Will Roadrunner Be the Cell’s Last Hurrah?

By Michael Feldman

October 27, 2009

With all the recent hoopla about GPGPU acceleration in high performance computing, it’s easy to forget that Roadrunner, the most powerful supercomputer in the world, is based on a different brand of accelerator. The machine at Los Alamos National Laboratory uses 12,960 IBM PowerXCell 8i CPUs hooked up to 6,480 AMD Opteron dual-core processors to deliver 1.1 petaflop performance on Linpack.

Because of the wide disparity in floating point performance between the PowerXCell 8i processor and the Opteron, the vast majority of Roadrunner’s floating point capability resides with the Cell processors. Each PowerXCell 8i delivers over 100 double precision gigaflops per chip, which means the Opteron only contributes about 3 percent of the FLOPS of the hybrid supercomputer.

Some of those FLOPS are already being put to good use, though. This week, Los Alamos announced that the lab had completed its “shakedown” phase for Roadrunner. Because the machine was installed in May 2008, this has allowed researchers over a year to experiment with some big science applications.

These unclassified science codes included a simulation of the expanding universe, a phylogenic exploration of the evolution of the Human Immunodeficiency Virus (HIV), a simulation of laser plasma interactions for nuclear fusion, an atomic-level model of nanowires, a model of “magnetic reconnection,” and a molecular dynamics simulation of how materials behave under extreme stress. All of these codes were able to make good use of the petascale performance of the Roadrunner.

Now that the shakedown period has concluded, the NNSA will move in to claim those FLOPS for nuclear weapons simulations. Since these applications are obviously of a classified nature, we’re not likely to hear much about their specific outcomes. Open science codes will still get a crack at the machine, but since Roadrunner’s primary mission is to support US nuclear deterrence, the unclassified workloads will presumably get pushed to the back of the line.

The bigger question is what are the longer-term prospects of a hybrid x86-Cell system architecture and the Cell processor, in general, for the high performance computing realm? Unlike GPUs or FPGAs, Cell processors contain their own CPU core (a PowerPC) along with eight SIMD coprocessing units, called Synergistic Processing Elements (SPE), so the chip represents a more fully functional architecture than its competition. Despite that advantage, the Cell’s penetration into general-purpose computing has remained somewhat limited. Although the original Cell processor was the basis for the PlayStation3 gaming console and the double-precision-enhanced PowerXCell variant has found a home in HPC blades, neither version is a commodity chip in the same sense as the x86 CPU or general-purpose GPUs. The result is that Cell-based solutions are strewn rather haphazardly across the HPC landscape.

Besides the high-profile Roadrunner system, IBM also offers a standalone QS22 Cell blade, which is deployed at a handful of sites, including the Interdisciplinary Centre for Mathematical and Computational Modeling at the University of Warsaw and Repsol YPF, a Spanish oil and gas company. As it turns out, these systems are among the most energy efficient, with the Warsaw system currently sitting atop the Green500 list. Other Cell accelerator boards are available from Mercury Computer Systems, Fixstars, and Sony, but I’ve yet to hear of any notable HPC deployments resulting from these products.

Cell processor developer tools certainly exist, but no standard environment has come to the fore. This is rather important since the heterogeneous nature of the Cell architecture means programming is inherently more difficult. IBM, of course, provides its own software development kit for the architecture. Outside of Big Blue, Mercury Computer Systems has a Cell-friendly Multicore Plus SDK, and software vendor Gedae sells a compiler. RapidMind offers Cell support in its multicore development platform, but since the company was acquired by Intel, its Cell-loving days are likely coming to a close. French software maker CAPS was planning to offer Cell support in its HMPP manycore development suite sometime this year, but that hasn’t come to pass.

With NVIDIA’s Fermi GPU architecture poised to make a big entrance into high performance computing in 2010, IBM will have to make a decision about adding GPU acceleration to its existing HPC server lineup. Server rival HP has apparently already committed to including Fermi hardware in its offerings. Last week Georgia Tech announced HP and NVIDIA would be delivering a sub-petaflop supercomputer to the institute in early 2010. That system will be based on Intel Xeon servers accelerated by Fermi processors. Other HPC vendors, including Cray, have announced plans to bring Fermi into their product lines. If GPUs become the mainstream accelerator for HPC servers, IBM will be forced to follow suit.

That’s not to say IBM will give up on its home-grown Cell chip. Big Blue has a tradition of offering a smorgasbord of architectures to its customers, especially in the HPC market. Today the company has high-end server products based on x86 CPUs, Blue Gene (PowerPC-based) SoCs, Power CPUs, and the Cell processor. Adding GPU-accelerated hardware wouldn’t necessarily mean ditching the Cell.

On the other hand, IBM has to consider if it wants to reinvest in the architecture to keep up with the latest GPU performance numbers from NVIDIA and AMD, which would mean getting a single Cell processor to deliver hundreds of gigaflops of double-precision performance. IBM is certainly capable of building such a chip, but there’s little motivation to do so. With no established base of customers clamoring for Cell-equipped supercomputers and with a relatively small volume of Cell chips from which to leverage high-end parts, it’s hard to imagine that Big Blue will be doubling down on its Cell bet.

Subscribe to HPCwire's Weekly Update!

Be the most informed person in the room! Stay ahead of the tech trends with industy updates delivered to you every week!

Deep Learning at 15 PFlops Enables Training for Extreme Weather Identification at Scale

March 19, 2018

Petaflop per second deep learning training performance on the NERSC (National Energy Research Scientific Computing Center) Cori supercomputer has given climate scientists the ability to use machine learning to identify e Read more…

By Rob Farber

Mellanox Reacts to Activist Investor Pressures in Letter to Shareholders

March 16, 2018

Activist investor Starboard Value has been exerting pressure on Mellanox Technologies to increase its returns. In response, the high-performance networking company on Monday, March 12, published a letter to shareholders outlining its proposal for a May 2018 extraordinary general meeting (EGM) of shareholders and highlighting its long-term growth strategy and focus on operating margin improvement. Read more…

By Staff

Quantum Computing vs. Our ‘Caveman Newtonian Brain’: Why Quantum Is So Hard

March 15, 2018

Quantum is coming. Maybe not today, maybe not tomorrow, but soon enough. Within 10 to 12 years, we’re told, special-purpose quantum systems will enter the commercial realm. Assuming this happens, we can also assume that quantum will, over extended time, become increasingly general purpose as it delivers mind-blowing power. Read more…

By Doug Black

HPE Extreme Performance Solutions

Achieve Optimal Performance at Scale with High Performance Fabrics for HPC

High Performance Computing (HPC) is unlocking a new era of speed and productivity to fuel business transformation. Rapid advancements in HPC capabilities are helping organizations operate faster and more effectively than ever, but in today’s fast-paced marketplace, a new generation of technologies is required to reach greater scalability and cost-efficiency. Read more…

How the Cloud Is Falling Short for HPC

March 15, 2018

The last couple of years have seen cloud computing gradually build some legitimacy within the HPC world, but still the HPC industry lies far behind enterprise IT in its willingness to outsource computational power. The m Read more…

By Chris Downing

Deep Learning at 15 PFlops Enables Training for Extreme Weather Identification at Scale

March 19, 2018

Petaflop per second deep learning training performance on the NERSC (National Energy Research Scientific Computing Center) Cori supercomputer has given climate Read more…

By Rob Farber

How the Cloud Is Falling Short for HPC

March 15, 2018

The last couple of years have seen cloud computing gradually build some legitimacy within the HPC world, but still the HPC industry lies far behind enterprise I Read more…

By Chris Downing

Stephen Hawking, Legendary Scientist, Dies at 76

March 14, 2018

Stephen Hawking passed away at his home in Cambridge, England, in the early morning of March 14; he was 76. Born on January 8, 1942, Hawking was an English theo Read more…

By Tiffany Trader

Hyperion Tackles Elusive Quantum Computing Landscape

March 13, 2018

Quantum computing - exciting and off-putting all at once - is a kaleidoscope of technology and market questions whose shapes and positions are far from settled. Read more…

By John Russell

Part Two: Navigating Life Sciences Choppy HPC Waters in 2018

March 8, 2018

2017 was not necessarily the best year to build a large HPC system for life sciences say Ari Berman, VP and GM of consulting services, and Aaron Gardner, direct Read more…

By John Russell

Google Chases Quantum Supremacy with 72-Qubit Processor

March 7, 2018

Google pulled ahead of the pack this week in the race toward "quantum supremacy," with the introduction of a new 72-qubit quantum processor called Bristlecone. Read more…

By Tiffany Trader

SciNet Launches Niagara, Canada’s Fastest Supercomputer

March 5, 2018

SciNet and the University of Toronto today unveiled "Niagara," Canada's most-powerful supercomputer, comprising 1,500 dense Lenovo ThinkSystem SD530 high-perfor Read more…

By Tiffany Trader

Part One: Deep Dive into 2018 Trends in Life Sciences HPC

March 1, 2018

Life sciences is an interesting lens through which to see HPC. It is perhaps not an obvious choice, given life sciences’ relative newness as a heavy user of H Read more…

By John Russell

Inventor Claims to Have Solved Floating Point Error Problem

January 17, 2018

"The decades-old floating point error problem has been solved," proclaims a press release from inventor Alan Jorgensen. The computer scientist has filed for and Read more…

By Tiffany Trader

Japan Unveils Quantum Neural Network

November 22, 2017

The U.S. and China are leading the race toward productive quantum computing, but it's early enough that ultimate leadership is still something of an open questi Read more…

By Tiffany Trader

Researchers Measure Impact of ‘Meltdown’ and ‘Spectre’ Patches on HPC Workloads

January 17, 2018

Computer scientists from the Center for Computational Research, State University of New York (SUNY), University at Buffalo have examined the effect of Meltdown Read more…

By Tiffany Trader

IBM Begins Power9 Rollout with Backing from DOE, Google

December 6, 2017

After over a year of buildup, IBM is unveiling its first Power9 system based on the same architecture as the Department of Energy CORAL supercomputers, Summit a Read more…

By Tiffany Trader

Fast Forward: Five HPC Predictions for 2018

December 21, 2017

What’s on your list of high (and low) lights for 2017? Volta 100’s arrival on the heels of the P100? Appearance, albeit late in the year, of IBM’s Power9? Read more…

By John Russell

Nvidia Responds to Google TPU Benchmarking

April 10, 2017

Nvidia highlights strengths of its newest GPU silicon in response to Google's report on the performance and energy advantages of its custom tensor processor. Read more…

By Tiffany Trader

Russian Nuclear Engineers Caught Cryptomining on Lab Supercomputer

February 12, 2018

Nuclear scientists working at the All-Russian Research Institute of Experimental Physics (RFNC-VNIIEF) have been arrested for using lab supercomputing resources to mine crypto-currency, according to a report in Russia’s Interfax News Agency. Read more…

By Tiffany Trader

Chip Flaws ‘Meltdown’ and ‘Spectre’ Loom Large

January 4, 2018

The HPC and wider tech community have been abuzz this week over the discovery of critical design flaws that impact virtually all contemporary microprocessors. T Read more…

By Tiffany Trader

Leading Solution Providers

GlobalFoundries, Ayar Labs Team Up to Commercialize Optical I/O

December 4, 2017

GlobalFoundries (GF) and Ayar Labs, a startup focused on using light, instead of electricity, to transfer data between chips, today announced they've entered in Read more…

By Tiffany Trader

How Meltdown and Spectre Patches Will Affect HPC Workloads

January 10, 2018

There have been claims that the fixes for the Meltdown and Spectre security vulnerabilities, named the KPTI (aka KAISER) patches, are going to affect applicatio Read more…

By Rosemary Francis

Perspective: What Really Happened at SC17?

November 22, 2017

SC is over. Now comes the myriad of follow-ups. Inboxes are filled with templated emails from vendors and other exhibitors hoping to win a place in the post-SC thinking of booth visitors. Attendees of tutorials, workshops and other technical sessions will be inundated with requests for feedback. Read more…

By Andrew Jones

V100 Good but not Great on Select Deep Learning Aps, Says Xcelerit

November 27, 2017

Wringing optimum performance from hardware to accelerate deep learning applications is a challenge that often depends on the specific application in use. A benc Read more…

By John Russell

Lenovo Unveils Warm Water Cooled ThinkSystem SD650 in Rampup to LRZ Install

February 22, 2018

This week Lenovo took the wraps off the ThinkSystem SD650 high-density server with third-generation direct water cooling technology developed in tandem with par Read more…

By Tiffany Trader

AMD Wins Another: Baidu to Deploy EPYC on Single Socket Servers

December 13, 2017

When AMD introduced its EPYC chip line in June, the company said a portion of the line was specifically designed to re-invigorate a single socket segment in wha Read more…

By John Russell

World Record: Quantum Computer with 46 Qubits Simulated

December 18, 2017

Scientists from the Jülich Supercomputing Centre have set a new world record. Together with researchers from Wuhan University and the University of Groningen, Read more…

New Blueprint for Converging HPC, Big Data

January 18, 2018

After five annual workshops on Big Data and Extreme-Scale Computing (BDEC), a group of international HPC heavyweights including Jack Dongarra (University of Te Read more…

By John Russell

  • arrow
  • Click Here for More Headlines
  • arrow
Share This