Seems my XFS file system is a little hungry. Now three times after Linux crashed I found a few of my files with a filesize of 0 after the reboot, namely gconf database and Wine registry, both of which where likely opened at the time of the crash. The crashes themselves should be unrelated, since they look like standard OpenGL + instable driver issues and are more or less reproducible. Haven't looked that deep into the issue, but it looks like I have to replace XFS with something that doesn't destroy files that easily, since this is getting annoying.
Update1: As far as I understand the issue now:
- it is expected behavior
- it is caused by "write cache" being enabled and
- it is caused by "write barriers" not being supported by the device mapper
Solution? Disable "write cache" with hdparm it seems.
Update2: Even so I have disabled the "write cache" on my HDD, it seems I am still losing files on crashes. Gimp's recent files and Gnomes File-Dialog bookmarks have gone missing (~/.recently-used.xbel, ~/.gtk-bookmarks).
I really don't like this.