FASTM: A Log-based Hardware Transactional Memory with Fast Abort Recovery

Abstract--Version management, one of the key design dimensions of Hardware Transactional Memory (HTM) systems, defines where and how transactional modifications are stored. Current HTM systems use either eager or lazy version management. Eager systems that keep new values in-place while they hold old values in a software log, suffer long delays when aborts are frequent because the pre-transactional state is recovered by software. Lazy systems that buffer new values in specialized hardware offer complex and inefficient solutions to handle hardware overflows, which are common in applications with coarse-grain transactions. In this paper, we present FASTM, an eager log-based HTM that takes advantage of the processor's cache hierarchy to provide fast abort recovery. FASTM uses a novel coherence protocol to buffer the transactional modifications in the first level cache and to keep the non-speculative values in the higher levels of the memory hierarchy. This mechanism allows fast abort...

• Type: Journal
• Year: 2009
• Where: IEEEPACT
• Authors: Marc Lupon, Grigorios Magklis, Antonio González
• Keywords: Abort Recovery, Cache, Distributed And Parallel Computing, HTM Systems, IEEEPACT 2009