te 10:27 +0200, schreef Alexander Schremmer:
> >> Bazaar-NG seems to reach limits already when working on
> >> it's own code/repository. 
> > 
> > Canonical uses bzr to develop launchpad.net, which is a "little bit"
> > larger dan bzr itself, I suspect...?
> 
> I don't think so, without having seen the Launchpad code. I assume that
> Launchpad has less comitters (closed source!) and therefore less change
> sets and less parallel branches.

Actually, Launchpad's got twice as many lines of source (as measured by
sloccount), nearly 10 times as many versioned files, and about twice as many
revisions as bzr.

We typically have 10-20 parallel branches going through our review process at
any one time (branches are generally reviewed before they land on the trunk),
and probably many others being worked on at any given time.

> Once I pulled the bzr changesets (1-3 months ago) and it needed 3 hours on
> a 900 MHz machine with a high-speed (> 50 MBit) internet connection (and it
> was CPU bound). Note that bzr has gained a lot of speed since then, though.

That would have been when it was in "weave" format?  The current "knit" format
doesn't suffer the CPU problems in my experience.  It's still very slow over a
network because it does a very large number of round trips.  There's work to
greatly reduce that problem, by pipelining and by reducing the number of HTTP
requests (by issuing one request with a range header with many ranges, rather
than one request per range!).  There are also plans to write a smart server.

There's a big focus on performance improvements on the bzr list at the moment,
and they seem to be making rapid progress.

-Andrew.