[lug] The issues of separate /home partitions, or maybe just freedesktop/SuSE problems?

[Chris Riddoch]

Hi, everyone.  First, sorry for the length - I'm including details I
believe may be relevant to diagnosing this issue.

I once heard the advice of using separate partitions for /home in
order to ease upgrades - the / partition can be wiped and reinstalled
from scratch, and the personal data on /home is unaffected by a fresh
install.  It seemed like a great idea.  I'm wondering, though, if this
might be responsible for some really broken behavior.

First, the setup:  Two separate systems, both running OpenSuSE 11.1,
both with separate /home partitions.  One system was reinstalled
(except /home, naturally) from 11.0, the other from 10.1.  The 10.1
system's original hardware was retired, disk moved to newer hardware,
and the reinstall conducted on new hardware - also leaving the /home
partition untouched.  The first system, an IBM T40 thinkpad, has ATI
video.  The other, nvidia.  (This could matter, later.)  Both have
been running XFCE as the primary desktop environment, but various
gnome and KDE programs are used to get stuff done.

The potential disadvantage of using a separate /home partition this
way is that the newer software installed is expected to appropriately
handle the presence of older configuration files, either by upgrading
them automatically or erroring out noisily when there's a problem.
It'd be ideal if the software, on detecting unusably old config files,
would at least suggest that certain files/directories be removed so
that a fresh, default configuration can be created, as it would be on
a new install when the program is run for the first time.  Alas, it's
evidently too much to expect from our desktop environments.

It seems that some freedesktop.org stuff doesn't handle this
gracefully.  The main application hierarchy menus have been behaving
very unpredictably - the system upgraded from 11.0 decided not to show
the 'games' menu at all following the installation of a game.  The
other, previously 10.1-based, lost most menu items altogether.  Many
applications still aren't being presented in the menus on either
system.  Other menu items are multiplying at random.

Relatedly, the file-type associations for opening things from file
managers, be it nautilus, konqueror, or dolphin, are frequently
broken, and unfixable with the 'use this program for this file type'
option, as many programs we'd want to use aren't in the menus, or are
with incorrect paths.  For example: /usr/X11R6/bin/OOo-writer doesn't
exist on modern SuSE.  It's /usr/bin/owriter now, but you wouldn't
know it from the menus.  Everything relating to menus in /etc was
deleted and recreated by the installs.

Separate /home partitions may also be related to another issue: both
systems are having is problems shutting down properly.  First, when
the shutdown splash screen is about to be displayed, the video is
corrupted - usually displaying something that had previously been on
the screen, in wild distortions, on both systems, with completely
different video hardware.  This made it hard to tell that filesystems
weren't being unmounted properly, and that the system would hang while
attempting to unmount.  On the T40, this happens every *other* boot,
curiously.  It's difficult to diagnose, because without a serial port,
it's rather hard to have a serial console to send things to instead of
the screen that's having its own, probably unrelated, issues.

With some googling, I found references to other people with similar
shutdown problems, who *also* have separated /home partitions from /,
and the problems have been attributed to jexec[1] and JRE, or
beagle[2], (both of which we don't have installed) or pulseaudio[3],
or even something having to do with xsession[4].  It sure *looks*
rather scattershot, and separate /home partitions seem common between
many of these cases.

So: what should I blow away from our home directories, with the
expectation that the desktop environment will start up thinking it's
new, and just work?  There's so many of them that I don't even know
what half of these dotfiles/dotdirectories *are*, anymore.   Mere
deleting might not be sufficient, either - in not too-distant memory,
gconfd would recreate files from its memory cache to defeat tinkering
users like myself from trying to solve these kinds of problems.

[1] http://forums.opensuse.org/applications/402963-strange-issues-suse-11-1-gnome.html
[2] http://forums.opensuse.org/install-boot-login/406790-shutdown-problems-solution.html
[3] http://www.broadbandreports.com/forum/r21601264-openSUSE-111-is-out~start=20
[4] http://groups.google.com/group/alt.os.linux.suse/msg/21e537985b3b6a0d

-- 
Chris Riddoch