Analyzing Data Structure Growth Over Time to Facilitate Memory Leak Detection

Memory leaks are a major threat in modern software systems. They occur if objects are unintentionally kept alive longer than necessary and are often indicated by continuously growing data structures. While there are various state-of-the-art memory monitoring tools, most of them share two critical shortcomings: (1) They have no knowledge about the monitored application's data structures and (2) they support no or only rudimentary analysis of the application's data structures over time. This paper encompasses novel techniques to tackle both of these drawbacks. It presents a domain-specific language (DSL) that allows users to describe arbitrary data structures, as well as an algorithm to detect instances of these data structures in reconstructed heaps. In addition, we propose techniques and metrics to analyze and measure the evolution of data structure instances over time. This allows us to identify those instances that are most likely involved in a memory leak. These concepts have been integrated into AntTracks, a trace-based memory monitoring tool. We present our approach to detect memory leaks in several real-world applications, showing its applicability and feasibility.