2 Debian Code Search: An Overview

4.2.4 Popularity contest
4.2 Ranking
The Debian “popcon” (short for Package Popularity Contest) project was registered in 2003 to
generate statistics regarding which packages are in use in Debian [13] . Users of Debian who
have internet access can opt-in to this project by installing the package popularity-contest.
The Debian installer also offers to install this package when installing a new machine. The
popularity-contest package contains a script which is run once a week and uploads
statistics about the installed packages to Debian servers.
In this work, only one aspect of the popcon data has been used: the package installation
count. This figure describes how many different machines have installed the package in
question. Each machine is identified by a 128-bit UUID [14] .
From here on, inst(x) is defined as the number of installations of package x.
Since popcon is an opt-in mechanism, the numbers are to be taken with a grain of salt. The
amount of submissions as of 2012-07-13 is about 120 000 4 . This is a substantial number, but
not necessarily representative.
While there are similar databases in other Linux distributions, most notably Ubuntu, which
also uses popcon, these have not been used in this work for various reasons: other data is
not as easily available as Debian popcon data is. The latter has been taken from UDD, the
Ultimate Debian Database [12] . Furthermore, when using data from other Linux distributions,
package availability 5 and package names often differ.
4 http://popcon.debian.org/stat/sub-***.png [sic!]
5 Software installed without using the package system is not tracked by popcon or any other such database
that I know of.
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