ACIA, not ACID: Conditions, Properties and Challenges

TL;DR

This paper proposes replacing the traditional ACID model with ACIA, emphasizing high availability over durability for transaction support in online applications, reflecting evolving data management conditions.

Contribution

It introduces the ACIA model as a new standard, highlighting the shift from durability to high availability and discussing its implications for transaction support and research challenges.

Findings

High availability is often stronger than durability.

ACIA supports more diverse application requirements.

New research challenges arise from ACIA adoption.

Abstract

Although ACID is the previous golden rule for transaction support, durability is now not a basic requirement for data storage. Rather, high availability is becoming the first-class property required by online applications. We show that high availability of data is almost surely a stronger property than durability. We thus propose ACIA (Atomicity, Consistency, Isolation, Availability) as the new standard for transaction support. Essentially, the shift from ACID to ACIA is due to the change of assumed conditions for data management. Four major condition changes exist. With ACIA transactions, more diverse requirements can be flexibly supported for applications through the specification of consistency levels, isolation levels and fault tolerance levels. Clarifying the ACIA properties enables the exploitation of techniques used for ACID transactions, as well as bringing about new challenges for research.