LiTM: A Lightweight Deterministic Software Transactional Memory System

Deterministic software transactional memory (STM) is a useful programming model for writing parallel codes, as it improves programmability (by supporting transactions) and debuggability (by supporting determinism). This paper presents LiTM, a new deterministic STM system that achieves both simplicity and efficiency at the same time. LiTM implements the deterministic reservations framework of Blelloch et al., but without requiring the programmer to understand the internals of the algorithm. Instead, the programmer writes the program in a transactional fashion and LiTM manages all data conflicts and automatically achieves deterministic parallelism. Our experiments on six benchmarks show that LiTM outperforms the state-of-the-art framework Galois by up to 5.8× on a 40-core machine.