phy.ornl/tsi/

1. TeraScale Supernova Initiative: A Networker’s Challenge http://www.phy.ornl.gov/tsi/ Explosions of Massive Stars • Relevance: • Element Production • Cosmic Laboratories • Driving Application • 11 Institution, 21 Investigator, 34 Person, Interdisciplinary Effort • ascertain the core collapse supernova mechanism(s) • understand supernova phenomenology • e.g.: (1) element synthesis, (2) neutrino, gravitational wave, and gamma ray signatures • provide theoretical foundation in support of OS experimental facilities (RHIC, SNO, RIA, NUSEL) • develop enabling technologies of relevance to many applications • e.g. 3D, multifrequency, precision radiation transport • serve as testbed for development and integration of technologies in simulation “pipeline” • e.g. data management, networking, data analysis, and visualization With ISIC and other collaborators: 77 people from 24 institutions involved.

2. Core Collapse Paradigm

3. Anatomy of a Supernova Need Boltzmann Solution • Need Angular Distribution • Need Spectrum • Need Neutrino Distribution • Fluid Instabilities • Rotation • Magnetic Fields Need these to few percent accuracy! 6D RMHD Problem!

4. Equations We Solve Dominant Computation: Nonlinear, integro-partial differential equations for the radiation distribution functions. Spherical Symmetry Axisymmetry No Symmetry Example: Boltzmann transport equation for spherical symmetry.

5. Data Management • 3D Hydrodynamics Run • 5 Variables (Density, Entropy, Three Fluid Velocities) • 1024 X 1024 X 1024 Cartesian Grid • 1000 Time Steps 43 Terabyte Dataset “The flea on the tail on the dog…” Multidimensional Neutrino Data 13 Petabyte Dataset ~3 Petabyte Dataset ...in weeks to months on a PF platform.

6. Networking Bulk Data Transfer Needs Needs for Collaborative Visualization Raw Bandwidth Needs • Need end-to-end dedicated paths/bandwidth, • on demand. • Interactive visualization. • Real-time collaboration. • Need protocols that provide this capability. • None exist that will give 10 Gbps throughputs • and stable control. • Work with Nagi Rao (ORNL). What about the radiation field data? @ 3 PB!

7. Addressing Bulk Data Transfer Needs: • Logistical Networking • Light Weight • Low Level • Deployable … Solution • New Paradigm • Integrate storage and networking. • Multi-source, multi-stream. • Data transfer rates 200-300 Mbps • using TCP/IP! • Limit set by ORNL firewall. • Greater rates expected • outside firewall, • other protocols (e.g., Sabul). • Direct impact on TSI’s ability to • do work! Atchley, Beck, and Moore (2003)

8. Summary • Without putting in place the needed computational science infrastructure, • our science will simply be inaccessible in the future. • Significant progress has been made in the areas of • linear solvers, • performance analysis and optimization, • data management and analysis, • networking, • and visualization. • In particular, Logistical Networking has provided an easily deployable • solution to our current bulk data transfer needs and has had a significant • impact on TSI’s current ability to do science. • TSI’s future data management and networking needs are daunting. TSI will • generate hundreds of TeraBytes of simulation data per simulation within the • next two years. What then? • Meeting these needs will require every new idea. Investment now in networking • technologies will allow us to meet these needs.