APT and the art of high-quality slaughtery

Posted Mar 23, 2010 5:02 UTC (Tue) by sladen (guest, #27402)
In reply to: ATi 3D drivers? by nye
Parent article: Ubuntu 10.04 LTS Beta 1 released

The "they" are the primary authors/maintainers of APT; compare the names in:

Update-manager/do-release-upgrade exist to take care of higher-level upgrade concerns, such as changing the distribution name in /etc/apt/sources.list and coping with fundamental migrations like moving from IDE to SCSI/UUID device naming, Nvidia madness and boot-loader migrations. If you're comfortable undertaking those types of tasks yourself, you are free not to use it... Have a look at the following file and the signed tarballs of cleartext scripts referenced within in it for what type global workarounds are undertaken:

changelogs.ubuntu.com/meta-release-development

If you have encountered situations where you believe that the upgrade code has become unstable (or "brittle") then I'm sure that bug reports would be welcomed; the relevant place to report these appears to be:

bugs.launchpad.net/ubuntu/+source/update-manager/+filebug

APT and the art of high-quality slaughtery

Posted Mar 23, 2010 11:44 UTC (Tue) by nye (subscriber, #51576) [Link]

>Update-manager/do-release-upgrade exist to take care of higher-level upgrade concerns, such as changing the distribution name in /etc/apt/sources.list and coping with fundamental migrations like moving from IDE to SCSI/UUID device naming, Nvidia madness and boot-loader migrations.

These things should be documented somewhere *per release*, so that it's possible to know what this package is doing, and perform the upgrade manually.

>If you're comfortable undertaking those types of tasks yourself, you are free not to use it.

But this is a trap - as soon as you go there you must abandon all hope of any kind of support.

>Have a look at the following file and the signed tarballs of cleartext scripts referenced within in it for what type global workarounds are undertaken:

You are joking?
Picking the Lucid version, 'find . -path ./mo -prune -o -type f | wc -l' gives 224. That's 224 files to check, after excluding all the translations. On the plus side it does appear to be more comprehensible than the last version I tried to figure out (that was quite some time ago).

>If you have encountered situations where you believe that the upgrade code has become unstable (or "brittle") then I'm sure that bug reports would be welcomed;

Well I had a quick look at the bug list there to see if I could remember what it was that so incensed me about update-manager in my last frustrating attempt to use it. Though several of them are relevant, I believe the real culprit was #222732 - if at some point in the upgrade, update-manager is unable to download a file, it deletes everything it's downloaded so far and resets everything, without so much as a retry. Since this is almost guaranteed to happen, does that not seem like brittle behaviour to you?

(And note that that bug report is almost two years old. This package receives frequent updates and yet in effect may as well be unmaintained, because show-stopping problems are ignored. That practically *defines* Ubuntu in my experience.)