Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Vision for OSC Computing and Computational Sciences Thomas Zacharia Associate Laboratory Director Computing and Computational Sciences Oak Ridge National Laboratory Earth Simulator Rapid Response Meeting May 15-16, 2002

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Charge from Dr. Orbach Review “... current state of the national computer vendor community relative to high performance computing” “... Vision for what realistically should be accomplished in the next five years within the Office of Science in high performance computing”

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Dr. Orbach’s Vision for OSC Computing Statement to ASCAC Committee, May 8, 2002 “… there is a centrality of computation in everything that we do” “… large scale computation is the future of every program in the Office of Science” “… we want to have our own computing program in non-defense computational science”

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY FY 03 Budget Request for OSC Computing Considerably Lower than Required to Meet Goals 0 100,000, ,000, ,000, ,000, ,000, ,000, ,000, ,000, ,000,000 DOE-SCNNSANSF Fiscal Year Budget Dollars

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY As Fraction of Total Budget, OSC is Half NNSA and NSF and Needs Significant Increase to Meet Goals DOE-SCNNSANSF Computing Budget / Total Budget (%)

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Earth Simulator has Heightened Urgency for Infrastructure Strategy for Scientific Computing Critical Steps: Invest in critical software with integrated science, and computer science development teams Deploy scientific computing hardware infrastructure in support of “large scale computation” –Cray, HP, IBM, SGI –IBM is the largest US installation Develop new initiative to support advanced architecture research Top 500 Supercomputers US has been #1 in 12 of 19 lists A concerted effort will be required to regain US leadership in high performance computing. The LINPACK benchmark generally overestimates the effectiveness of an architecture for applications such as climate by a substantial factor. Stability and reliability are also important system properties.

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Invest in Critical Software with Integrated Science and Computer Science Development Teams SciDAC: a Good Start Towards Scientific Computing Software Scientific Applications –Climate Simulation –Computational Chemistry –Fusion – 5 Topics –High Energy Nuclear Physics – 5 Topics Collaboratories –Four Projects Middleware & Network Research –Six Projects Computer Science –Scalable Systems Software –Common Component Architecture –Performance Science and Engineering –Scientific Data Management Applied Mathematics –PDE Linear/Nonlinear Solvers and Libraries –Structured Grids/AMR –Unstructured Grids Dave Bader, SciDAC PI Meeting, Jan 15, 2002, Washington DC

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Deploy Scientific Computing Hardware Infrastructure to Support “Large-Scale Computation” Provide most effective and efficient computing resources for a set of scientific applications Serve as focal point for scientific research community as it adapts to new computing technologies Provide organizational framework needed for multidisciplinary activities –Addressing software challenges requires strong, long term collaborations among disciplinary computational scientists, computer scientists, and applied mathematicians Provide organizational framework needed for development of community codes –Implementing many scientific codes requires wide range of disciplinary expertise Organizational needs will continue to grow as computers advance to petaflops scale Dave Bader, SciDAC PI Meeting, Jan. 15, 2002, Washington, DC

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Earth Simulator has Widened Gap with DOE Scientific Computing Hardware Infrastructure  Top left: comparison between ES and SC resources – highlights widening gap between SC capabilities and others  Top right: comparison between ES and US resources of comparable peak performance – highlights architectural difference and need for new initiative to close the gap  Right: comparison between ES and US resources of comparable cost 1,000 3,000 5,000 7,000 Earth SimulatorSEABORGCHEETAH Simulations years/day Widening Gap 1,000 3,000 5,000 7,000 Earth SimulatorPOWER4 H+ (40TFlops)Power5 (50 TFlops) Simulations years/day Technology Gap 0 2,000 4,000 6,000 8,000 10,000 Earth SimulatorPOWER4 H+ (3*40TFlops)Power5 (3*50 TFlops) Simulations years/day

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Possible U.S. Response in the Near Term for Increased Computing Capacity 40 TFlops Peak 5120 Vector Processors 8 GFlops Processor 8 Processors per Node $500 M Procurement $50M/yr Maintenance Limited Software Investment to date Significant Ancillary Impact on Biology, Nanoscience, Astrophysics, HENP, Fusion 40 TFlops Peak 5120 Power5 Processors 8 GFlops Processor 64 Processors per Node $100 M Procurement $10M/yr Maintenance SciDAC Investment in Computational Science and related ISICs Significant Ancillary Impact on Biology, Nanoscience, Astrophysics, HENP, Fusion Earth Simulator US Alternative

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Best Performance of High Resolution Atmospheric Model Inter-node bandwidth (Mb/s) Performance of Hi-Resolution Atmospheric Model Earth Simulator (2560) AlphaES45 (2048) AlphaES40 (256 ) SP3 WHII (512) T3E (512) GFlops

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Year Dollars/GFlops C/L/D ASCI T3E Beowulfs COTS JPL QCDSP Columbia QCDOC Columbia/IBM Blue Gene/L ASCI Blue ASCI White ASCI Compaq Develop New Initiative to Support Advanced Architecture: BlueGene Offers Possible Option

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY QCDSP (600GF based on Texas Instruments DSP C31) – Gordon Bell Prize for Most Cost Effective Supercomputer in '98 – Columbia University Designed and Built – Optimized for Quantum Chromodynamics (QCD) – 12,000 50MF Processors – Commodity 2MB DRAM QCDOC (20TF based on IBM System-on-a-Chip) – Collaboration between Columbia University and IBM Research – Optimized for QCD – IBM 7SF Technology (ASIC Foundry Technology) – 20,000 1GF processors (nominal) – 4MB Embedded DRAM + External Commodity DDR/SDR SDRAM BlueGene L/D (180TF based on IBM System-on-a-Chip) – Designed by IBM Research in IBM CMOS 8SF Technology – 64, GF processors (nominal) – 4MB Embedded DRAM + External Commodity DDR SDRAM BlueGene Architecture is a (more) General Purpose Machine that builds on QCDOC

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Host System: – Diagnostics, booting, archive – Application dependent requirements System Organization (conceptual) File Server Array – ~ 500 RAID PC servers – Gb Ethernet and/or Infiniband – Application dependent requirements BlueGene/L Processing Nodes Nodes – Two major partitions – nodes production – Platform (256 TFlops peak) – nodes partitioned into code development platforms

Center for Computational Sciences O AK R IDGE N ATIONAL L ABORATORY U. S. D EPARTMENT OF E NERGY Summary Continue investment in critical software with integrated science, and computer science development teams Deploy scientific computing hardware infrastructure in support of “large scale computation” Develop new initiative to support advanced architecture research Develop a bold new facilities strategy for OSC computing Increase OSC computing budget to support outlined strategy Without sustained commitment to scientific computing, key computing and computational sciences capabilities, including personnel, will erode beyond recovery.