Why software hangs and what can be done with it

Software hang is an annoying behavior and forms a major threat to the dependability of many software systems. To avoid software hang at the design phase or fix it in production runs, it is desirable to understand its characteristics. Unfortunately, to our knowledge, there is currently no comprehensive study on why software hangs and how to deal with it. In this paper, we study the reported hang-related bugs of four typical open-source software applications, aiming to gain insight into characteristics of software hang and provide some guidelines to fix them at the first place or remedy them in production runs.