Multidimensional Blocking in UPC

Abstract. Partitioned Global Address Space (PGAS) languages offer an attractive, high-productivity programming model for programming large-scale parallel machines. PGAS languages, such as Unified Parallel C (UPC), combine the simplicity of shared-memory programming with the efficiency of the messagepassing paradigm by allowing users control over the data layout. PGAS languages distinguish between private, shared-local, and shared-remote memory, with shared-remote accesses typically much more expensive than shared-local and private accesses, especially on distributed memory machines where sharedremote access implies communication over a network. In this paper we present a simple extension to the UPC language that allows the programmer to block shared arrays in multiple dimensions. We claim that this extension allows for better control of locality, and therefore performance, in the language. We describe an analysis that allows the compiler to distinguish between local shared array acce...

• Type: Conference
• Year: 2007
• Where: LCPC
• Authors: Christopher Barton, Calin Cascaval, George Almási, Rahul Garg, José Nelson Amaral, Montse Farreras
• Keywords: Array Accesses, Distributed And Parallel Computing, LCPC 2007, Local Shared Array, Shared-remote Accesses