August 13, 1998

Members:
Bill Joy, Co-Chair
Ken Kennedy, Co-Chair
Eric A. Benhamou
Vinton Cerf
Ching-chih ChenDavid Cooper
Steven D. Dorfman
David Dorman
Robert Ewald
David J. Farber
Sherrilynne S. Fuller
Hector Garcia-Molina
Susan L. Graham
James N. Gray
W. Daniel Hillis
John P. Miller
David C. Nagel
Raj Reddy
Edward H. Shortliffe
Larry Smarr
Joe F. Thompson
Leslie Vadasz
Andrew J. Viterbi
Steven J. Wallach
Irving Wladawsky-Berger

Honorable F. James Sensenbrenner, Jr.
Chair, House Science Committee
House of Representatives
2332 Rayburn House Office BuildingWashington, DC 20515-4909
Dear Chairman:
Thank you for your letter of April 12 and your interest in the activities of thePresident’s Information Technology Advisory Committee (PITAC). For the past year, theCommittee has been reviewing the High-End Computing and Computation (HECC)
component of the Computing, Information, and Communications (CIC) Research andDevelopment (R&D) program in the context of the entire Federal R&D investment in
information technology. Although the PITAC is concerned that changes in the structureof both corporate and government support are putting US leadership in high-end
computing at risk, we see this as only one aspect of a larger problem—the erosion ofsupport for long-term fundamental research in information technology. In the past, thiskind of research has provided the foundation for dramatic growth in the computing andcommunications industries, helped address problems of national importance, andcontributed to the education of an entire generation of information technology
professionals. If the nation is to continue the rapid pace of advances experienced over thepast decade, we must reverse the drift away from fundamental research.
Before exploring this issue in more detail, let us respond to the specific questions
raised in your letter:(i) [Are] the overall level of resources for the HECC component [of the CIC
R&D program] adequate and are they allocated appropriately?
Broadly speaking, there are two components to the HECC program, funding for
fundamental and applied research in high-end computing systems and software andinfrastructure to support high-end computation by the national community of scientists
and engineers. In our view, neither of these components is receiving adequate resources.
One of the original goals of the Federal High Performance Computing andCommunications (HPCC) Initiative, the predecessor to CIC R&D, was to extend U.S.
technological leadership in high performance computing and communications. Overtime, many participants in that program came to believe that the way to maintainleadership was to effect a paradigm shift from vector supercomputers to scalable parallel
computers, sometimes called massively parallel processors (MPPs). Since scalable
parallel processing could build on commodity technologies, it could ride the technology

c/o National Coordination Office for Computing, Information, and Communications
4201 Wilson Boulevard • Suite 690 • Arlington, VA 22230(703) 306-4722

Honorable F. James Sensenbrenner, Jr
Page 2
August 13, 1998
curve to achieve enormous processing power. Furthermore, if applications were written to efficiently
exploit parallelism, performance would smoothly scale from desktop to supercomputer.
For this goal to be realized, however, there would have to be major shifts in the way these machines
were programmed to make effective use of the available parallelism. Furthermore, there would need to
be innovations in hardware and software to provide adequate performance of data movement between
memory and the processors, and finally there would need to be a new generation of programming tools
to make it easier to reprogram applications for scalable machines. To address these needs, the program
included a sizeable component of fundamental and applied research support. Unfortunately, the level ofresearch support fell short of what was needed because (1) the problem proved to be much harder thanoriginally thought, and (2) as agency budgets became tight, funds were shifted from long-term research
to short-term development efforts so some applications would be available on time. The result is whatmight be called a “usability gap” for these machines. Although there is every reason to believe that thisgap can be bridged, increased investments in research and development will be needed to do so.
The usability gap also affects the availability of high-end computing cycles to the civilian sciencecommunity. When NSF restructured its supercomputer centers program, a major component wasfocused on enabling the technologies needed to make the transition to scalable parallel machines.
However, this change was made without a corresponding increase in the budget, leaving fewer dollars topurchase increasingly expensive high-end systems. As a result, compared to the National laboratories
and university centers in other countries, NSF center users have lost ground in terms of relative high end
resources available, which threatens the nation’s leadership in computational science and engineering.
Both of these areas need to be addressed if we are to continue the rapid progress in the solution ofimportant societal and scientific problems through high-end computation. The Committee recommends
that the Federal government recommit itself to the support of high-end computing through research on
new computing architectures, technologies, and software that can overcome the limitations of current
supercomputer designs. In addition, the Federal government should increase funding for the acquisitionof the powerful high-end computing systems needed by the nation’s science and engineeringcommunity, both within and outside the government.
(ii) [Is] the HECC component coordinated effectively with other high performance computing
activities of Federal mission agencies?
To be truly effective, coordination must take place both within the HECC program and between
HECC and other federal programs involving high-end computing, such as DOE’s ASCI program.
Within HECC, coordinating HECC-designated programs works well. The coordination process,however, has only a limited ability to manage the programs in ways that would lead to greater
government-wide efficiencies or to consider national benefits that transcend the specific needs ofcontributing agencies. Furthermore, since a substantial fraction of the HECC budget lies in mission
agencies, resources tend to be refocused on mission priorities over time, contributing to the drift towardHonorable F. James Sensenbrenner, JrPage 3
August 13, 1998
short-term applied research. To remedy this weakness, our report recommends that an agency
committed to fundamental research be designated as a lead for coordinating information technology
research including HECC, with the mission to ensure that federal IT research is well directed and withthe flexibility and authority to carry out that mission.
With regard to programs outside of HECC, we are particularly concerned about the lack ofcoordination between HECC and the large computer investments (both hardware and software) in theDepartments of Energy (ASCI) and Defense (HPC Modernization). To address this problem, these andother similar agency programs – current or under development, such as DOE’s Strategic Simulation
Program -- should be coordinated with HECC by the same mechanisms currently used within HECC.
(iii) [Will] the overall Federal R&D investment in high performance computing ensure
U.S. leadership in computing technology?
To maintain our leadership in high performance computing technology, the United States must
effect a transition from technologies that have application exclusively at the high-end to strategies thatare more compatible with the commercial market. With the end of the cold war, the market for the mostpowerful supercomputers has shrunk to the point that it is no longer viable for a company to support
itself exclusively in that market. In the United States, the solution has been to build on commodity
technologies by using scalable parallel computation. However, there have been significant problems
with the transition to these machines. The usability gap, alluded to earlier, has slowed the translation ofmany applications to these systems. In addition, there is evidence that some applications will not
perform well on these systems until bottlenecks in the memory hierarchy are overcome by improvedhardware and software. The committee believes that it is imperative that we develop new,commercially viable computing technologies to help solve the nation's critical problems. However, wecannot move forward without overcoming the impediments to usability of these technologies. Thus, wemust recommit ourselves to a program of increased research and development on high performancecomputing architecture and software along lines similar to that proposed in the recent HECC draft
strategy. Such an increase will continue to pay benefits to our nation by making it possible to build
computers of the highest performance largely from inexpensive but powerful commodity technologies.
Over the past few years, there has been real erosion of Federal research and development
investments in information technology—HECC is only one example. Left uncorrected, this erosion
threatens the nation's leadership in computing and communications technology and the economic boom
it has fostered. The Brooks-Sutherland report, “Evolving the High Performance Computing andCommunications Initiative to Support the Nation's Information Infrastructure” (NRC 1995),
documented a clear relationship between investment in fundamental research in computer andcomputational science and commercial impact a decade later. Foundations for the current boom werelaid a decade or more ago by the investments from DARPA, NSF, and other government and industrialentities. The erosion of government research funding, coupled with reductions in long-term funding byindustry and a continuing drain of university faculty to industry, threaten to interrupt the stream ofgood ideas that have fueled the information economy and led to the solution of many crucial national
problems in the 1990's.

Honorable F. James Sensenbrenner, JrPage 4
August 13, 1998
To address this problem, the Committee recommends that funding for fundamental research ininformation technology increase dramatically over the next several years. A portion of that increase
should help reinvigorate research in high-end computing, including architecture, software, andapplications. In addition, the nation's non-defense high-end computational infrastructure should be
brought back up to levels competitive with defense computing and with scientific computing facilities inother nations, notably Japan and Europe. However, the investment in computational infrastructure
should be viewed as an investment in instrumentation for science and engineering as well as aninvestment in computing. In particular, it must be carefully balanced against the goal of increasing
fundamental research support in all areas of information technology.
Thank you once again for your interest in our activities. The comments in this letter are excerpted
and adapted from our Interim Report to the President, a copy of which is attached. Please do nothesitate to contact either of us or any member of the Committee if you wish further information orclarification.

Respectfully,_____________
Bill Joy
Co-Chairman_____________Ken Kennedy
Co-ChairmanPresident’s Information Technology Advisory Committee
Attachment
cc: Honorable George E. Brown, Jr.