Report of the Review Committee

30 November 2007

Review of the Center for Computational Sciences,
University of Tsukuba, 2007
Summary of Conclusions and Recommendations
1. The Review Committee was impressed by the achievements of the Center for
Computational Sciences (CCS), its interdisciplinary culture, its leadership and its
vision for the future. The Committee believes that the collective expertise in theCenter and the research environment it has built are unique worldwide. In continuing
the work of the previous Center for Computational Physics, the CCS has establishedover a period of 15 years a highly successful collaboration between computerscientists and physicists that has built a series of world-class computers and usedthem to produce results at the forefront of computational physics. This is an example
to other areas of computational science and collaborative working has been wellintegrated into the culture of the Center. The promotion of this interdisciplinary
approach to computational science research should remain the core objective of CCS.
In order to repeat this success, it is necessary to identify projects in whichapplications and computer scientists have shared common goals. The CCS should
maintain a portfolio of exciting research projects at the forefront of computational andcomputer science, a talented faculty engaged in this research, and an environment inwhich shared goals can emerge and be nurtured. It will need continually to seek
mechanisms and incentives for participating in interdisciplinary projects. The Review
Committee commends the CCS to the University and recommends that the University
acknowledges its strategic value, supports the execution of its mission, andencourages the wider academic community to engage with its activities.
2. The reorganisation of the Center in 2004 has been successfully accomplished and the
Review Committee congratulates the Center on expanding its faculty and establishing
new research groups with a breadth of applications that are at the forefronts of theirrespective fields and of growing importance in the 21st century. Some of these newgroups are sub-critical in size, however, and they will need to build strong
collaborative links outside the Center, or be targeted for new hires. The Review
Committee also strongly supports the Center’s vision for computational science andthe collaborative culture that it is fostering between these researchers which was
clearly reflected in all the presentations to the Committee.
3. The Review Committee considers the CCS’s research in lattice QCD to be worldleading and that the International Lattice Data Grid/Japan Lattice Data Grid
(ILDG/JLDG) project is establishing an important global infrastructure. The Divisionof High Performance Computing (HPC) Systems is also world-leading, being one of
the few groups in the world that are successfully building HPC systems in an
academic setting. They are highly regarded, productive and innovative. The researchin astrophysics is diverse, some of it at the forefront, and has the potential with
FIRST to make significant breakthroughs in new application areas. Thus, theComputational Astrophysics Group has the potential to become world-leading if it
1

Report of the Review Committee

30 November 2007

can achieve greater coherence around its areas of strength. The condensed matter
research focuses on fundamental aspects of future device applications and is
excellent. The application of time-dependent density functional theory to both
molecular and nuclear physics is a unique combination, and the collaboration between
the Computational Condensed Matter Science, Quantum Many-Body Systems andComputational Life Science Groups could soon make the CCS a world-leader in thisnew approach. The Computational Media Group is also excellent, verging on worldclass, but its link to HPC is a future opportunity. The Biological Science Group is
excellent, but it is sub-critical in size, and synergy with HPC will also take time togenerate fruitful research. The Global Environmental Science Group is producing
some excellent work and its focus on downscaling of climate change is appropriate,
but it is also sub-critical in size. The Computational Intelligence Group is also
excellent and its collaboration with the geo-scientists has created an important
opportunity to communicate climate science to the public.
4. The CCS should have an internationally competitive computing facility to support its
research projects so that it can focus appropriate computational resources to ensure
they have maximum impact in their fields. The Center’s strategy to take responsibility
for the University’s research-oriented supercomputing service will help it to maintaincontrol of appropriate systems and the planned “T2K” acquisition will achieve thisfor the next 3-4 years. Additionally, CCS should continue to develop new computing
technologies in the context of the most demanding applications needs and have thecapability to bring these technologies into use to make breakthroughs in specific areasof computational science. The development of novel architectures is high risk but
high reward, and although the funding required for any particular development cannot
be guaranteed, the Center’s successful track record in this area is a major strength
which is rare worldwide and should not be lost. There is a rapidly evolving range of
new technologies which might be deployed to make significant advances incomputational science and the Center is particularly well-positioned to evaluate andexploit these.
5. The CCS has too few technical staff both to support growing use of its computers by
its increased range of projects and to develop applications codes that scale efficiently
on petascale architectures which will be vital to their continued competitiveness. Thissituation will be aggravated as the Center becomes responsible for users of the
University’s supercomputer and for external projects which may not include CCS
research staff. However, this also creates the opportunity for the University to transfer
the required support staff, or the funding for them, to CCS along with responsibility
for its supercomputer service. CCS will need to introduce a more service-oriented
user support mechanism for this wider range of users, because the Center will risk its
excellent reputation if the service is poor, but it must be careful to ensure that thisservice activity does not dilute the Center’s research focus.
6. The expansion of the CCS’s graduate education activities to include a dual degree
programme in computational science is strongly endorsed by the Review Committee,
because it will help to build a strong computational science community within the2

Report of the Review Committee

30 November 2007

University and to train the next generation of computational scientists. The
Committee recognises that there may be challenges in defining a curriculum which is
attractive to both students and the wider faculty within the University. We encourage
the University leadership to support this initiative by the CCS.
7. The CCS’s interdisciplinary research focus, educational activities and pioneering of
new technologies should enable it to play a major role in supporting initiatives suchas the National Next Generation Supercomputer (“Petaflops”) Project. The Center
should seek strategic partnerships with national projects such as this, which exploit its
complementary expertise in developing new application areas in computational
science and its capabilities as an icebreaker for innovative algorithms, highperformance software and new hardware technologies.
8. The CCS should actively develop international collaborators for some future core
projects, recognising the trend towards multi-national petascale supercomputing
facilities and building on the success of ILDG. Today, the CCS has a highinternational profile. It should leverage this now to participate in a broader range ofinternational projects, so that it continues to be recognised as the center of excellence
for interdisciplinary computational science research in Japan.
9. The PACS-CS project was a successful and timely development to provide anappropriate computing resource to support the expanded range of projects in theCenter, bridging to the next University supercomputer. The Center’s systemdevelopment expertise created the opportunity to incorporate a more capable (hypercrossbar) interconnect than was available commercially at the time, and this has
already benefited applications on 256 and 512-node partitions. The benefit should beeven greater when the system is configured to run applications on up to 2048 nodes.
The CCS is now well-positioned to do breakthrough science in QCD and materials
science using this full capability.
10. The FIRST project is unique in the world and typifies the Center’s ability to use
applications needs to drive innovative computer architecture and systems research,which in turn delivers scientific results at the forefront of the applications field. This
has enabled the GRAPE technology to be deployed effectively for a wider range offrontier astrophysics applications. Specialised hardware will continue to play a vitalrole in specific fields. The expertise that CCS has acquired in embedding acceleratorsin general-purpose clusters will have wider applicability in the future and should be
the basis for follow-on projects.

Review Committee, its Operation and Objectives
11. The Review Committee comprised Professor Richard Kenway (University of
Edinburgh), Chair, Professor Yoshio Oyanagi (Kogakuin University), Vice-Chair,
Professor Masaru Kitsuregawa (University of Tokyo), Professor Michael Norman(University of California, San Diego), Professor Hervé Philippe (University of3

Report of the Review Committee

30 November 2007

Montreal), Professor Horst Simon (Lawrence Berkeley National Laboratory),
Professor Akimasa Sumi (University of Tokyo) and Professor Kiyoyuki Terakura(Japan Advanced Institute of Science and Technology).
12. The objective of the External Review was to evaluate the research activities of theCenter for Computational Sciences (CCS) in the context of its mission, since its
reorganisation in 2004 and at the midterm in its six-year plan. The Review was asked
to focus on the work of each research group and the three core projects, PACS-CS,
FIRST and ILDG/JLDG, with regard to both their achievements and the effectivenessof their interdisciplinary collaborations. The Committee ranked the research groups,
in terms of the originality and impact of their outputs, according to the following
categories: “world-leading” (amongst the five best groups in the world); “worldclass” (the best group in Japan and internationally recognised for consistently
producing excellent work, but falls short of the best in the world); “excellent”(amongst the five best groups in Japan, with international recognition for some work,
but lacking the consistency or impact of a world-class group). Finally, the Committee
was invited to comment on the future vision and strategies of the CCS.
13. The Review Committee visited the CCS from 30 Oct to 1 Nov 2007. It had available
three reports: “PART I, Overview of Center for Computational Sciences Summary of
Activities 2004-2007”, “PART II, Research Activities, Results, Collaborations andPlan 2004-2007” and “PART III, Vision and Strategies of Center for Computational
Sciences”. During the visit, the Committee received presentations from the Director,
Professor Mitsuhisa Sato, and former Director (now Executive Advisor to the
President of the University of Tsukuba), Professor Akira Ukawa, about the activitiesof the Center since 2004, from each of the research groups (Computational Particle
Physics, Computational Astrophysics, Computational Condensed Matter Science,
Computational Life Science, Quantum Many-Body Systems, Global Environmental
Science, Biological Science, Computational Intelligence, and Computational Media),from the Division of HPC Systems, and from the PACS-CS, FIRST and ILDG/JLDG
Projects. In addition, the members of the Committee divided into three subgroups tohear further presentations of research results in their own fields. Finally, Professor
Sato presented the future plan and strategies of the CCS. The Committee was able todiscuss with members of the CCS on a one-to-one basis and collectively with thesenior management. During the latter, it received responses to questions that hadarisen during the presentations. The Chair presented the Committee’s conclusions andrecommendations to a meeting of all the members of the Center at the end of theCommittee’s visit.

Research Activities
Division of Particle Physics and Astrophysics
14. Computational Particle Physics Group. This Group has played a defining role in all
major aspects of the Center since its conception. In particular, with the CP-PACS
Project, it successfully demonstrated how collaboration between applications and4

Report of the Review Committee

30 November 2007

computer scientists could achieve a world lead by a substantial margin and thereby
dominate the field for several years. This project produced a landmark result byfalsifying quenched QCD and now the Group is poised for another landmark
computation using PACS-CS to carry out the first simulation of lattice QCD at thephysical parameter values, removing all need for extrapolation except for thecontinuum limit. In parallel, the Group continues to produce results for a wide rangeof physical quantities from lattice QCD, some for the first time and many which arestate-of-the-art. The Group has retained coherence in its physics programme overmany years and has built an international reputation for excellence in the field whichis unsurpassed. In addition, the Group has been a driving force behind the ILDG and
JLDG, in the former case promoting international cooperation through its leadershipof the International Lattice Field Theory Network. New algorithms which aresubstantially faster than previous ones, the Group’s wealth of experience and theprospect of multi-hundred teraflops years of computing are now accelerating it
towards a period of unprecedented physics output. It should continue to be the jewel
in the Center’s research programme.
15. Computational Astrophysics Group. This Group, under the leadership of Professor
Masayuki Umemura, is large and diverse. The addition of two junior faculty in 2005
and 2007 represents a healthy investment in the future. The presence of 4 postdoctoral
associates, 15 graduate students and 4 undergraduates make it one of the largest
computational astrophysics groups in the world. With access to unique computational
resources (FIRST, PACS-CS), it has the potential also to be one of the best. A wide
variety of research applications in astrophysics and cosmology are being pursued,
some of them pioneering. Particularly notable are the algorithm development work,and the applications in radiation hydrodynamic simulations and advanced models ofmagnetically driven outflows. Not all of the research presented was of uniformly highquality, perhaps because it represented some exploratory forays into new topics andapplications by students. There is a danger, with so many codes and abundant
computer resources available, of dabbling in many areas. The Group could increase
its scientific impact and visibility by concentrating on a few leading problems anddeveloping a coordinated plan of attack, guided by observational data, much as theComputational Particle Physics Group has done. The Committee was happy to hear
about several projects that are closely guided by new observations, some of it fromJapanese observatories. The Committee endorses the Computational Astrophysics
Group’s future plans to heavily exploit the FIRST computer, to collaborate with theDivision of HPC Systems on the Multiple Architecture Seamless System (MASS),
and collaborate with the Division of Material and Life Sciences on ab initio
calculations of 3-body molecular hydrogen formation in connection with first starformation research. We advise caution on the Computational Observatory Project.
While the idea is sound, it represents a substantial effort to implement and maintain,
with unclear payoff at the present time. Any such effort should be coordinated with
the Theory Virtual Observatory Working Group of the International Virtual
Observatory Association (IVOA).

5

Report of the Review Committee

30 November 2007

Division of Materials and Life Sciences
16. Computational Condensed Matter Science Group. The research activities of thisGroup are well focused on fundamental studies of next generation device
technologies. In this context, the scientific level of their activity is quite high. In theiranalysis of problems for present and near future Si technology, the identification of
structural and electronic properties of divacancy in Si is a good example of the needfor large-scale electronic structure calculations. The actual calculation was performed
with their newly developed highly parallel real-space density functional theory(RSDFT) code. Another output of technological and scientific importance is their
new theory of Schottky barriers. Their search for new properties and phenomena in
the construction elements for future nano-scale device technologies has focused oncarbon nanotubes (CNT). Some examples are: the interaction between CNT anddifferent substrates, such as Si, Al and Ca; bias voltage dependence of nanocapacitors; and magnetic properties of edge states of CNT. The Group collaborates
with the Computational Life Science Group on the analysis of electronic and atomic
processes in biological systems. Actual calculations are mostly done using the
QM/MM method implemented in the CPMD package, originally developed byParrinello’s community. Professor Mauro Boero was originally a member ofParrinello’s group and is still contributing to the development of CPMD. The analysisof the proton diffusion mechanism in Cytochrome c Oxidase is a very important
contribution. The Group’s development of highly parallel computer codes for density
functional theory (DFT) based electronic structure calculations jointly with theDivision of HPC Systems is a very important example of collaboration between
computational science and computer science, and will promote highly parallel
computing within the Japanese community, which is crucial for the National Next
Generation Supercomputer Project. The planned attempt to run a 10,000 atom DFT
calculation on a 2048-node partition of PACS-CS would be a landmark in the field.
17. Computational Life Science Group. This Group studies the function of biologicalmolecules (protein and RNA) using simulations. Several different simulation
techniques are used and the most promising one is developed in collaboration with
the Condensed Matter Group. The use of DFT is new in Biology and the CCS is
therefore well placed to become a leader thanks to the unique interactions that exist
within the Center. Simulations are used to study a wide variety of molecules (e.g.
from ribozymes to cox). This large diversity of techniques and of applications is
potentially useful to tackle the difficult issue of biological function, but great careshould be taken to avoid over-dispersion that will hamper research and reduce its
international impact.
18. Quantum Many-Body Systems Group. In contrast to the Computational Condensed
Matter Science Group, this Group mostly treats excited states. Their targets are bothelectronic and nuclear systems. The central methods used are the time-dependent(TD) Schrödinger equation and time-dependent density functional theory (TD-DFT).
The dynamics of excited states is an important subject in materials science and also
biological science. This Group has been collaborating with the Computational
Condensed Matter Science Group and the Division of HPC Systems. The finite

6

Report of the Review Committee

30 November 2007

difference technique to solve the Kohn-Sham equation was first adopted for TD-DFT
in this Group. In future, collaboration with Computational Life Science Group will
also be fruitful. The Group’s work on excitations in both electronic and nuclear
systems using the same methodological framework (particularly for TD-DFT) is
particularly interesting. Materials under laser irradiation are studied using both TDDFT and the TD-Schrödinger equation. Both treat tunneling ionization and rescattering. The former approach can treat larger systems, while the latter may be moreaccurate. A new approach based on the TD-Schrödinger equation has been developed
to study the quantum dynamics of few-body reaction processes for nucleons, such as
anti-proton helium production. The TD-DFT method has been applied both toelectronic excitations in organic molecules and nuclear excitations in atomic nuclei.
From the study of optical response, useful information on the shape of molecules andnuclei can be obtained. Particularly for nuclear systems, the search for a moreaccurate functional in DFT is now in progress internationally. This Group iscontributing to the Universal Nuclear Energy Density Functional (UNEDF) project in
the framework of SciDAC in the USA. Based on quantum chemical calculations forclusters, fundamental electronic properties of high-Tc cuprates have been studied.
The importance of strong electron-phonon coupling was emphasized.

Division of Global Environment and Biological Sciences
19. Global Environmental Science Group. Atmospheric science was a good choice for the
first topic of the Global Environmental Science Group, because it has a long historyof numerical simulation using high-end computers. As meteorological data andprediction are widely used in society, the JMA/GPV data archive project jointly with
the Computational Intelligence Group targets an infrastructural development withwide impact, and is a nice collaboration between computer scientists and atmosphericscientists. The Group has started to develop NICAM (non-hydrostatic global
atmospheric model) for petaflops computer systems, and is going to emphasise thedown-scaling of global warming to focus on its regional effects. This area is relatively
weak in Japan and should be expanded. Considering the scale of the task, the existingGroup is very small. Collaboration with other groups, additional supporting staff andpostdoctoral fellows will be necessary if it is to be successful.
20. Biological Science Group. This Group, although small and recent, is very active, withseveral publications in high impact journals. It is interested in the evolution of
unicellular eukaryotes, especially in the inference of the global eukaryotic phylogeny.
A large part of the activity is devoted to data gathering (i.e., to isolate, describe andculture organisms, and finally obtain DNA sequences), which is of prime importanceto remain competitive. They are well aware of the difficulties of phylogenetic
inference and have initiated collaboration with computational researchers to address
one of them (separate model). The result, an MPI version of Tree-Puzzle, is also
efficient at avoiding the frequent problem of being trapped in local minima and willcertainly be used worldwide. This collaboration is quite promising, but would
strongly benefit from an additional professor to help bridge the gap between these
distant research fields.

7

Report of the Review Committee

30 November 2007

Division of High Performance Computing Systems
21. This Division is led by Professor Taisuke Boku. The Review Committee heard
several presentations about its projects, including: Scalable High-Performance andCluster Network (Boku); Grid-Data Farm, Gfarm, Distributed File System (Tatebe);
FFT and Classical Gram-Schmidt (Takahashi); and Power Aware Computing(Kohuta). The Division occupies a central role and is performing excellent research instrategic areas. There are two themes cutting across the projects: one is the focus on
applied projects that have an immediate impact on computational science elsewherein CCS; the other is energy efficient technologies. Both research directions are wellchosen and have tangible results.
22. The Gfarm project is addressing the challenges that we will face managing large
datasets in the near future, for example, the petascale data expected from the LHC at
CERN. It is a commodity-based distributed file system that can be mounted from allcluster nodes and clients, supports fault tolerance and avoids unnecessary duplication.
Gfarm is already integrated at CCS, for example, with FIRST. Gfarm has also
demonstrated outstanding performance and won an award at SC06, where a total of
52.0 GB/s was measured for parallel read. Gfarm is an open source development, and
CCS should be encouraged to continue developing it, since, with Lustre becoming a
potentially proprietary product, there is no capable open source alternative out there.
23. The work on FFTE is very impressive. FFTE is a package for complex, mixed-radix,
parallel FFTs that supports SSE2/SSE3 instructions, portability, and obtains highperformance. The work on Classical Gram-Schmidt (CGS) for the real-space DFT
application is a beautiful example of how advanced numerical algorithm work can be
integrated with large-scale application codes. This type of success is only possible in
an integrated environment such as CCS. By implementing CGS as an iterative
scheme with the “twice is mostly enough” Daniel iteration, and then re-writing theorthogonalization as level 3 BLAS with recursive blocking, the team got near
theoretical peak speed on a Xeon processor. This was a very impressive
accomplishment that was obtained by using clever numerical techniques that are notwidely known or appreciated. Professor Takahashi has done some very fine numerical
work here.
24. The second theme of the Division focuses on energy efficient technologies. There has
been very little work done in power efficient networking, and the research presented
on multi-link aggregation with RAID-like ideas is innovative and creative. Similarly,
using DVFS (dynamic voltage frequency scaling) for designing a power scaling
system on a cluster, and implementing energy aware optimization, is very clever.
CCS should continue to work in these areas. In particular, the work in energy
efficiency and computer architecture has the potential for far-reaching impact in years
to come.

Division of Computational Informatics
25. Computational Intelligence Group. This Group is developing tools for integrating
heterogeneous databases and various information sources, data mining to discover8

Report of the Review Committee

30 November 2007

knowledge and rules from massive data, and XML-related technologies to deal withvarious data on the Internet. It is one of the strongest database research groups inJapan. The Group is playing a substantial role, in collaboration with the Global
Environmental Science Group, to establish and maintain the GPV/JMA
meteorological archive and web site. This is well organized, with sophisticated XML
technologies, to integrate a number of data sources using meteorological ontology andis becoming very popular among the research community. The Group’s paper on the
integrated use of meteorological data was accepted by the IEEE e-Science
Conference. The collaboration between the two Groups is a good example of theinterdisciplinary work fostered by the CCS. The StreamSpinner stream processing
system that the Computational Intelligence Group is developing is a powerful tool for
integrating heterogeneous data sources, particularly event driven sensor systems. In
future, complex sensor stream mining is likely to be an interesting computationallyheavy application domain for the CCS, and an opportunity to cooperate more closelywith the Division of HPC Systems.
26. Computational Media Group. Professor Ohta’s Group aims to integrate sensing,
network, grid and visualisation technologies to augment the human senses. It has highinternational standing and a strong publication record. In addition, the Group has
implemented several real systems which show its excellent capabilities – especiallythe real-time 3D free viewpoint video system and the mixed reality see-through visionsystem are outstanding. Since the Group joined CCS rather recently, it has not yet
exploited the computational power available in CCS. However, its ambitious
challenge, ‘Real-World Computational Informatics’, to process vast amounts of datasensed from human society and the environment so that they can be readily
assimilated by humans will very likely create a new demand for huge computational
resources. The Division of HPC Systems could therefore make a substantial
contribution to this exciting research target newly defined by the Computational
Media Group and the project could become an important core component of the CCS
activities.

Major CCS Projects
PACS-CS
27. PACS-CS is a custom-designed HPC system for a few specific applications: QCD,
nano-material science, astrophysics, environment and biology. The selected target
applications required more bandwidth to memory and bisection bandwidth for theinterconnect than could be obtained with an entirely commodity cluster. Therefore,
following the very successful model of CP-PACS, the team under the direction ofProfessor Taisuke Boku built an MPP-like system based on commodity technologythat was better balanced for the above applications, which are characterized byrequiring nearest-neighbour and collective communications. They built a 3D hypercrossbar interconnect using commodity technology, such as L2 switches with 10 to 20
ports. The resulting 3D configuration is designed for up to 4096 nodes with 16 CPUs

9

Report of the Review Committee

30 November 2007

per dimension. The system is configured with 2GB memory per node and, physically,is built in 59 racks, using 550 kW of power.
28. The PACS-CS project was a successful and timely development to provide anappropriate computing resource to support the expanded range of projects in theCenter, bridging to the next University supercomputer. The CCS team under the
direction of Professor Boku did an excellent job in leveraging the existing expertiseand building a more capable technology than was commercially available at the time.
Thus, CCS is one of the few centers worldwide that has the expertise to build customdeveloped systems that can live up to the expectations of production science users.
The speed at which the PACS-CS system became available and the low rate of
failures and problems are quite remarkable for a custom-built system. PACS-CS has
already benefited applications on 256 and 512-node partitions. The benefit should beeven greater when the system is configured to run applications on up to 2048 nodes.
The Center is now well-positioned to do breakthrough science on this system with its
specific plan for simulating QCD at the physical point and a 10,000 atom density
functional theory simulation.

FIRST
29. The FIRST project is unique in the world and typifies the Center’s ability to use
applications needs to drive innovative computer architecture and systems research,which in turn delivers scientific results at the forefront of the applications field. This
has enabled the GRAPE technology to be deployed effectively for a wider range offrontier astrophysics applications. GRAPE is a hardware accelerator for direct force
summation gravitational N-body calculations. GRAPE can be used for direct
numerical simulation of collisional N-body systems (e.g., star clusters), or as a
hardware accelerator for the PP part of a P3M collisionless N-body simulation (e.g.,dark matter clustering). The integration of GRAPE with a high performance hostcluster, better suited to fluid dynamical calculations, enables new types of large-scale
coupled fluid/N-body systems to be attacked.
30. The Computational Astrophysics Group is to be congratulated for developing the firstsuch hybrid system, and is encouraged to seek out applications where this architecture
can best be exploited and showcased; for example, the formation of star clusters
which begin as fluid dynamical systems, pass through a coupled fluid/N-body phase,and end as purely N-body systems. CCS is uniquely positioned by virtue of FIRST to
break new ground here.

ILDG/JLDG
31. This is another example of a successful collaboration between the computer scientists
and particle physicists at the CCS over the past five years. They have taken thenational lead in the international ILDG project to build a global grid of regional data
grids for storing and sharing lattice QCD data, as well as developing in parallel theJapanese component grid infrastructure, JLDG, to support the lattice QCD
community within Japan. The key features of these projects are their close attention to10

Report of the Review Committee

30 November 2007

user needs, the early introduction into use by the community, and the rapid growth inuse across the world.
32. Key to the success of these projects was the definition, and international acceptance,of a standard XML-based mark-up language (QCDml) for the lattice QCD data,
developed by the ILDG Metadata Working Group under the leadership of Professor
Tomoteru Yoshié. Members of CCS have also played a significant part in the ILDG
Middleware Working Group which is defining the global architecture and theinterfaces between the various components.
33. The JLDG is being rolled out across five sites in Japan using Gfarm for file sharing.
The ILDG project is an on-going development to keep abreast of improvements ingrid technologies and to enhance functionality, but has already proved itself to be oneof the most successful data grids world-wide and is gaining recognition as such. It ishighly likely that it will be quickly accepted by the entire lattice field theory
community as the standard data management environment. Credit for this goes to theclose collaboration between users and developers from the outset, in which the CCS
team has been one of the best examples. The functionality of the middleware is rather
generic and opportunities exist for its application in other fields where communitywide agreement on metadata can be achieved.

Interdisciplinary Activities and Collaborations
34. The Review Committee found convincing evidence that the CCS is succeeding in its
mission to promote an interdisciplinary approach to computational science research.
Collaborative activities and opportunities were highlighted in all the presentations to
the Committee, indicating that all members of the CCS attach importance to it. The
success of the original CP-PACS collaboration between computer scientists andparticle physicists is a powerful example to other projects and continues to influencestrategies. The FIRST Project is a recent successful example of this model. Even withthe rapid expansion into a broader range of research areas since 2004, it will be achallenge for the CCS to find projects in which two (or more) disciplines have asufficiently important shared goal, at the same time, to take precedence over theirsingle-discipline efforts and then to nurture them through to successful completion.
Potentially exciting opportunities exist for all research groups, on various timescales,
although the Biological Sciences and Computational Media Groups are the furthestfrom the existing competencies of the Division of HPC Systems, whose work has had
the most unifying effect within the Center to date. Both this Division and the Divisionof Computational Informatics hold the keys to future major interdisciplinary projects.
Although well placed in its current mix of projects and expertise, and with anenviable track record, the Center will need continually to seek mechanisms andincentives for interdisciplinary working.
35. The Review Committee was impressed by the strong links which the CCS has grownwith the University’s Graduate School, which embeds it in a much larger research11Report of the Review Committee

30 November 2007

community, helping its research groups achieve critical mass, and providing it with avital source of PhD students. The Committee also strongly endorsed the planned dual
degree programme in computational science, which will expand the Center’s
education and training role. Although it will be a challenge to develop a curriculum
which is attractive to both students and the wider faculty within the University, thereward will be a stronger computational community and a source of appropriately
trained new researchers. These will also benefit the University and the future
employers of its students. The Center’s links with University researchers will also be
broadened through its provision of the University’s supercomputing service and thiswill be beneficial provided the service meets users’ needs and does not impose too
great a strain on the resources of the Center.
36. The CCS has a variety of external collaborations typical for internationallycompetitive research in computational science. In addition, it has played a prominentrole in the successful ILDG global infrastructure project. Consequently, today, the
CCS has a high international profile. As infrastructure and support for computational
science, as well as the research projects themselves, become increasingly
multinational, CCS will face greater competition for international leadership and so
will need to participate in a broader range of international projects if it is to continue
to be recognised as the center of excellence for interdisciplinary computational
science research in Japan. This strategy will also help to strengthen sub-criticalresearch groups.

Success of the Center in Achieving its Mission
37. The CCS, in continuing the work of the previous Center for Computational Physics,
has established over a period of 15 years a highly successful collaboration between
computer scientists and physicists that has built a series of world-class computers andused them to produce results at the forefront of computational physics. This is an
example to other areas of computational science and collaborative working has been
well integrated into the culture of the Center. The Review Committee strongly
supports the Center’s vision for computational science and the promotion of its
interdisciplinary approach should remain the core objective of CCS.
38. The reorganisation of the Center in 2004 has been successfully accomplished with a
big expansion in the number of faculty and the establishment of new research groups
with a breadth of applications that are at the forefronts of their respective fields.
Research themes have been chosen that will be of growing importance in the 21st
century. Some of these new groups are sub-critical in size, however, and they willneed to build strong collaborative links outside the Center, or be targeted for newhires. Even so, the Review Committee was very impressed by the scientificaccomplishments of the new groups in so short a time and the extent to which they
have integrated with the interdisciplinary culture of the Center. Most of the research
outputs were judged to be world class, or to have the potential to become so. In

12Report of the Review Committee

30 November 2007

several areas, novel approaches were being adopted which are exciting and hold theprospect for major breakthroughs.
39. The PACS-CS and FIRST projects are outstanding examples of major computerdevelopments which were driven by science needs and are now providing uniquecapabilities for leading-edge research. This ability to design, build and operate noveland competitive computer hardware targeted at challenging applications is at the very
heart of the Center and must be preserved. It derives from a mixture of environment
and talent that is not replicated anywhere else and gives the Center its competitiveedge.

Future Vision and Strategy
40. The Review Committee strongly endorses the Center’s overall future vision andstrategy to be a worldwide center of excellence in interdisciplinary computational
science, taking a global and long-term view. It recognizes that, after the majorchanges of the past three years, a period of consolidation is needed and it supports theplans of all the research groups and Divisions, while encouraging the Center toexpand its participation in international projects, its visitor programme and its support
for virtual organisations. Within the current scope of its research groups, the CCS
should maintain a portfolio of exciting research projects at the forefront ofcomputational and computer science, and a talented faculty engaged in this research.
It should continue to provide an environment which encourages interdisciplinarity
and in which shared goals can emerge and be nurtured.
41. The CCS should maintain an internationally competitive computing facility to support
its research projects so that it can focus appropriate computational resources to ensure
they have maximum impact in their fields. The Center’s strategy to take responsibility
for the University’s research-oriented supercomputing service will help it to maintaincontrol of appropriate systems and the planned “T2K” acquisition will achieve thisfor the next 3-4 years. However, the CCS has too few technical staff to support the
University service as well as use of its computers by a growing range of projects
which may no longer always include CCS research staff. The University must transfer
support staff, or the funding for them, to the CCS along with responsibility for its
supercomputer service. The CCS will need to introduce a more service-oriented user
support mechanism for this wider range of users, because the Center will risk its
excellent reputation if the service is poor, but it must be careful to ensure that thisservice activity does not dilute the Center’s research focus.
42. The CCS should continue to develop new computing technologies in the context ofthe most demanding applications needs and have the capability to bring thesetechnologies into use to make breakthroughs in specific areas of computational
science. Specialised hardware will continue to play a vital role in specific fields. The
expertise that CCS has acquired in embedding accelerators in general-purpose
clusters will have wider applicability in the future and should be actively pursued

13

Report of the Review Committee

30 November 2007

following-on from FIRST. The Review Committee recognises that the developmentof novel architectures is high risk, but it is also high reward and, although the funding
required for any particular development cannot be guaranteed, the Center’s successful
track record in this area is a major strength which is rare worldwide and should not belost. There is a rapidly evolving range of new technologies which might be deployed
to make significant advances in computational science and the Center is particularly
well-positioned to evaluate and exploit these.
43. The educational activities of the CCS will play a vital role in integrating it with thewider University community and with society. The expanded graduate programme
will be time-consuming for staff to develop and deliver, and some resistance to theinterdisciplinary concept may need to be overcome. However, the Center’s staff
should find this work rewarding and the outreach to students should generate newideas and new recruits. The building of a broadly based computational science
community and the promotion of interdisciplinarity should be seen by the University
as a major strategic opportunity which the CCS offers, and which could give it agenuine competitive advantage both in terms of its teaching and research. The
University should provide appropriate financial support for this expanded teaching
programme.
44. The CCS interdisciplinary research focus, educational activities and pioneering of
new technologies should enable it to play a major role in supporting initiatives suchas the National Next Generation Supercomputer (“Petaflops”) Project. The Center
should seek strategic partnerships with national projects such as this, which exploit its
complementary expertise in developing new application areas in computational
science and its capabilities as an icebreaker for innovative algorithms, highperformance software and new hardware technologies.

Other Recommendations
45. Overall, the Review Committee was impressed by the achievements of the CCS, its
interdisciplinary culture, its leadership and its vision for the future. The Committee
believes that the collective expertise in the Center and the research environment it has
built are unique worldwide. Already this has delivered world-leading scientificresults, giving the Center a high international standing. The expansion of the Centerin 2004 has given it the potential for a broader impact in both research and education,and has targeted areas that will be of strategic importance in the 21st century. The
Review Committee commends the Center to the University and recommends that the
University acknowledges its strategic value, supports the execution of its mission, andencourages the wider academic community to engage with its activities.

14