Managing Update Conflicts in Bayou, a Weakly Connected Replicated Storage System

摘要

Bayou is a replicated weakly consistent storage system designed for a mobilecomputing environment that includes portable machines with less than ideal network connectivity. To maximize availability, users can read and write any accessible relica. Bayou's design has focused on supporting application-specific mechanisms to detect and resolve the update conflicts that naturally arise in such a system, ensuring that replicas move towards eventual consistency, and defining a protocol by which the resolution of update conflicts stabilizes. It includes novel methods for conflict detection, called dependency checks, and per-write conflict resolution based on client-provided merge procedures. This paper presents the motivation for and design of these mechanisms and describes the experiences gained with an initial implementation of the system. (Copyright (c) Association for Computing Machinery 1995.)