# Presentation: 254499

## Department of Energy High Performance Computing

- Optical Interconnect Workshop
- November 8, 1999
- George Seweryniak
- ESnet Program Manager
- DOE HQ (GTN)

## System Architecture Trends

- Architectures increasing:
- Processor performance
- Processors / node, nodes / System
- Faster interconnects

**# Processors / Nodes**

**#  Nodes / System**

**1999**

**2000**

**2001**

## DOE Challenges

**DOE Challenges**

**Subsurface Transport**

**Global**
**Systems**

**Many DOE Programs**
**Need Dramatic Advances**
**in Computing Capabilities**
**To Meet Their**
**Mission Goals**

**Health Effects, Bioremediation**

**Fusion Energy**

**Combustion**

**Materials**

**Notes:**
Computational simulation has long been a component of the research programs sponsored by the Office of Science.

## DOE Computing Challenges

- 0.1

- 1

- 10

- 100

- 1000

- 1998

- 2000

- 2002

**Teraflops**

- 2004

**Moore’s Law**
**“****business as usual”**

**Building on a long tradition of driving the supercomputer industry, DOE, *****via***** ASCI, is once again fostering dramatic advancements in scientific computing.**
**SSI will make these capabilities available to the broader scientific and engineering communities —at much reduced cost.**

**ASCI Curve**

- 1996

- 2006

**Notes:**
The fidelity with which it is possible to simulate natural and engineered systems is strongly dependent on the available computing power.  The past twenty years has seen a dramatic increase in computing power—a increase of over a factor of ???.  As a result, it has been possible to solve many of the fundamental mathematical equations of physics for “simple” systems on the computer (the methane molecule composed of one carbon atom and four hydrogen atoms is an example of a “simple” system).  However, computational descriptions of “complex” systems still must evoke a number of questionable approximation (a protein molecule with thousands of atoms arranged in an intricate, yet well designed pattern, is an example of a “complex” system).
The level of approximation required to model “complex” systems is now undergoing a change.  The computer industry is already producing massively parallel computer systems capable of 1 trillion arithmetic operations per second (teraflops) and and been put on a path to produce a computer capable of 100 teraflops by the year 2004.  For this, ASCI has requested that the computer industry use commodity-priced building blocks and assemble those components into systems with the needed computing power.  This approach means that the resulting computer systems will be easily replicated for other applications—and at substantially reduced cost, because ASCI is funding much of the needed development efforts.
A balanced set of investments in the development of mathematical models, scientific simulation software, a terascale computing environment, and terascale computers will result in major advances in our ability to model complex systems in the next 5-10 years. 

## DOE ASCI Challenge

## Scientific Simulation Initiative

- In FY2000 the U.S. Department of Energy requested funding to initiate the **Scientific Simulation Initiative**.  The SSI seeks to:
***“... ******revolutionize the way that the Department of Energy solves its most demanding, mission-critical problems by fully utilizing the power of advanced computational simulation.”***
*Ernest J. Moniz*
*Undersecretary of Energy*
*December 1997*

## Initial SSI Program

**Initial SSI Program**

**Global Systems**

**Combustion Systems**

**Basic Sciences**

**•****	****IC Engines**
**•****	****Gas Turbines**
**•****	****Boilers**
**•****	****Burners **

**Terascale Systems Software**

**Terascale Computing Infrastructure**

**•****	****Transport**
**•****	****Genomics**
**•****	****Materials**
**•****	****Fusion**
**•****	****QCD**
**•****	****Nuclear Theory**
**•****	****...**

**•****	****Atmosphere**
**•****	****Ocean**
**•****	****Land**
**•****	****Sea Ice**

## Terascale Computing Infrastructure

- A site to operate a leading-edge tera-scale (5-40-... tf) computer system
- A terascale computing infrastructure to enable full utilization of the lead-ing-edge capability
- Team with other agencies to extend computing capabilities to other sites.

**Ultrahigh-speed Networks**

- 10-... Gbits/sec backbone network
- 1-... Gbits/sec network to support major sites
- Team with IT2 agencies to extend networking capabilities to other sites

**Large-scale Computing Systems**

## Global Climate Computing

## Meteorological Models

- Finer grid resolution provides more detail
- Increase vertical and horizontal resolution
- Data collection can be a major problem
- Requires more computational power and storage
- Can add more physics to the model
- Need high speed interconnects for computation/storage

## Combustion Systems

**Combustion Systems**

- Advances in combustion systems simulation requires **fundamental advances** in a number of areas, including:

- Development and utilization of high-resolution models of combustion devices (engines, burners, *etc*.);
- Development of reduced chemical mechanisms for fuel oxidation and pollutant formation;
- Development of rigorous science-based descriptions of processes, such as turbulence-chemistry inter-actions, droplet evaporation, *etc*.; and
- Integration of these submodels into a high-fidelity model of the complete system;

*iso-octane*

*as well as in using terascale computer systems for the wide range of scientific applications (mechanical engineering, fluid dynamics, chemistry, materials science) involved in combustion.*

## Problem Ensembles

**Problem Ensembles**

## Technical Challenges

**Computers**
- Terascale computers are based on a **new architecture **—massively parallel arrays of multiprocessors
- require very fast / reliable interconnects
**Systems Software**
**Operating system software **does **not** provide all of the needed functionality—lack of vendor financial interest
**Applications systems software** is non-existent for the scale of problems of interest
**Simulation Software**
**Existing software** does **not** **exploit the power** of the new architecture
**Industry**
- Government / industry partnerships required to meet the challenges

## Can DOE Meet the Challenge?

- Because of its mission, DOE has long been a **lead agency** in **high performance** **computing**, **scientific simulation**, **computer science**, and **applied mathematics**
- DOE has a long and successful history of establishing and operating **world-class computing facilities** and **first-of-a-kind computer systems**—from the IBM Stretch in the 1960’s to the massively parallel computers of the 1990’s
- DOE has a long and successful history of **managing large, complex research projects**

## DOE Commitment

**DOE cannot meet its mission without Terascale computing and Terascale infrastructure**
**cannot solve it alone**
**need to work with industry**
**system level approach**

##  Optical Interconnects

- A light at the end of the tunnel???

**THE END**