Unifying Thread-Level Speculation and Transactional Memory

Abstract. The motivation of this work is to ask whether Transactional Memory (TM) and Thread-Level Speculation (TLS), two prominent con-currency paradigms usually considered separately, can be combined into a hybrid approach that extracts untapped parallelism and speed-up from common programs. We show that the answer is positive by describing an algorithm, called TLSTM, that leverages an existing TM with TLS capabilities. We also show that our approach is able to achieve up to a 48 % increase in throughput over the base TM, on read dominated workloads of long transactions in a multi-threaded application, among other results.