The evolution of FreeBSD and linux

Abstract

Is the nature of Open Source Software (OSS) evolution fundamentally different from that of the traditional and commercially available software systems? Lehman and others conducted a series of empirical studies that found that traditional systems grow at a linear or sub-linear rate. A prior case study of the Linux OSS system suggests that OSS may evolve in a unique manner. Godfrey and Tu found that some aspects of Linux are growing at a super-linear rate rather than a sub-linear rate. Additional studies are necessary before drawing conclusions. Thus, we examine the evolution of FreeBSD and re-analyze the evolution of Linux, and find evidence that the growth of both systems has a linear upper bound, and thus appear to grow at similar rates to that of commercial systems. These results do not support the hypothesis that OSS systems grow at rates that exceed that of traditional systems.

Perpetual development: A model of the Linux kernel life cycle

“…Paulson et al claim that linear growth provides a good model [56], but this could be partly the result of using relatively short observation intervals of up to about a year and a half. Izurieta and Bieman also claim a linear growth rate for both FreeBSD and Linux [31].…”

“…Several authors have studied Linux growth, especially in connection with Lehman's Laws of software evolution [24,61,28,31,30]. This is also related to the potential increase in complexity, and the ensuing consequences regarding maintainability [64,63,65,30].…”

Analysis of the Linux Kernel Evolution Using Code Clone Coverage

“…Similar studies have been conducted in the past: Van Rysselberghe et al reconstructed the evolution of a software system using code-clone detection techniques [9]; Godfrey et al have conducted a thorough investigation of the evolution of the Linux kernel measuring various characteristics of the source code [2]; more recently, a similar study has been conducted by Izurieta et al [5].…”

Effort estimation of FLOSS projects: a study of the Linux kernel

“…As mentioned above, the case study is the Linux Kernel which has been previously studied several times and from several points of view ( [16], [17], [18], [19]). Two aspects are presented below: the first considers the whole evolution log of the Linux Kernel (since April 2005, when the overall data has been moved to the Git repository) and it displays the patterns of activity in terms of week-days and hours worked on by the Linux developers (irrespective of them being "core" or "peripheral" developers).…”