Semantic Conformance of Concurrency Control Protocols under Mixed Isolation Levels

Qiuhuan Xiong; Hengfeng Wei; Si Liu; Yuxing Chen; Jidong Ge

Semantic Conformance of Concurrency Control Protocols under Mixed Isolation Levels

Databases 2026-07-18 v1 Distributed, Parallel, and Cluster Computing

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.

Keywords

concurrency control isolation levels semantic conformance mixed isolation formal framework database systems

Cite

@article{arxiv.2607.16696,
  title  = {Semantic Conformance of Concurrency Control Protocols under Mixed Isolation Levels},
  author = {Qiuhuan Xiong and Hengfeng Wei and Si Liu and Yuxing Chen and Jidong Ge},
  journal= {arXiv preprint arXiv:2607.16696},
  year   = {2026}
}

Comments

Accepted to and to be presented at the 1st Symposium on Consistency Checking Principles (SCCP 2026)