JamOLizer: Garbage Collection Visualizer in the JamVM

Garbage collection is a vital part of a virtual machine. However, the choice of garbage collector and its correct implementation is different for each type of system, especially real-time systems. It is hard to imagine what is happening internally within the garbage collector, which can lead to extremely fragmented systems or systems with degraded performance. GCspy [1] is a free visualization tool that attempts to improve our understanding of garbage collection. It is adaptable enough to be used in virtual machines written in Java, C or C++ and claims to be easy to use. JamVM [3] is a free, open-source Java Virtual Machine (JVM) that fully implements the JVM specification [5]. However, JamVM is also very lightweight and claims to leave a small memory footprint. The goal of our work is to incorporate GCSpy into the JamVM to visualize the memory footprint left by programs that it runs. Additionally, we will also be able to validate the effort needed to add GCspy to a virtual machine.