HPCwire: Is it Time for Heterogeneous Supercomputing?

The Leading Source for Global News and Information Covering the Ecosystem of High Productivity Computing

HPCwire >> Blogs

Blog: From the Editor

July 14, 2006

Is it Time for Heterogeneous Supercomputing?

With all the talk of heterogeneous supercomputing over the last few years, one might get the impression that a revolution is on the horizon. Certainly, some in the industry have portrayed it as such. Non-scalar vector processors, coprocessor accelerators, MTA processors and FPGAs are available today and can offer tantalizing performance for targeted HPC workloads. The general idea behind heterogeneous processing is that a system containing different kinds of compute engines can be matched up with the type of code that runs most efficiently on them, increasing overall application performance.

From an evolutionary standpoint, heterogeneous processing makes sense. As systems become more complex, a greater amount of architectural specialization is required. This appears to be true for both man-made systems and biological systems. Compare the sophisticated structure of the human brain with the simple bundles of neurons that control many primitive invertebrates.

In the scheme of things, today's computers are still rather primitive themselves, but they already contain many heterogeneous elements. At the level of the chipset, specialized I/O and memory controller devices are commonly used to manage an increasing array of data sources and destinations. Computer memory has differentiated into distinct types, the most common ones being RAM, ROM and cache (3 levels). The CPU has remained as one of the last general-purpose components of the system. But as applications -- especially HPC applications -- become more complex and more demanding of computational performance, the pressure to tap other types of processing engines will increase.

FPGAs (Field Programmable Gate Arrays), in particular, have been getting a lot attention lately. They have gained a loyal following in the supercomputing community because they are reconfigurable, have wide applicability for HPC applications, and are commodity-based. And unlike coprocessors, vector processors and MTA processors, FPGAs are more general-purpose compute engines.

The growing interest of the HPC community in IBM's Cell chip is another example. Although the chip contains both a scalar (PowerPC) CPU and vector compute engines, it is not considered a true heterogenous processor itself. The scalar CPU is used to control the vector cores and manage the chip's memory hierarchy, rather than for computation. But theoretically the Cell could be used an additional compute resource within a conventional scalar-based system.

All of these non-scalar processors have one thing in common: compared to commodity CPUs, there is not much code support for them. So the software will have catch up. And that's not going to happen overnight.

Today, the HPC software community is focusing much of its energy on applying code parallelism to scalar processors. Homogeneous multi-core architectures are currently in the driver's seat in high performance computing, as it will soon be in almost all IT markets. This trend is likely to continue for some time. High-volume 64-bit processors that are supported by mature software ecosystems, such as the AMD Opteron and the Intel Xeon (and to a lesser extent, POWER/PowerPC and Itanium), are delivering economical supercomputing performance for the masses. The fact that other microprocessor architectures may be faster, cheaper or more energy-efficient than industry-standard hardware doesn't have much impact on the market until someone figures out a way to mainstream the newer technology.

That usually means developing the appropriate software support for these exotic processors. And if the goal is to integrate that hardware into a truly heterogeneous system, a la Cray's "Adaptive Computing" vision, it will also involve the much more challenging problem of managing heterogeneity in system software. Our own High-End Crusader addressed this issue just a few weeks ago in the article title "Heterogeneous Processing Needs Software Revolutions."

To its credit, Cray is the only company that has offered a vision of integrated heterogeneous computing, both in hardware and software. But currently it's just a vision, not a product. Even the "Baker" petaflops system they plan to deliver to ORNL in 2008 is a homogeneous Opteron-based machine. Cray will implement their heterogeneous Cascade architecture when and if DARPA selects them for Phase 3 of the HPCS program. But the company says it intend to move forward with their Adaptive Computing roadmap whether they continue with HPCS or not. They believe that the next generation of high performance applications will require a variety of specialized compute engines to obtain reasonable performance (and use reasonable amounts of energy). Cray appears to be committed to that vision.

Other HPC vendors are venturing into the heterogenous space as well. SGI's Reconfigurable Application Specific Computing (RASC) technology represents their advanced FPGA solution. Sun Microsystem's recently deployed TSUBAME supercomputer incorporates ClearSpeed coprocessors (not in use yet, however) as part of that system. Other OEMs may come out with their own solutions in the next few years as software libraries and programmer development environments that support these new processor types become available.

But a heterogeneous architecture "revolution" seems unlikely while homogeneous multi-core architectures are so dominant in the commercial space. Revolutions usually start because the masses are unhappy, and that is not the case today. An "evolution" is far more likely and it is currently in progress. The mainstreaming of heterogeneous systems will happen sooner or later because parallelism, itself, has its limits. Bandwidth, memory access, and software scalability are already inhibiting performance on even moderately scaled systems (thousands of processors). Once we start building petaflops machines, these limitations will become even more aggravating. Heterogenous computing offers a way forward. Join the evolution!

-----

As always, comments about HPCwire are welcomed and encouraged. Write to me, Michael Feldman, at editor@hpcwire.com.

Posted by Michael Feldman - July 14 @ 12:00AM

(Digg, Technorati, more)

Discussion

There are 0 discussion items posted.

Join the Discussion

You must be a registered user in order to comment on HPCwire stories.

Members enjoy:

	Access to Special Content, including Podcasts, Webcasts, and Whitepapers and more!
	Ability to take an active role in the discussions that are shaping the HPC technology discipline!
	Special offers available only to HPCwire members!

Become a Registered User Today!

Registered Users Log in Here to Comment

Email Address:	Password (case sensitive)

Remember me	Forgot Password?

Michael Feldman

Michael Feldman is the editor of HPCwire.

More Michael Feldman

Feature Articles

Chips Ahoy: Vendors Show Off Their Latest Silicon

Chipmakers converged on San Francisco this week to talk up their newest semiconductor products at the International Solid State Circuits Conference (ISSCC). Of particular interest to the HPC crowd are Intel's Westmere EP and "Tukwila" Itanium 9300, and IBM's POWER7.
Read More...

The Week in Review

TACC's Ranger supercomputer celebrates its second year of enabling important research; Microsoft partners with NSF to bring cloud services to researchers; and NSF submits its fiscal year 2011 budget request. We recap those stories and more in our weekly wrapup.
Read More...

NASA Looks to Move Science Apps Into the Cloud

It seems only natural that the US space agency would be casting its eyes toward the clouds. Sure enough, NASA is now looking to cloud computing to optimize the operation of the agency's IT infrastructure for some of its science codes. Like many commercial businesses and government organizations, NASA is being asked to do more computing with fewer datacenter resources.
Read More...

Read more HPCwire features...

Top Headlines

IBM Releases Energy Efficient Power7 System

Feb 09 | eWeek Europe | Company says new high-end servers will deliver "intelligent performance." Read more...

Inductive Coupling Packs Flash Drive in a Chip

Feb 09 | EE Times | Wireless technology promises energy-efficient chip-to-chip communication. Read more...

IBM, Microsoft Help Create Montana Supercomputer

Feb 08 | eWeek | A new kind of Rocky Mountain high. Read more...

AMD Aims for GPUs in Mainstream Servers Starting 2012

Feb 08 | Computerworld | Chip maker hopes to bring CPU-GPU processors to servers in two years. Read more...

Graphene Transistors That Work at Blistering Speeds

Feb 05 | Technology Review | IBM has created graphene transistors that leave silicon ones in the dust. Read more...

Read more headlines...

Featured Whitepapers

Virtualization for Aggregation And The vSMP Architecture™

Jan 12 | | In-depth look at vSMP Foundation server virtualization technology, technical implementation, use cases and capabilities. The technical whitepaper provides an architectural overview and details on the three vSMP Foundation products: vSMP Foundation for SMP, vSMP Foundation for Cluster and vSMP Foundation for Cloud.

Copper Cable Technologies for High Performance Computing

Jan 18 | | This white paper discusses Gore’s copper cable assemblies, and how they continue to exceed the standards for providing reliable, cost-effective solutions for high-performance computer applications.

Appro Assists LLNL with Cluster Designed for Extreme Scale Visualization

Jan 11 | | LLNL is home to some of the fastest computers in the world. In 2012, LLNL expects to have the Sequoia supercomputing cluster operational with a projected performance of over 20 PFLOP/s. These systems will focus on strengthening the foundations of predictive simulation through running large suites of complex simulations and then comparing model predictions with experimental data. To visualize this project’s large amount of data, LLNL requested an Appro Supercomputing Cluster specifically designed to support interactive data analysis.

View the White Paper Library

Multimedia

Webcast: Virtualized Data Center Roundtable

Join this online panel discussion for live Q&A with leading industry experts, analysts, and end-users to discuss the latest innovations, best practices, barriers to implementation, and measurable benefits of server virtualization with a particular focus on today's real world solutions.

Webcast: Watch SC09 Birds of a Feather Video: Scalable Fault-Tolerant HPC Supercomputers

Learn about scalable fault-tolerant architectures and examples of energy efficient and scalable supercomputing clusters using dual QDR InfiniBand to combine capacity computing with network failover capabilities with the help of programming languages such as MPI and a robust Linux cluster management package.

Webcast: High Performance Computing for a Smarter Planet

LIVE@SCO9: The IBM team discusses new innovations in hardware, software and services that help clients better understand their workloads and get insight from their R&D efforts. Technology demonstrations include the soon-to-be-released Power7 HPC processor, the DCS990 system with 2.4 petabytes of storage, the xCAT management tool, secure HPC cloud computing and more. Winners of two HPCwire Readers' and Editors’ Choice Awards! Take the IBM virtual tour at SC09 or more information go online to: http://www-03.ibm.com/systems/deepcomputing/sc09.html