Publications (4)0 Total impact
Conference Proceeding: QCDOC: A 10 Teraflops Computer for Tightly-Coupled Calculations[show abstract] [hide abstract]
ABSTRACT: Numerical simulations of the strong nuclear force, known as quantum chromodynamics or QCD, have proven to be a demanding, forefront problem in high-performance computing. In this report, we describe a new computer, QCDOC (QCD On a Chip), designed for optimal price/performance in the study of QCD. QCDOC uses a six-dimensional, low-latency mesh network to connect processing nodes, each of which includes a single custom ASIC, designed by our collaboration and built by IBM, plus DDR SDRAM. Each node has a peak speed of 1Gigaflops and two 12,288node, 10+ Teraflops machines are to be completed in the fall of 2004. Currently, a 512 node machine is running, delivering efficiencies as high as 45% of peak on the conjugate gradient solvers that dominate our calculations and a 4096-node machine with a cost of $1.6M is under construction. This should give us a price/performance less than $1per sustained Megaflops.Supercomputing, 2004. Proceedings of the ACM/IEEE SC2004 Conference; 12/2004
Conference Proceeding: QCDOC: A 10 Teraflops Computer for Tightly-Coupled Calculations.Proceedings of the ACM/IEEE SC2004 Conference on High Performance Networking and Computing, 6-12 November 2004, Pittsburgh, PA, USA, CD-Rom; 01/2004
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ABSTRACT: The QCDSP and QCDOC computers are two generations of multithousand-node multidimensional mesh-based computers designed to study quantum chromodynamics (QCD), the theory of the strong nuclear force. QCDSP (QCD on digital signal processors), a four-dimensional mesh machine, was completed in 1998; in that year, it won the Gordon Bell Prize in the price/performance category. Two large installations—of 8,192 and 12,288 nodes, with a combined peak speed of one teraflops—have been in operation since. QCD-on-a-chip (QCDOC) utilizes a six-dimensional mesh and compute nodes fabricated with IBM system-on-a-chip technology. It offers a tenfold improvement in price/performance. Currently, 100-node versions are operating, and there are plans to build three 12,288-node, 10-teraflops machines. In this paper, we describe the architecture of both the QCDSP and QCDOC machines, the operating systems employed, the user software environment, and the performance of our application—lattice QCD.
Article: Massive domain wall fermions[show abstract] [hide abstract]
ABSTRACT: If the domain wall formulation is used to treat up, down and strange quarks in a calculation of weak matrix elements, the Glashow, Iliopoulos and Maiani (GIM) mechanism requires using the same method for the charmed quark. We describe the behavior of massive domain wall fermions (DWF) for both free and interacting theories.Nuclear Physics B - Proceedings Supplements.