Ordering-Based Semantics for Software Transactional Memory

It has been widely suggested that memory transactions should behave as if they acquired and released a single global lock. Unfortunately, this behavior can be expensive to achieve, particularly when-as in the natural publication/privatization idiom--the same data are accessed both transactionally and nontransactionally. To avoid overhead, we propose selective strict serializability (SSS) semantics, in which transactions have a global total order, but nontransactional accesses are globally ordered only with respect to explicitly marked transactions. Our definition of SSS formally characterizes the permissible behaviors of an STM system without recourse to locks. If all transactions are marked, then SSS, singlelock semantics, and database-style strict serializability are equivalent. We evaluate several SSS implementations in the context of a TL2-like STM system. We also evaluate a weaker model, selective flow serializability (SFS), which is similar in motivation to the asymmetric lock a...

• Type: Conference
• Year: 2008
• Where: OPODIS
• Authors: Michael F. Spear, Luke Dalessandro, Virendra J. Marathe, Michael L. Scott
• Keywords: Distributed And Parallel Computing, OPODIS 2008, Selective Strict Serializability, Single Global Lock, Strict Serializability