Transaction processing core for accelerating software transactional memory

Submitted for review to MICRO-40 conference the 9th of June 2007This paper introduces an advanced hardware based approach for accelerating Software Transactional Memory (STM). The proposed solution focuses on speeding up conflict detection that grows polynomially with the number of concurrently running transactions and shared to transaction-local address resolution, which is the most frequent STM operation. This is achieved by logic split in two hardware units: Transaction Processing Core and Transactional Memory Look-Aside Buffer. The Transaction Processing Core is a separate hardware unit which does eager conflict detection and address resolution by indexing transactional objects based on their virtual addresses. The Transactional Memory Look-aside Buffer is a per-processor extension that caches the translated addresses by the Transaction Processing Core. The effect of its function is a reduced bus traffic and the time spent for communication between the CPUs and the Transaction Processing Core. Compared with other existing solutions, our approach mainly differs in proposing an implementation that is not based on the processor cache but a separate on-chip core, uses virtual addresses, does not require application modification and is further enhanced by Transactional Memory Look-Aside Buffer. Our experiments confirm the potential of the Transaction Processing Core to dramatically speed up STM systems