The Whole is Less than the Sum of the Parts

I have been using Ubuntu since the days of Warty, but I am yet to experience a smooth upgrade from one version to another. After the past experiences of a Windows partition being rendered unbootable (twice), and X server not starting (always) after Ubuntu updates, today I have reached a new low with the system being left completely unbootable.

I have taken great care to follow the Ubuntu instructions, and all seemed to run rather smoothly to start with; after about an hour of downloading and another or so of installing, the Update Manager finished. I was expecting the system to reboot, but it did not. There was no disk activity, and quick check verified that the update process was indeed gone; the system appeared to be functional on the surface, but various applications would not run without any error message; this included Update Manager itself, and the shutdown command. So I have resorted to a ‘hard’ shutdown (something that I expect all ATI driver users have experience with anyway), and restarted. The kernel decompressed, and then just sat there. I have tried two other kernels that grub would let me access, in normal and emergency mode, but without success, just few more messages, the last of which said, ‘waiting for root file system’.

At the end I booted up my wife’s computer, downloaded the Ubuntu installation CD image and booted from it; on past experience with the Ubuntu CD I was expecting to loose the contents of the partition on which the original rootfs lived, so I was pleasantly surprised when the live CD just worked. I mounted the original rootfs under /mnt and chrooted under there; apt-get check revealed that ‘dpkg was interrupted’ (presumably something crashed ?) and suggested running ‘dpkg –configure -a’. This looked promising, and after rerunning it with –force-depends to get around not being able to run some post install scripts correctly, I got a system that, while not completely fixed, nevertheless successfully booted (even the X server started!). Then one more round of dpkg –configure -a, and building of the ATI proprietary drivers (why, o why, when Ubuntu is distributing these, they cannot keep them reasonably current?), and behold, eight hours later, I have a Feisty. Now I just have to purify it by removing OpenOffice (long live AbiWord and Gnumeric!) and Evolution (for some reason I prefer the intelligent design of Thunderbird).

Over the past few weeks I have been coming to grips with git-svn, and git in general. Two reasons in particular led me to jumping on the git bandwagon. First of all, although I like the simplicity of svn, I have ever increasing number of svn checkouts around, taking more of my diskspace than I am happy about; as it happens, git is much more efficient in disk usage than svn, and the savings I have made by moving my svn repos to git-svn have been significant.

The second reason, and probably the more significant one, is that git makes it much easier to work with multiple branches, in particular, to create private local branches with proper history tracking, in which I can work on all kinds of unstable features that I do not want to pollute the public repo with, yet that are sufficiently complex to benefit from being able to commit in small step, revert, etc. The git merge works extremely well (except for change logs, see below), so that keeping my local branches in sync with the remote repo has proved very easy.

Admittedly, the git learning curve is steep, especially if coming from a CVS / SVN background, as most of the git commands bear no resemblance to the cvs interface (not really surprising as git is quite different under the hood from either), and the man pages are of varying quality (and generally assume that you know how to use git). So, here are some git/git-svn notes for gits like me: Read the rest »