Atomicity Policies using Design Patterns

This paper describes three object-oriented design patterns local serialization, global serialization and recovery and their integration to support atomic objects. The paper emphasizes the policies each pattern offers and the heterogeneity of policies resulting from their integration. The policies supported by the patterns include: pessimistic and optimistic serialization; static, dynamic and hybrid global serialization policies; redo, undo, copy and compensating recoverypolicies. The patterns emphasize decoupling of solutions to offer flexible, adaptable and extensible compositions. The patterns allow: decoupling the functional part from the concurrent part; decoupling concurrency control from concurrency generation; decoupling object-specific information from generic algorithms of concurrency control and recovery; decoupling global serialization policies from local serialization policies; and decoupling concurrency control from recovery.