Persistent HyTM via Fast Path Fine-Grained Locking

TL;DR

This paper introduces persistent hybrid transactional memory (HyTM) techniques that leverage HTM fast paths for lock acquisition to ensure durability and linearizability, improving performance in read-dominant workloads.

Contribution

It presents novel persistent HyTM designs that use HTM primarily for lock management, addressing challenges in combining HTM with non-volatile memory for durability.

Findings

Achieves durable linearizable transactions with improved performance.

Outperforms state-of-the-art persistent STMs and HyTMs in read-dominant workloads.

Demonstrates the impact of progress guarantees on performance.

Abstract

Utilizing hardware transactional memory (HTM) in conjunction with non-volatile memory (NVM) to achieve persistence is quite difficult and somewhat awkward due to the fact that the primitives utilized to write data to NVM will abort HTM transactions. We present several persistent hybrid transactional memory (HyTM) that, perhaps counterintuitively, utilize an HTM fast path primarily to read or acquire fine-grained locks which protect data items. Our implementations guarantee durable linearizable transactions and the STM path satisfies either weak progressiveness or strong progressiveness. We discuss the design choices related to the differing progress guarantees and we examine how these design choices impact performance. We evaluate our persistent HyTM implementations using various microbenchmarks. Our implementations achieve improved performance especially for read dominant workloads compared to state of the art persistent STMs and persistent HyTMs despite the challenges and apparent awkwardness of using current implementation HTM to achieve persistence.