chapter  7
On Preparing the Super Instruction Architecture and Aces4 for Future Computer Systems
ByJason Byrd, Rodney Bartlett, Beverly A. Sanders
Pages 14

Blocks are the object of interest rather than individual array elements and a key aspect of the Super Instruction Architecture (SIA) is that algorithms are expressed in terms of operations on blocks, not individual floating point numbers. The SIA/Aces4 programming model shares some aspects of Global Arrays (GAs), but is based on the abstraction of blocked arrays rather than GAs. The super instructions are compiled into a library that is linked with the Aces4 executable. To fully exploit an exascale computer, super instructions will need to utilize fine-grained parallelism. An important goal of a software platform such as SIA/Aces4 is to make it easier for domain scientists to develop correct, performant code. To a large extent, this is accomplished by isolating the parts of the code that perform communication and asynchronous operations in the runtime system. The molecular-cluster perturbation theory is a linearly scaling novel computational approach to computing electronic properties of extremely large liquids and crystals.