The Pyramid-like Shape of Linux Kernel Authorship

jeremy · 03-22-2017, 08:26 PM

Quote:

In a recent paper accepted at 13th International Conference on Open Source Systems, we study code authorship in a large and long-lived system — the Linux kernel. Our goal is to identify authorship parameters from the Linux kernel evolution history, as well as interpret why they appear as such. We also check whether those parameters apply to the subsystem level, allowing us to assess their generality across different parts of the kernel.

Our analysis accounts for 56 stable releases (v2.6.12– v4.7), spanning a period of over 11 years of development (June, 2005–July, 2016).

Before presenting our study and its results, it is important to mention that our notion of authorship is broader than the English definition of the word. In the context of code, authorship relates to those who make significant changes to a target source code file. This may include the original file creator, as well as those who subsequently change it. Hence, different from authorship in books and scientific papers, code authorship is inherently dynamic as a software evolves.

File authorship follows a pyramid-like shape of increasing authority; at the top, Linus Torvalds acts as a “dictator”, centralizing authorship of most of the files (after all, he did create the kernel!). Bellow him lies his hand-picked “lieutenants”, often chosen on the basis of merit. Such organization directly reflects the Linux kernel contribution dynamics, which is itself a pyramid. However, as the kernel evolves, we see that Torvalds is becoming more “benevolent”. As Figure 2 shows, the percentage of files authored by Torvalds has reduced from 45% (first release) to 10% in v4.7.

Medium for more...

--jeremy