Of Debian Etch’s quality and release schedule

December 20th, 2006 by lucas

The delay of Debian Etch caught some bad press this week. Some articles compare Debian to Ubuntu (which tries hard to have fixed-time releases), and some bloggers are amused by the fact that the next Debian release was delayed “again”. There are some important points though:

  • Etch wasn’t really scheduled to be released on Dec 4th. This target date was mainly used to determine other dates in the release process, like the freeze dates.
  • Ubuntu Dapper was delayed as well, for 6 weeks. Ubuntu Edgy wasn’t delayed, but I don’t think anybody can seriously compare Ubuntu Edgy’s quality with the upcoming Debian etch’s quality: edgy was more like a technology preview.

Now, the question is: how good is Debian Etch compared to Ubuntu Dapper ? It’s difficult to compare distributions: there aren’t a lot of good metrics for this. Of course, one could compare the number of packages that fail to build from source (it’s a good indicator of something seriously wrong in a package). But a lot of work has been done on etch about this, so it wouldn’t really be fair for Ubuntu. A good alternative is debcheck.

debcheck checks that packages can be installed (i.e that their dependancies can be satisfied). It does so by analyzing the content of the Packages files. I compared the results of debcheck on etch as of today (I re-processed it, but the same results are available from qa.d.o), and of debcheck on Dapper (not including dapper-updates – I wanted to compare quality at release date). Included sections were main for etch, and main, restricted and universe for dapper (I didn’t want to consider non-free packages, since their quality tend to be lower).

Results:

4 packages have unsatisfiable Depends on etch, on i386. 49 have unsatisfiable Recommends.

In the main section of Dapper, still on i386, only one package has a problem with its Depends (it was psycopg, because its binary package python2.3-psycopg has a dependancy on python2.3-egenix-mxdatetime). 46 packages in main had unsatisfiable Recommends. This is better than Etch, of course, but Ubuntu/main is much smaller than Debian/main.

When restricted and universe are included, the results are much worse. 80 packages have unsatisfiable Depends, and 150 packages have unsatisfiable Recommends. It is worth noting that those numbers are worse than those of Debian unstable as of today (67 packages have unsat Depends, 34 have unsat Recommends).

Conclusions (sort of):

  • Using the debcheck metric (which is actually quite important, since it translates in uninstallable packages for the users), Debian etch is already of better quality than Ubuntu Dapper when it was released (again, I haven’t checked with dapper-updates included).
  • It would be great to integrate such tests into the Ubuntu release process. Fixing bug is good, but such tools help to improve the distribution quality as a whole. I’ll try to work on this for Feisty after the Etch release.

3 Responses to “Of Debian Etch’s quality and release schedule”

  1. Simon wrote on 12/21/06 at 12:07 am :

    Nice work, thanks!

  2. Matthew East wrote on 12/21/06 at 2:14 am :

    Isn’t that what this does:

    http://people.ubuntu.com/~cjwatson/testing/

    Linked from https://wiki.ubuntu.com/DeveloperResources

    Maybe I haven’t quite understood the test you are proposing.

  3. Jonathan Carter wrote on 12/21/06 at 11:13 am :

    This is quite cool for two reasons. Firstly, it shows that Ubuntu’s main component is of very high quality. Secondly, it shows that Debian maintains a very high quality over a much larger ‘main’ archive. At least Ubuntu’s main is getting bigger with every release. Hopefully the quality will be sustained.