TSXProf: Profiling Hardware Transactions

The availability of commercial hardware transactionalmemory (TM) systems has not yet been met with a rise in the numberof large-scale programs that use memory transactions explicitly. Asignificant impediment to the use of TM is the lack of tool support, specifically profilers that can identify and explain performance anomalies. In this paper, we introduce an end-to-end system that enables lowoverheadperformance profiling of large-scale transactional programs. We present algorithms and an implementation for Intel´s Haswellprocessors. With our system, it is possible to record a transactionalprogram´s execution with minimal overhead, and then replay it withina custom profiling tool to identify causes of contention and aborts, down to the granularity of individual memory accesses. Evaluationshows that our algorithms have low overhead, and our tools enableprogrammers to effectively explain performance anomalies.