An Efficient Dynamic Analysis Tool for Checking Durable Linearizability

Abstract

Designing efficient and correct durable data structures is indispensable because Non-Volatile Memory (NVM) is positioned as a successor to DRAM due to its energy efficiency and reliability. The challenge with ensuring correctness for efficient durable data structures is that caches and registers are expected to remain volatile, and the explicit cache line flush and barrier instructions are expensive. As a result cache line flushes and barriers are used sparingly, leading to potential inconsistencies in the recoverable state of the data structure. Crash consistency tools are available to ensure recoverability to a consistent state, but these tools are not able to check correctness of data structure semantics. Furthermore, the formal logic proposed to verify correctness conditions such as durable linearizability involve labor intensive mechanical proofs using a theorem prover. In this paper, we present the first dynamic analysis tool that checks durable linearizability at runtime. Our proposed tool, VSV-D, uses a vector space analysis to achieve a worst-case O(n <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) time complexity. We extend the analysis to transactional correctness to enable VSV-D to check durable transactional data structures. Our experimental evaluation applies VSV-D to check the correctness of a large variety of durable data structures including log-free data structures, link-free data structures, Romulus, OneFile, PMDK, and PETRA.