Closing the Window of Vulnerability in Multiphase memory transaction: The alewife transaction store

Multiprocessor architects have begun to explore several mechanisms such as prefetching, context-switching and software-assisted dynamic cache-coherence, which transform single-phase memory transactions in conventional memory systems into multi-phase operations. Multiphase operations introduce a window of vulnerability in which data can be invalidated before it is used. Losing data due to invalidations introduces damaging livelock situations. This thesis discusses the origins of the window of vulnerability and proposes an architectural framework that closes it. The framework employs fully-associative transaction-buffers and an algorithm called thrashlock. It has been implemented as one facet of the Alewife machine, a large-scale cache-coherent multiprocessor.