Semantic Conformance of Concurrency Control Protocols under Mixed Isolation Levels
DatabasesDistributed, Parallel, and Cluster Computing
Summary
The authors study how modern database systems use different rules, called isolation levels, to keep data safe while working fast. They notice it's not clear if the current methods really follow these rules correctly when mixing several isolation levels in one system. To solve this, the authors create a formal framework named ourframework to check if databases behave properly under mixed isolation settings. They show their framework works by proving that two real methods stick to their intended rules when mixing two and three isolation levels.
Authors
Qiuhuan Xiong, Hengfeng Wei, Si Liu, Yuxing Chen, Jidong Ge
Abstract
Modern database systems widely support per-transaction isolation levels as a practical means of balancing consistency guarantees and performance. Yet, it remains largely unclear whether their concurrency control protocols correctly enforce the intended isolation guarantees under such mixed-isolation settings. In this paper, we address this semantic conformance question by developing \ourframework, a formal semantic framework for mixed isolation levels. We demonstrate its applicability by establishing the semantic conformance of two concurrency control protocols, one combining two isolation levels and the other three.