An Algorithm for Supporting Fault Tolerant Objects in Distributed Object Oriented Operating Systems

This paper presents a new algorithm for supporting fault tolerant objects in distributed object oriented systems. The fault tolerance provided by the algorithm is fully user transparent. The algorithm uses checkpointing and message logging scheme. However the novelty of this scheme is in identifying the checkpointing instances such that the checkpointing time will not aaect the regular response time for the object requests. It also results in storing the minimum amount of object state(object address space). A simple message logging scheme that pairs the logging of response message and the next request message reduces the message logging time by half on an average compared to other similar logging schemes. The scheme exploits the general features and concepts associated with the notion of the objects and object interactions to its advantage.