We propose a new design for an energy-efficient hardware transactional memory (HTM) system for power-aware embedded devices. Prior hardware transactional memory designs proposed a small, fully-associative transactional cache at the same level as the L1 cache. We propose an alternative design that unifies the transactional and L1 caches, and provides a small victim cache to reduce effects of capacity and conflict evictions. We evaluate our new HTM scheme on a variety of benchmarks, both in terms of energy and performance. We show that the victim cache scheme can provide up to a 4X improvement in energy-delay product, compared to a traditional HTM scheme that uses a separate transactional cache.
Cesare Ferri, Samantha Wood, Tali Moreshet, R. Iri