SC09, Computing for a Changing World
Report, Riken“Never send a human to do a machine job”

The SC09 Conference put together the best researches, scientists,industries and laboratories in the super-computing field in Portland Oregon lastNovember. This conference represents the best opportunity to present and discuss
the new advances in all areas of supercomputing like networking, hardware,
software and I/O among many others.
The conference consisted of many events under the same roof, the Oregon
Convention Center. The main event or the bounding one is the exhibition area
where the principal industries and companies in the business as long with
universities and laboratories can show their new discovers and research. There aremany other events around this like the tutorials, masterworks, poster sessions,forums, etc.
The organization was neat and orderly developed, some unexpectedchanges of room happened but due to the number of attendances. The earlyregistration could be done the day before the official start day to avoid long queues.
Each participant was given a handbag with all the information about the conferenceplus magazines related to super computing, the batch and important guides like afloor-map or detailed schedules.

The freedom to swap between tutorials and presentations give an excellent
chance to get a broad idea of more topics also.

Figure No.1 Oregon Convention Center Hall
(Right Close-Up: Japan, France and Costa Rica Flags)

During the tutorials many different topics were presented from new highspeed networks to I/O and from High Performance on GPU to the new OpenCL
platform.
High Performance on GPU seemed to be a new important subject toanalyze. Since its rapid introduction and adoption in the market the GPGPU
technology seems to have come a long way. One of the tutorials explained quickly
the GPU history which is one of the fastest adopted devices in supercomputing.
The general purpose GPU computing or computing on the graphics card gives theability to program the GPU as a general device meaning not only for graphics. The
advance of this approach is that GPU GFLOPs are several orders of magnitude
bigger than that of ordinary CPUs. Therefore the power inside a GPU can be used
to solve numerical problems or any general problem now. If this performance is put
together like in a cluster then this power is increased dramatically.
Therefore the interest of many new companies to explore this technology as
an alternative to super-computing as dedicated clusters or heterogeneous CPUGPU clusters.

In the High Performance Computing with GPU several ideas and techniques
were discussed to improve even more the performance than a programmer can getfrom the GPUs. For instance fusing kernels as much as possible to minimize
redundant access to memory or avoid if-clause statements. Another interesting
GPU advantage presented at the tutorial is the initial-to-program time versus
improve-benefit of using GPU compared to other technologies. Using results takenfrom MIT’s 6.963 course they found that after a 10-hour studying and programmingwith CUDA they obtained a 330x speed up while on the time they obtained only a9x speed up using C/SSE and even worst using Matlab. This clearly showed how
CUDA gave easy access to GPU programming with great results.
In the exhibition-booth-part of the conference nVIDIA gave presentations
about their new product named Fermi which is the next-generation GPU devices.
These new devices promises even higher FLOPs than current Tesla GPUs byincreasing the number of stream processors among other improvements. Thesecards will speed up double precision computing which up until now has been noteven close as fast as single precision. They promise an 8-times speed up which isgood but still not good enough is we compare the old single precision with new
single precision.

Figure No.2 Booth Preparation

A disadvantage using GPU computing however is that the cards cannot
share data directly between them therefore one must use a bridge to send thisinformation, usually the CPU. Clearly this is an undesired additional overhead thatwould be better to avoid, nevertheless there is no way to avoid it with the presenthardware. Fortunately some companies are already working a way around theproblem to share information directly between GPUs.
Until now GPU computing has been possible thanks to CUDA from nVIDIA,
which is a C extension language consisting of APIs designed to program at will theGPU. However this limits the portability of the program since other brands of cards
are not able to compile or run general purpose programs. This solve this issue in atutorial and other presentations a new standard was introduced called OpenCL,
which is a multi-platform programming extension. Using OpenCL will give thepossibility to port one program using any type of hardware. This will be clearly agreat breakthrough in the current system however it brings up some questions likethe performance obtained in a program optimized for a specific card in acompetitor’s card. Nevertheless as a joint effort to bring standardization andportability it must be noted as a to-watch innovation.

Figure No.3 Excerpt from Exposition Booth Floor

Different universities from Europe, USA, Japan and others were present at
the conference presenting their research in climate, fluid dynamics, nuclear physics

and other main applications of super-computing. Super-Computing centers as wellpresented their innovations in hardware and applications.
A particularly interesting presentation was in the NASA booth regarding
CFD applications. One of these applications is the support for vehicle assemblybuilding, in which they modeled the fire scenario in case of an accident inside thevehicle rockets facility. Another application they are working on is related to thenew space program and its launching vehicle. They have been developing
numerical simulations to study the behavior of the atmosphere around the rocket
during a launch as well as the movement and behavior of the fuel ejected from thebooster. These researches require high accurate numerical methods creating agreat complexity, different mesh sizes and unstructured grids sometimes.
Additionally NASA uses its own rendering program which is outstanding to presentresults.
This bring us to visualization, this is another important application of supercomputing. Most of the results nowdays obtained by super-computers are so vastand huge that they cannot be easily rendered. The data by itself might not be very
helpful if there is not a reasonable way to interpret them therefore the importanceof scientific rendering. However with the increasing data size visualizing isbecoming itself in a super-computing challenge.
Very interesting efforts to do large-scale rendering were also presented at
the conference. Some of the most impressive were renderings of millions of points
sent over the network to a remote display where they were not only rendered but
also manipulated. Research like that of Los Alamos National Laboratory named“Interactive Remote Large-Scale Data Visualization via Prioritized Multi-Resolution
Streaming” presented different approaches to render large amounts of data. Someof the ideas were to render first a coarse resolution and produce a finer resolution
with time or maybe if the user zoomed in a particular zone then refined thatparticular area. An interesting challenge discussed in the rendering presentations
was the hardware versus data-set size issue, which basically means that we areproducing larger and larger amounts of data and with current displays is impossible
to achieve that extremely high resolution. Therefore the solution must be foundeither improving the displays or taking advantage of this and for instance render
only a part of the dataset and not the complete domain which anyway won’t becorrectly displayed.
The plenary speech on wednesday was given by Doctor Leroy Hood, one of
the eleven scientists who, in 1985, initiated the Human Genome Project. His talkwas under the Bio-Computing aspect of the conference. He explained in somedetailed the work he has been doing plus his work for the future.

Figure No.4 Doctor Leroy Hood Plenary Speech at SC09

Clearly decoding gene information is a remarkably intensive task for any
machine therefore the importance of super-computing to analyze these results.
Nevertheless Doctor Hood is not only interested in this but currently he isinteresting into cancer research. In this research he is interested into developing acell-by-cell grow of the malign tissue as opposite to today-used approach where
the cancer tissue is treated as a whole. In this kind of proposal we are talking about
thousands and millions of millions of cells reproducing and interacting between
each other, this is a new area of super-computing where all the resources will beneeded to understand correctly the behavior of cancer grow and thus come up witha cure.

During the conference the new Top 500 list was released introducing OakRidge National Laboratory’s super-computer called Jaguar as the new number one
in the world. It has over 240.000 processors with a 1.75 Petaflop/s performancesetting a new road in Peta-scale computing.

Figure No.5 Top500 November 2009 List

On thursday the main event was the keynote speech delivered by Nobel
Prize Laurette and former USA Vice-President Al Gore. Al Gore was a key factor inthe development of the internet back in the 70s and 80s while serving as a US
senator and since that time he also consumed his time devoted to global climate
activism. Known for his Oscar-winning documentary “An Inconvenient Truth” Al
Gore presented an interesting speech trying to merge super-computing withclimate change prevention.

Figure No. 6 Former Vice-President Al Gore giving Keynote Speech(Photograph Credit: ©SC09)

Therefore the main point of his interesting talk was about the application of
the super-computing infrastructure to climate modeling in order to understand andprevent natural disasters produced by pollution.
Finally one last remark but present throughout the conference was the ExaScale Super-Computing which is the next natural step for this field. After reachingand passing the Peta-Scale barrier all eyes are now in the next challenge.
However the next step might not be as easy as just ensemble more
processors to increase the performance of a super-computing. There are several
and new problems to solve before thinking about going into Exa-Scale. According
to presentations during the conference, panels and reports some of the main
issues to tackle are: lack of cooperation, the industries, research laboratories anduniversities are not really working together to achieve this goal. Therefore muchresource is wasted instead of combining and sharing knowledge. Some suggestion
to solve this problem is to create a global network to share information. Anotherinteresting fact is that up until now scientists have enjoyed automatic improvementof their programs with each release of a new and more powerful processor
however this is no longer the case and in order to achieve a better performance it
is necessary to develop efficient code. This is going to be specially true for ExaScale computing since the program should be as efficient as possible not to waste
the huge amount of hardware available. One sort of new issue raising with exascale computing is fault control and error prevention. With currents technologies
the influence of a hardware failure in the code is not really critical but with the new
hardware the presence of errors will grow and techniques for checking/restart andecc for instance are going to become more and more important.
Finally maybe the two main issues when thinking on a exa-scale computing
facility are not precisely how to find more powerful processors or higher speednetworks but space and energy. In fact even current supercomputers require alarge area to be ensemble in, in the future with exa-scale computers will require
even larger areas what creates a big trouble with industries and laboratories.

Second and also as important as the previous issue is the energy. The energy topower up and keep running these monstrous machines will be very considerable
and it is very important to analyze if the electrical system would support suchmachines.
In more relaxed terms, the conference took place in the city of Portland
Oregon a very photogenic and peaceful city. People were warm and kind and it
had a great environment. The last night the organization prepared a reception atthe Portland Center for the Performing Arts that was very entertaining and relaxing.

Figure No.7 Portland City and the Portland Center for the Performing Arts

Once again I want to deeply thank Riken for giving me this great opportunity
to explore the world of a Super-Computing conference as their reporter.

Marlon Arce Acuna