Towards Virtual Shared Memory for Non-cache-coherent Multicore Systems

Emerging heterogeneous architectures do not necessarily provide cache-coherent shared memory across all components of the system. Although there are good reasons for this architectural decision, it does provide programmers with a challenge. Several programming models and approaches are currently available, including explicit data movement for offloading computation to coprocessors, and treating coprocessors as distributed memory machines by using message passing. This paper examines the potential of distributed shared memory (DSM) for addressing this programming challenge. We discuss how our recently proposed DSM system and its memory consistency model maps to the heterogeneous node context, and present experimental results that highlight the advantages and challenges of this approach.