Re: xz-compressed control metadata
On Sat, 2012-11-03 at 21:56:12 +0100, Philipp Kern wrote:
> are there plans on the dpkg side to support other compression methods
> for the control.tar in .deb files? Some of the d-i udebs have large
> debconf templates which are only compressed with gzip, while xz would
> yield smaller udebs.
This is something that crossed my mind when I thought about considering
changelog and copyright as dpkg metadata files as those tend to be big,
and when moved to the control member, they would benefit from better
compression methods. I don't really know what was the rationale for
adding other compressors support only for the data member, because
those archives cannot be extracted with really old tools anyway, *but*
their metadata could still be analyzed, although that does not seem
like a much compelling argument to me.
One problem is that I don't really feel like adding options to select
the compressor for each different ar member, so if the compressor is
global it means it cannot be switched to compress the control member
with anything other than gzip until a dpkg supporting unpacking that
is in stable, which would seem to be too late for that now (barring
an exception from the RT of course, althought that might still require
string changes which would be pretty annoying). And special casing
udebs is not an option either, because dpkg-deb does not have any
kind of knowledge about them in the first place.
> As far as I know control.tar.gz is hardcoded in various places, though.
And there's that too.