Design and implementation of GORDION, an object base management system

An experimental object base management system called Gordion is presented. Gordion is a server which provides permanence and sharing of objects for workstations within an object-oriented environment. Among the unique aspects of Gordion are: its ability to communicate with multiple languages, introduction of new concurrency control primitives, ability to manipulate objects of arbitrary size, and object sharing across the languages through a base set of classes. The system is currently interfaced to two languages, BiggerTalk and Zetalisp Flavors. Beside its language interface, Gordion has an interface for the system administrator, and an interface for debugging. Major functional components of the system are: concurrency control, storage, history and inquiry, and maintenance. Concurrent access to objects is regulated by four types of locks, and transactions encapsulate units of work for the system. The storage system uses a hashing scheme and Unix™ files to store objects. A discussion of the future prospects for Gordion concludes the paper.