To lock, or not to lock: That is the question

Mechanisms to control concurrent access over project artefacts are needed to execute the software development process in an organized way. These mechanisms are implemented by concurrency control policies in version control systems that may inhibit (i.e. ‘to lock’) or allow (i.e., ‘not to lock’) parallel development. This work presents a novel approach named Orion that analyzes the project's historical changes and suggests the most appropriate concurrency control policy for each software element. This suggestion aims at minimizing conflict situations and thus improving the productivity of the development team. In addition, it identifies critical elements that do not work well with any of these policies and are candidates to refactoring. We evaluated Orion through two experimental studies and the results, which indicated it was effective, led us to a prototype implementation. Apart from the Orion approach this paper also presents the planning, execution, and analysis stages of the evaluation, and details of prototype internals.

► SCM concurrency control policies may inhibit or allow parallel development.
► Correctly selecting these policies can improve the productivity of development teams.
► Orion analyzes historical changes to suggest appropriate policies.
► Orion was evaluated through two experimental studies.
► Tools implement the approach and enable a better visualization of Orion results.