QPACE: Quantum Chromodynamics Parallel Computing on the Cell Broadband Engine

The Quantum Chromodynamics Parallel Computing on the Cell Broadband Engine (QPACE) project is developing a massively parallel, scalable supercomputer for applications in lattice quantum chromodynamics (QCD). Specifically, the architecture is a 3D torus of identical processing nodes, based on the PowerXCell 8i processor. These nodes are tightly coupled by an application-optimized network processor that is based on a field-programmable gate array attached to the PowerXCell 8i. The authors have analyzed lattice QCD code performance on QPACE, carried out corresponding hardware benchmarks, and found that it offers suitable performance. They describe the QPACE architecture in detail, focusing on the challenges arising from the PowerXCell 8i's multicore nature and the use of an FPGA for the network processor.