The Hierarchically Tiled Arrays programming approach

In this paper, we show our initial experience with a class of objects, called Hierarchically Tiled Arrays (HTAs), that encapsulate parallelism. HTAs allow the construction of single-threaded parallel programs where a master process distributes tasks to be executed by a collection of servers holding the components (tiles) of the HTAs. The tiled and recursive nature of HTAs facilitates the adaptation of the programs that use them to varying machine configurations, and eases the mapping of data and tasks to parallel computers with a hierarchical organization. We have implemented HTAs as a MATLAB™ toolbox, overloading conventional operators and array functions such that HTA operations appear to the programmer as extensions of MATLAB™. Our experiments show that the resulting environment is ideal for the prototyping of parallel algorithms and greatly improves the ease of development of parallel programs while providing reasonable performance.