Re: doc compilations: build-time or pre-built?

[Junichi Uekawa <dancer@netfort.gr.jp>]

Hi,

> > > It seems like it would be quite taxing on the autobuilders to have to pull
> > > something like docbook (and its chain of dependencies) into a pbuilder just
> > > to recompile a manpage that doesn't change between architectures.
> > > 
> > AIUI, the autobuilders use sbuild and don't purge the installed packages
> > unless the admins do so manually.  At least, that is what I have been
> > told on the subject.
> 
> No, that's not true; packages that are installed at the beginning of a
> build run are removed at the end. The main difference between pbuilder
> and sbuild is the fact that sbuild uses an existing chroot on which it
> works (or even builds in your "main" system if you have no chroot
> configured), while pbuilder creates a clean chroot environment based on
> a tarball with the required files before beginning a build, which it
> removes entirely afterwards.

I now know quite well that package installation time is a big
bottleneck.  My recent interests are in improving speed of pbuilder,
and I have been profiling execution times of cowbuilder.  If I can
eliminate the installation time altogether, I can make the time
overhead of using pbuilder over a normal 'debuild' pretty much like 2
seconds on a modern hardware).

I'm thinking about 

1. caching chroots with some common packages installed (there is a trade-off with accuracy)

2. improving speed of package installations through improving dpkg/apt execution time.


However, I'm not sure if I will have a good consolidated time to work
on this stuff before the next debconf :P.

regards,
	junichi
-- 
dancer@{debian.org,netfort.gr.jp}   Debian Project