TagTM - accelerating STMs with hardware tags for fast meta-data access

In this paper we introduce TagTM, a Software Transactional Memory (STM) system augmented with a new hardware mechanism that we call GTags. GTags are new hardware cache coherent tags that are used for fast meta-data access. TagTM uses GTags to reduce the cost associated with accesses to the transactional data and corresponding metadata. For the evaluation of TagTM, we use the STAMP TM benchmark suite. In the average case TagTM provides a speedup of 7-15% (across all STAMP applications), and in the best case shows up to 52% speedup of committed transaction execution time (for SSCA2 application).