Poster presented by Michael Creutz
Topic: Algorithms and Machines
Message Passing on the QCDSP Supercomputer
Abstract: The massively parallel QCDSP machines were designed expressly for lattice gauge calculations. For future planning it is crucial to know how this architecture adapts to other computationally intensive tasks. Partly with this in mind, and partly with a personal desire to understand the functioning of the machine, I have developed a simple message passing scheme for the straightforward manipulation of general data types. My goal is a small number of generic functions for manipulation of a large data set spread over the entire machine. I have explicitly avoided any use of assembly language, with the objective being ease of use and adaptability. I illustrate this flexibility with three radically different test applications: a fast Fourier transform, generic arbitrary dimension SU(N) pure lattice gauge theory, and the manipulation of Fermionic Fock states through a distributed hash table. These routines compile and run either on QCDSP or a standard Unix workstation.