The Delta-4 extra performance architecture (XPA)

Abstract

The design of an extra performance architecture for Delta-4, which explicitly supports the requirements of real-time systems with respect to throughput and response, is presented. The Delta-4 approach to fault tolerance is based on the replication of software components on distinct host computers using a range of different replication strategies. The problems of replicate divergence are discussed, and a solution based on message selection and preemption synchronization messages is proposed. A description of the ongoing implementation of such a system within the overall Delta-4 framework is included.<>