bzr-svn branches

[Jelmer Vernooij]

Russel Winder wrote:
> Jelmer,
> 
> On Wed, 2009-04-08 at 13:01 +0200, Jelmer Vernooij wrote:
> 
>>> Are you tracking bzr.dev so all changes to bzr.dev are in this branch?
>> Yep. It should usually be up to date
> 
> OK, I may well give it a try as a drop in replacement.  Fingers
> crossed :-)
> 
>>> What are the fixes that make Subversion access so much faster?  If there
>>> are so efficacious, why aren't then in bzr.dev?
>> They are pending to be included in bzr.dev, but they still need to be
>> reviewed, possibly fixed and then merged. This branch contains a
>> "preview" of those changes.
> 
> Splendid.
> 
> Is there a short explanation of how you got the Subversion interaction
> down by such a huge factor?
The most important patch to bzr allow furthers customization (and thus
optimization) of the way pulling between branches of different formats
is done. This makes two things possible in bzr-svn:

 * Subversion (obviously) doesn't store per-branch revision numbers so
bzr-svn had to calculate them by walking history. bzr-svn now ships with
a version of pull() that avoids revision numbers altogether when dealing
with svn and just calculates them once revisions have been pulled

 * Only recent tags are fetched when pulling from Subversion, rather
than all tags (finding all tags required looking at the full branch
history in Subversion)

Cheers,

Jelmer