How many Ubuntu branches share history with upstream?

[James Westby]

On Wed, 10 Feb 2010 08:46:37 -0600, John Arbash Meinel <john at arbash-meinel.com> wrote:
> Where is this script going to be running? I wrote a trivial command that
> lets you run:
> 
>   bzr in-ancestry branch1 branch2
> 
> And reports back if the ancestry of branch1 is in branch2.
>   lp:~jameinel/+junk/bzr-in-ancestry
> 
> Running locally on bzr.dev trees, it takes less than 3 seconds to return
> true/false. Note also that the answer isn't symmetric. We've merged
> plugins into bzr.dev, but those plugins have not merged bzr.dev into them.
> 
> Similarly for packaging branches. I would imagine that the packaging
> branch might merge upstream, but not the other way around.
> 
> Comparing a mysql branch with a bzr.dev one seems to take 4s, which
> still isn't particularly long. I don't know what time scale you were
> hoping for

Certainly less than a day to run. 3s * 10,000 ~= 8 hours. It wouldn't be
near that to start with as we don't have anywhere near that number of
packaging links, but it's always useful to look at what would happen if
you scale.

> (but my experience with launchpad apis doesn't make it
> particularly faster than this ...)

True, but graphs can be done against the DB directly, which would be
much quicker as you don't have the https round trip overhead and it
gives you scope for writing queries that act on all projects at once.

Thanks,

James