Design and Implementation of K42's Dynamic Clustered Object Switching Mechanism Design and Implementation of K42's Dynamic Clustered Object Switching Mechanism

Design and Implementation of K42's Dynamic Clustered Object Switching Mechanism Kevin Hui Master of Science Graduate Department of Computer Science University of Toronto 2000 Recent research e orts have investigated customizable operating systems, where the implementation of operating system services can be chosen to meet an application's performance or functionality requirements. This dissertation investigates the potential benets of allowing the customization to be changed, on-they, while the service is in use. By using a prototype implementation of the dynamic object switching layer in the K42 operating system, we explore the costs and bene ts associated with dynamic customization. As an example, we showed how K42 can switch a (perle) page cache from a centralized implementation to one distributed across the processors of a multiprocessor in order to adapt to changing access patterns. The ability to customize on-they allows the implementation of a service to match the instantaneous demands on the service, avoiding the need to comprise a complex, catch-all implementation. It also facilitates live-swapping of system components in mission-critical systems where downtime is undesirable. ii Acknowledgements I would like to thank all the members of the K42 research group at the IBM T. J. Watson Research Center, who have been excellent sources of ideas and answers: Mark Auslander, David Edelsohn, Orran Krieger, Craig MacDonald, Bryan Rosenburg, Rick Simpson, Robert Wisniewski, and Jimi Xenidis. I would especially like to thank Robert Wisniewski, who acted as my mentor during my visit at the IBM lab, for his helpful supervision and invaluable advice. I would also like to thank K42 Toronto researchers Ben Gamsa and Jonathan Appavoo for their K42/Tornado knowledge and other advice in general. Last but certainly not least, I thank my thesis advisor, Professor Michael Stumm, for giving me the opportunity to work on K42 at the IBM lab, and for all the guidance he provided. iii