DISC: A Domain-Interaction Based Programming Model with Support for Heterogeneous Execution

Several emerging trends are pointing to increasing heterogeneity among nodes and/or cores in HPC systems. Existing programming models, especially for distributed memory execution, typically have been designed to facilitate high performance on homogeneous systems. This paper describes a programming model and an associated runtime system we have developed to address the above need. The main concepts in the programming model are that of a domain and interactions between the domain elements. We explain how stencil computations, unstructured grid computations, and molecular dynamics applications can be expressed using these simple concepts. We show how interprocess communication can be handled efficiently at runtime just from the knowledge of domain interaction, for different types of applications. Subsequently, we develop techniques for the runtime system to automatically partition and re-partition the work among heterogeneous processors or nodes.