Awareness and Merge Conflicts in Distributed Software Development

Abstract

Abstract-Collaborative software development requires programmers to coordinate their work and merge individual contributions into a consistent shared code base. Traditionally, coordination follows a series of "update-modify-commit" cycles, where merge conflicts arise upon committing if individual modifications have diverged and must be explicitly reconciled. Researchers have been suggesting that providing timely awareness information about "who's changing what" may not only help deal with conflicts but, more generally, improve the effectiveness of collaboration.This paper investigates the impact of awareness information in the context of globally distributed software development. Based on an analysis of data from 105 student developers constituting 12 development teams located in different countries, we analyze, among other things: 1) the frequency of merge conflicts and insufficient awareness; 2) the impact of distribution on team awareness; 3) the perceived impact of conflicts and lack of awareness on productivity, motivation, and project punctuality. Our findings include: 1) lack of awareness occurs more frequently than merge conflicts; 2) information about remote team members is missing roughly as often as information about co-located ones; 3) insufficient awareness information affects more negatively programmer's performance than merge conflicts.

Predicting Merge Conflicts in Collaborative Software Development

“…In this paper, we investigate merge-conflict prediction by creating a list of nine feature sets that can potentially impact conflicts. Our list is based on previous work in the areas of software merging and code review [5], [9], [13], [34], [35]. Our work is different from all the above in that we use statistical machine learning to create a classifier, for each programming language, that can predict conflicts in unseen merge scenarios.…”

“…Given the cost of merge conflicts and integration problems, many research efforts have advocated earlier resolution of conflicts [5], [7], [8]. Previous work has shown that lack of awareness of changes being done by other developers can cause conflicts [9], and since infrequent merging can decrease awareness, it increases the chance of conflicts. To address that, proactive merge-conflict detection warns developers about possible conflicts before they actually attempt to merge, i.e., before they try to push their changes or pull new changes.…”

“…added and deleted lines in a branch [13], [35] More code changes may increase the chance of conflicts 2 6 No. of active developers in a branch [9], [34], [35] Having more developers increases the chances of getting inconsistent changes 1 7…”

“…Duration of the developement of the branch in hours [9] The longer a branch exists for, the more likely it is for inconsistent changes to happen in one of the other branches 1 Total number of features: 28 imbalanced data. Specifically, we use Random Forest, which is an ensemble tree-based classification method.…”

Handling Disturbance and Awareness of Concurrent Updates in a Collaborative Editor

“…Awareness during distributed collaboration has got wide attention for many years, such as in the context of collaborative software development [3,4,10]. A recent study suggests that "developers would appreciate having access to awareness information frequently but not in real time; they have, however, diverse preferences regarding the level of detail in which such information should be made available" [3]. Without the mechanisms for collaborative editing, tools typically provide information about concurrent updates with coarse granularity, such as at a per-file level [10].…”