OHJ-1860 Software Systems Seminar: Global Software Development. Open-source software development By Antti Rasmus

Transcription

1 1 OHJ-1860 Software Systems Seminar: Global Software Development Open-source software development By Antti Rasmus

2 Outline 2 Open-source software (OSS) development Motivation: IDC study on open source in global software Case GNOME Architecture Organization Communication Case Apache

3 3 Open-Source Software Open-source software (OSS) is built by potentially large number of voluntary people a great babbling bazaar of differing agendas and approaches E. Raymond [1] There are supporting companies and paid developers as well Extreme case of globally distributed development Developer roles are not clearly defined or tasks aren't assigned Developers in arbitrary locations - rarely or never meet face to face Communication by means of mailing lists, forums, IRC, IM Lacks coordination: no plans, system-level design, schedules or defined processes? [2] However, software development management systems GNU Savannah, SourceForge, BountySource continues..

4 4 Open-Source Software Extreme case of globally distributed development Unknown people Multiple cultures and languages Because open source works in a distributed environment, it presents an opportunity for developing countries to participate in frontier innovation [3] Political differences Competition between developers Volunteers and company paid developers Despite of the bazaar nature, still high quality software! Apache, Linux kernel, GCC, Mozilla, Perl, GNOME,... Open-source ideology works great in distributed environment However, challenge for companies to fully exploit Different drivers, processes, licenses => Isolate OSS! [4]

5 5 IDC study on open-source in GSD IDC is global market intelligence firm Open Source in Global Software: Market Impact, Disruption, and Business Models, July 2006 [5] Surveyed 5,000 developers in 116 countries Conclusions OSS is the most significant all-encompassing and long-term trend that the software industry has seen since the early 1980s." OSS "play a role in the life-cycle of every major software category, and will fundamentally change the value proposition of packaged software for customers." OSS is being used by 71 percents of developers worldwide OSS is "in production" at 54 percent of the surveyed developers' organizations

6 6 Case GNOME Based on GNOME, a case of open source global software development by Daniel German, 2003 [6] GNOME project was founded in 1996 In 2003, 500 developers around the world, 2+ MLOCs Infrastructure GNU toolkit (gcc, make, emacs, etc.) CVS Bugzilla GNU Mailman Unix as development platform

7 7 Case GNOME - Requirement sources Vision: GNOME should be completely free software "free as in free speech" not "free as in free beer -Free Software Foundation Reference applications: GNOME should have most if not the same functionality as these reference applications MS Excel, gv, Outlook, Lotus Notes Asserted requirements Requirements gathered from general discussion on mailing lists, not necessarily from particular requirement analysis A prototype New feature ideas are frequently proposed in a form of a implemented prototypes. The rest decides whether to adapt it or not

8 8 Case GNOME - Architecture Big project is divided into manageable modules Four main groups of modules Libraries (19 modules) Core applications (4) Applications (16) Other (several dozens) At least one maintainer per module Oversees the development Coordinates and integrates the contributions of other developers If a module grows too big, it is broken into submodules Evolution (mail client) is broken into more than 20 modules UI, mail libraries, filter, importers, documentation, translation,...

9 9 Case GNOME - Module maintainer Module maintainers serve the roles of leaders provide vision divide their module into tasks attract developers to the project keep the project together and prevent forking The success of OSS project depends on the ability of its maintainers to divide it into parts which are small enough and independent, so that developers do not have to communicate developers' work has minimal impact to work of others

10 10 Case GNOME - The paid employees Several companies involved RedHat, Sun Microsystems, Ximian Paid employees are usually responsible for project design and coordination, testing, documentation and bug-fixing Usually less attractive to volunteers Companies make sure that development continues at a steady pace In the case of Evolution, the top 10 contributors (which account for almost 70% of the CVS commits) are all Ximian employees. Volunteers still play very important role maintainers, contributors, bug hunters, documenters, beta testers, etc. internationalization is only done by volunteers in GNOME

11 11 Case GNOME - Foundation In 2000, the GNOME Foundation was instituted Four entities members (any contributor) board of directors (11 democratically selected people) advisory board (non-profit organizations and companies) executive director Committees consist of volunteer developers for organizing conference, web site updating, system administration of GNOME machines, maintaining the membership list of the Foundation, etc. Release teams schedules module releases keeps track overall development of the project

12 12 Case GNOME - Communication Developers are distributed around the world Mailing lists for different purposes end users, particular modules, announcements is where the decision making happens IRC informal discussion without agenda Web sites lots of information for contributors GUADEC, the GNOME conference discussion, interaction and training GNOME summaries Posted to a mailing list in every two weeks news, most active modules and developers, numbers of bugs

13 13 Case Apache (in 2002) Apache is the most widely deployed web server [2] Almost 400 people contributed code CVS commits managed by Apache Group Apache Group started with 8 members in 1995 In 2002, 25 members in AG used exclusively mailing lists to communicate, and a minimal voting system A bug reporting system and a newsgroup that anyone could use were lower priority communication channels One AG member volunteers to be a release manager identifies critical problems preventing the release coordinates fixes and declares a version stable

14 14 References [1]The Cathedral and the Bazaar E.S. Raymond, [2] Two Case Studies of Open Source Software Development: Apache and Mozilla A. Mockus et al., ACM Transactions on Software Engineering and Methodology, Vol. 11, No. 3, July 2002, pp [3] Open-Source Software Development and Distributed Innovation B. Kogut, A. Metiu, Oxf Rev Econ Policy Vol. 17, No. 2, June 2001, pp [4] Global software development R Granat, Software Platforms, Nokia, August 2007 Online [5] Open Source in Global Software: Market Impact, Disruption, and Business Models Anthony C. Picardi, et al., July 2006 Summarized on Linuxdevices.com ( [6] The GNOME project: a case study of open source, global software development, Daniel M. German