Garbage Collection in Object Oriented Databases Optimization of Unreachable Objects Detection.

Myriam Lamolle, Marc Gonzalez, Thierry Millan, Pierre Bazex: Garbage Collection in Object Oriented Databases Optimization of Unreachable Objects Detection CSIT 2000 : 38-46


This article presents new garbage collection algorithms to improve memory management in Object Oriented Databases (OODB). A toward garbage collector has highlighted a lack in the way of optimisation about the detection and reallocation of free memory space. In the context of OODB, the essential idea is the detection of unreachable objects. We propose a solution based on the graph theory. In fact, we claim the main problem is the graph tracing to detect unreachable object or unreachable cycle. The cycle can be replaced by the large cell which has the same characteristics as a simple object. To begin the process of garbage collection, we use a determinist method to locate unreachable objects at the end of a transaction. Moreover, the garbage collector reclaims the memory space of unreachable objects. To implement these concepts, we use a reference counting and a strongly connected components table. Some examples supports the concept of our algorithms, in particular the special cases.

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Printed Edition

Heinz Schweppe and Yuri S. Kabalnov (Eds.): CSIT'2000, Proceedings of 2nd International Workshop on Computer Science and Information Technologies, September 18-23, 2000, Ufa, Russia. USATU Publishers & JurInfoR-MSU Publishing 2000, ISBN 5-86911-312-1

Electronic Edition