6.5. Maintenance

It is an advantage to the project to for each area of the source have at least one person that knows this area well. Some parts of the code have designated maintainers. Others have de-facto maintainers, and some parts of the system do not have maintainers. The maintainer is usually a person from the sub-project that wrote and integrated the code, or someone who has ported it from the platform it was written for. [10] The maintainer's job is to make sure the code is in sync with the project the code comes from if it is contributed code, and apply patches submitted by the community or write fixes to issues that are discovered.

The main bulk of work that is put into the FreeBSD project is maintenance. [Jørgensen, 2001] has made a figure showing the life cycle of changes.

Jørgenssen's model for change integration

StageNext if successfulNext if unsuccessful
reviewpre-commit testcode
pre-commit testdevelopment releasecode
development releaseparallel debuggingcode
parallel debuggingproduction releasecode
production release code

Here development release refers to the -CURRENT branch while production release refers to the -STABLE branch. The pre-commit test is the functional testing by peer developers when asked to do so or trying out the code to determine the status of the sub-project. Parallel debugging is the functional testing that can trigger more review, and debugging when the code is included in the -CURRENT branch.

As of this writing, there were 269 committers in the project. When they commit a change to a branch, that constitutes a new release. It is very common for users in the community to track a particular branch. The immediate existence of a new release makes the changes widely available right away and allows for rapid feedback from the community. This also gives the community the response time they expect on issues that are of importance to them. This makes the community more engaged, and thus allows for more and better feedback that again spurs more maintenance and ultimately should create a better product.

Before making changes to code in parts of the tree that has a history unknown to the committer, the committer is required to read the commit logs to see why certain features are implemented the way they are in order not to make mistakes that have previously either been thought through or resolved.

[10] sendmail and named are examples of code that has been merged from other platforms.

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