Interests, Difficulties, Sentiments, and Tool Usages of Concurrency Developers: A Large-Scale Study on Stack Overflow

Context Software developers are increasingly required to write concurrent code that is correct. However, they find correct concurrent programming challenging. To help these developers, it is necessary to understand concurrency topics they are interested in, their difficulty in finding answers for questions in these topics, their sentiment for these topics, and how they use concurrency tools and techniques to guarantee correctness. Interests, difficulties, sentiments, and tool usages of concurrency developers can affect their productivity. Objective In this work, we conduct a large-scale study on the entirety of Stack Overflow to understand interests, difficulties, sentiments, and tool usages of concurrency developers. Method To conduct this study, we take the following major steps. First, we develop a set of concurrency tags to extract concurrency questions and answers from Stack Overflow. Second, we group these questions and answers into concurrency topics, categories, and a topic hierarchy. Third, we analyze popularities, difficulties, and sentiments of these concurrency topics and their correlations. Fourth, we develop a set of race tool keywords to extract concurrency questions about data race tools and group these questions into race tool topics. We focus on data races because they are among the most prevalent concurrency bugs. Finally, we discuss the implications of our findings for the practice, research, and education of concurrent software development, investigate the relation of our findings with the findings of the previous work, and present a set of example questions that developers ask for each of our concurrency and tool topics as well as categories. Results A few findings of our study are: ¶ questions that concurrency developers ask can be grouped into a hierarchy with 27 concurrency topics under 8 ∗Corresponding author. Email addresses: mbagherzadeh@oakland.edu (Mehdi Bagherzadeh), sfahmed@oakland.edu (Syed Ahmed), ssripathi@oakland.edu (Srilakshmi Sripathi), raffi.khatchadourian@hunter.cuny.edu (Raffi Khatchadourian) Preprint submitted to Elsevier September 13, 2021 ar X iv :2 10 9. 03 13 8v 3 [ cs .S E ] 1 0 Se p 20 21 major categories, · thread safety is among the most popular concurrency topics and client-server concurrency is among the least popular, ̧ irreproducible behavior is among the most difficult topics and memory consistency is among the least difficult, 1 data scraping is among the most positive concurrency topics and irreproducible behavior is among the most negative, o root cause identification has the most number of questions for usage of data race tools and alternative use has the least. While some of our findings agree with those of previous work, others sharply contrast. Conclusion The results of our study can not only help concurrency developers but also concurrency educators and researchers to better decide where to focus their efforts, by trading off one concurrency topic against another.