Mini KDE for a Lightweight Desktop

First of all, I cleaned up my computer running Fedora Core 3. Partly, this was done to make some extra room, but the main reason was to build the packages in a clean environment. After some checking and thinking, I removed the following packages, which I originally had installed from Fedora Core or KDE/Red Hat repositories: kdeedu, kdeartwork, KOffice, kdesdk, kdevelop, kdepim, kde, kdebase, kdelibs and kdelibs-devel.

Here's the other reason to perform such trimming exercises: you can learn a lot about how packages relate to one another. Specifically, you discover unneeded dependencies and packaging errors that remain hidden when distributions simply bundle software together without paying attention. For example, I learned that, at least on Fedora, I couldn't remove redhat-menus-3.7.1-3.4.3.kde, because it is needed by apparently unrelated stuff, including htmlview, gnome-vfs, openoffice.org-1.1.2, Evolution, XMMS and Nautilus.

The same happened with arts, the modularized sound system for KDE, and its development complement, arts-devel. Users of older desktops certainly are able to survive, even when they have a sound card, without acoustic effects. However, those two packages are needed by many more applications, including gstreamer plugins, gnome-applets, Evolution and so on. Some of these dependencies do make sense once you find them, but others still make me wonder. In any case, there seems to be a lot of opportunities for space savings at this level.

After cleaning my hard disk, I installed the latest stable source RPMs of kdelibs, kdebase, kdepim and KOffice from apt.kde-redhat.org/apt/kde-redhat/all/SRPMS.stable. When I started, they were:

I chose the KDE for Red Hat Project instead of official Fedora Core packages, because I find them more polished than the standard ones. They also usually offer newer versions of the packages.

When you install a source RPM, you get all of the source code in a .tar.bz2 archive and the instructions to build everything in a .spec file. Normally, to build the package, you need to issue only the command:

rpmbuild -ba <package_name>.spec

To reduce disk space, I basically did two things, both relatively simple even for nonprogrammers. The first was to massage the compile and installation options in the .spec files. For example, I compiled everything without sound, adding -without-arts to the configure section. When available, I also added similar options to ignore other multimedia libraries or support for devices such as cell phones and PDAs. Then, I commented out all the Require and BuildRequires directives that check whether libraries for audio, video and modern peripherals are available before starting the process. I also removed the Provides directives for all the binaries I left out. Finally, I commented out the instructions that pack into the binary RPM files that I had not compiled or didn't need.

My complete .spec files are available in the Mini KDE section of the RULE Web site.

The second and most important trick was to insert a proper inst-apps file inside each KDE source tarball. It turns out that the configure scripts of these programs have a section that more or less says something like this (from kdelibs):

ac_topsubdirs=
if test -s $srcdir/inst-apps; then
  ac_topsubdirs="`cat $srcdir/inst-apps`"
elif test -s $srcdir/subdirs; then
  ac_topsubdirs="`cat $srcdir/subdirs`"
fi

$ac_topsubdirs is the list of all the subdirectories whose code must be compiled and installed. By default, this variable is loaded with everything written in the subdirs file. But, if you copy subdirs into inst-apps, remove from the latter all the unneeded items and then tar and compress everything again, only the applications you want are compiled. This also works when installing directly from source.

Generally speaking, to figure out what you could or could not remove from inst-apps, look at the README file in each subdirectory. The following is a short summary of what I did for each package.

I removed only the following items: arts, kdoctools, kate, libkscreensaver and doc. In the %configure section, I excluded xinerama, alsa and artsd support. I also commented out the Requires: arts directive, as well as those for jasper and openexr.