Hybrid Atomicity for Nested Transactions

Abstract

This paper defines the notion of hybrid atomicity for nested transaction systems, and presents and verifies an algorithm providing this property. Hybrid atomicity is a modular property; it allows the correctness of a system to be deduced from the fact each object is implemented to have the property. It allows more concurrency than dynamic atomicity, by assigning timestamps to transaction at commit. The Avalon system provides exactly this facility.