Back to Uni

I managed to finish the first week back after the University mid semester Holidays. Only got 3 new assignments meaning I have 4 from 4 Computer Science classes.

Isaac showed me darcs and I've been playing with that to manage an interpreter I've been writing.

Frozen Bubble

I have to say frozen bubble is too addictive. I was up until 2:20 this morning playing it. Next I'll have to try and finish all 100 levels as I only got to somewhere around 55.

More on delta packages

I've been looking at delta packages for Debian based systems more tonight.

Early tests seem to point to generating a delta of the data.tar file contained within the archive[1].

I tested the xbase-clients package from Ubuntu 4.10.
Each .deb file is around 1.9M each.
* A bsdiff of the 2 .deb files generates a 1.7M file [2]
* A bsdiff of the 2 data.tar.gz (the actual package) files was about the same
* But bsdiff produced a 78k diff when I gunziped each data.tar.gz

I will now investigate with more packages from my download cache if this is the case with other packages or if this was just a fluke.

[1] .deb files can be extracted with "ar -x file"
[2] gzip will introduce a cascading effect with every change making any binary update system ineffective if it relies on finding any common sections (e.g. bsdiff, rsync)

Random Ubuntu freezings

Ubuntu is currently deciding it will freeze everything in X except the mouse at random times.

This is very rare as it has only happened once before over a month ago. I will have to have a look at it with ssh if it happens again and will let me get in.

Ubuntu update

I decided to pre-download the updates for Ubuntu 5.04.

apt-get makes this an easy task as all I did was:

• create a new sources.list with only hoary resporitories
• sudo apt-get -o Dir::Etc::SourceList=./sources.list --just-print upgrade
• sudo apt-get -o Dir::Etc::SourceList=./sources.list -d update

The --just-print may not have been needed but I added it as I wasn't sure and didn't wan't to kill my current system as I'm on dialup.

Now I just have to wait for about 240Mb of packages to download, if only they used delta packages (packages containing only the changes) or just send the deltas to the version released (just the changes between the package files). Both couls be obtained with bsdiff & bspatch