Process Migration techniques have been around since the early days of Networked Operating Systems. However, process migration has not been widely adopted in software architecture design due to performance cost and unfeasible applications domain at that time. The emergence of new mobile computing technology is now the driving force to investigate new migration models that will support mobile applications and will help to optimise the available scarce resources that are a feature of the mobile computing environment. New alternatives to process migration have been developed and are attracting more researchers. These alternatives include remote execution, process cloning, mobile agents, and mobile code systems. They are simpler to implement and more inexpensive in their overhead cost to the execution environment. This thesis investigates the design and a reference implementation of a framework to support application designers in building adaptive migratory applications. The framework is called Camel. For applications to migrate they need to capture/save their states so that they can be restarted at the new location. However, capturing/saving mechanism of low level execution state imposes great performance cost on applications and are not necessarily required for migration. In Camel we argue that applications can migrate successfully with no need for low level execution state and with minimum application state, if the application designer decides on the necessary state at design time. The design of adaptive migratory applications requires infrastructure support for monitoring the execution environment so that applications can be notified of any changes in a critical resource that might trigger migration, adaptation or a combination of both. Monitoring a critical resource is accomplished through the use of the monitor component of Camel. In this work we only focus on monitoring of memory and application throughput. The framework provides support for the application designer to construct adaptation at design time through the provision of a common framework of helper objects and classes. The designer can then tweak the behaviour of the application through a set of policy profiles to better utilise critical resources
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:405974 |
| Date | January 2004 |
| Creators | Al Bar, A. M. |
| Publisher | University of Sussex |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
Page generated in 0.0024 seconds