An investigation of semantic checkpointing in dynamically reconfigurable applications

Abstract

As convergence continues to blur lines between different hardware and software platforms, distributed systems are becoming increasingly important. With this rise in the use of such systems, the ability to provide continuous functionality to the user under varying conditions and across different platforms becomes important.This thesis investigates the issues that must be dealt with in implementing a system performing dynamic reconfiguration by enabling semantic checkpointing: capturing application level state. The reconfiguration under question is not restricted to replacement of a few modules or moving modules from one machine to another. The individual components can be completely changed as long as the configuration provides identical higher-level functionality. As part of this thesis work, I have implemented a model application that supports semantic checkpointing and is capable of functioning even after a reconfiguration. This application will serve as an illustrative example of a system that provides these capabilities and demonstrates various types of reconfigurations. In addition, the application allows easy understanding and investigation of the issues involved in providing application-level checkpointing and reconfiguration support. While the details of the checkpointing and reconfiguration will be application specific, there are many common features that all runtime reconfigurable applications share. The aim of this thesis is to use this application implementation to highlight these common features. Furthermore, I use our approach as a means to derive more general guidelines and strategies that could be combined to create a complete framework for enabling such behavior.