A Fresh Approach to Understanding Distributed Applications

Most existing debuggers for distributed systems glue together a number of traditional sequential debug-gers. These architectures suffer from a number of deficiencies: the presence of a debugger on the tar-get machine may perturb the target program’s be-havior, and there are factors outside the purview of these debuggers that will affect system behavior. A pervasive debugger leverages a virtual machine monitor and runs each node of the distributed ap-plication in a separate virtual machine. By control-ling the entire execution environment, it is possible to minimize the probe effect and examine the en-tire distributed computation in a consistent state. Furthermore, interactions with the operating sys-tem and network can be analyzed.