IEEE Spectrum February, 2014 - 72

DATAFLOW_

Who's PAying The Bills? While volunteer contributors still represent a plurality among
developers, over 80 percent of code is contributed by people who are paid for their work. The Linux
Foundation notes that contributions have been increasing from companies that make mobile and
embedded systems, such as Linaro, Samsung, and Texas Instruments.

Changes

The AuThors

h. hartley sweeten

These are the
programmers who
have contributed
the most code
updates to versions
3.2 through 3.10.

2107

Mark Brown

1418

Al Viro

1311

Axel lin

1078

Johannes Berg

926

A systems integration
engineer at Vision
Engraving Systems,
Sweeten has been a
maintainer of Linux's
support for ARM-based
chips since 2009.

Company

Sign-offs

red hat

20 369

linux Foundation

9561

intel

7244

google

4605

none (volunteers)

4155

suse

3275

samsung

2684

Wolfson Microelectronics

2474

Texas instruments
iBM

2372
2245

The gATekeePers

Contributions from individual
developers must have sign-offs before being incorporated
into the official kernel code. Here corporate employees truly
dominate, with just over 5 percent of approvals by volunteers.

LINES OF CODE

16 000 000

15 000 000

VERSION
3.0

3.1

3.2

3.3

3.4

3.5

3.6

3.7

3.8

3.9

3.10

The groWing kernel The increasing size of the Linux kernel is due to the incorporation of significant new features, including a file
system optimized for solid-state drives and support for the 64-bit ARM microprocessors used in embedded and mobile devices.
72

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FEB 2014

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nOrTh AmEricAn

|

SPEcTrUm.iEEE.OrG

IlluStratIon by mckibillo

Source: "Linux KerneL DeveLopment: How FaSt it iS GoinG, wHo iS DoinG it, wHat tHey are DoinG, anD wHo iS SponSorinG it," Linux FounDation, 2013.

google / 2255

samsung / 2415

8108

iBM / 2858

9483

unknown / 3032

12 550

intel

suse / 3212

red hat

About once a year, the Linux Foundation analyzes
the online repository that holds the source code of the
kernel, or core, of the Linux operating system. As well as
tracking the increasing complexity of the ever-evolving
kernel over a series of releases from versions 3.0 to 3.10,
the report also reveals who is contributing code, and
the dominant role corporations now play in what began
as an all-volunteer project in 1991. -Stephen CaSS

linaro / 3791

none
(volunteers)

Texas instruments / 3814

Changes

Company

Who's
Writing Linux?
Corporate-sponsored
programmers
dominate



http://SPEcTrUm.iEEE.OrG

Table of Contents for the Digital Edition of IEEE Spectrum February, 2014

IEEE Spectrum February, 2014 - Cover1
IEEE Spectrum February, 2014 - Cover2
IEEE Spectrum February, 2014 - 1
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IEEE Spectrum February, 2014 - 71
IEEE Spectrum February, 2014 - 72
IEEE Spectrum February, 2014 - Cover3
IEEE Spectrum February, 2014 - Cover4
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