Supercomputer race: Tricky to boost system speed

The Top500 list is always climbing to new heights. Can we believe the hype?

An even greater bottleneck can crop up in programs that can't easily be broken into uniform, parallel streams of instructions. If a processor gets more than its fair share of work, all the others may wait for it, reducing the overall performance of the machine as seen by the user. Linpack operates on the cells of matrices, and by making the matrices just the right size, users can keep every processor uniformly busy and thereby chalk up impressive performance ratings for the system overall.

"As long as we continue to focus on peak floating-point performance, we are missing the actual hard problem that is holding up a lot of science," Loft says.

But the "hard problem" is getting the attention of computer and chip makers. IBM, which makes the Blue Gene family of supercomputers, has taken a systems approach.

Rather than cobbling together commodity processors with commodity interconnects like Ethernet or InfiniBand -- an approach that others have used -- IBM built five proprietary networks inside Blue Gene, each optimized for a specific kind of work and selectable by the programmer. Members of the Blue Gene family held the No. 1 and No. 2 positions on the Top500 list until June of this year.

By making memory access faster, and by doing it more cleverly, the absolute amount of memory in a system can be reduced, says Dave Turek, vice president of Deep Computing at IBM. As engineers work to build "exascale" computers (a thousand times faster than Roadrunner), that will be essential, he says.

"Going back a few years, you'd build a computer with the fastest processors possible and the most memory possible, and life was good," Turek says. "The question is, how much memory do you need to put on an exascale system? If you want to preserve the kinds of programming models you've had to this point, you'd better have a few hundred million dollars in your pocket to pay for that memory."

And it isn't just the purchase cost of memory that's a problem, Turek notes. Memory draws a lot of expensive power and generates a lot of heat that must be removed by expensive cooling systems.

Faster memory subsystems and faster interconnects will help, Turek says, but supercomputer users will also have to overhaul the programming methods that have evolved over the past 20 years if they hope to utilize the power of exascale computers.

He says users initially criticized Blue Gene for having too little memory, but eventually they were able to scale their applications to run well on 60,000 processors by changing the algorithms in their application code so they were more sparing in their memory use.

Join the PC World newsletter!

Error: Please check your email address.

Tags supercomputers

Our Back to Business guide highlights the best products for you to boost your productivity at home, on the road, at the office, or in the classroom.

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Gary Anthes

Computerworld
Show Comments

Essentials

Lexar® JumpDrive® S57 USB 3.0 flash drive

Learn more >

Microsoft L5V-00027 Sculpt Ergonomic Keyboard Desktop

Learn more >

Mobile

Lexar® JumpDrive® S45 USB 3.0 flash drive 

Learn more >

Exec

Lexar® JumpDrive® C20c USB Type-C flash drive 

Learn more >

HD Pan/Tilt Wi-Fi Camera with Night Vision NC450

Learn more >

Audio-Technica ATH-ANC70 Noise Cancelling Headphones

Learn more >

Lexar® Professional 1800x microSDHC™/microSDXC™ UHS-II cards 

Learn more >

Budget

Back To Business Guide

Click for more ›

Most Popular Reviews

Latest News Articles

Resources

PCW Evaluation Team

Azadeh Williams

HP OfficeJet Pro 8730

A smarter way to print for busy small business owners, combining speedy printing with scanning and copying, making it easier to produce high quality documents and images at a touch of a button.

Andrew Grant

HP OfficeJet Pro 8730

I've had a multifunction printer in the office going on 10 years now. It was a neat bit of kit back in the day -- print, copy, scan, fax -- when printing over WiFi felt a bit like magic. It’s seen better days though and an upgrade’s well overdue. This HP OfficeJet Pro 8730 looks like it ticks all the same boxes: print, copy, scan, and fax. (Really? Does anyone fax anything any more? I guess it's good to know the facility’s there, just in case.) Printing over WiFi is more-or- less standard these days.

Ed Dawson

HP OfficeJet Pro 8730

As a freelance writer who is always on the go, I like my technology to be both efficient and effective so I can do my job well. The HP OfficeJet Pro 8730 Inkjet Printer ticks all the boxes in terms of form factor, performance and user interface.

Michael Hargreaves

Windows 10 for Business / Dell XPS 13

I’d happily recommend this touchscreen laptop and Windows 10 as a great way to get serious work done at a desk or on the road.

Aysha Strobbe

Windows 10 / HP Spectre x360

Ultimately, I think the Windows 10 environment is excellent for me as it caters for so many different uses. The inclusion of the Xbox app is also great for when you need some downtime too!

Mark Escubio

Windows 10 / Lenovo Yoga 910

For me, the Xbox Play Anywhere is a great new feature as it allows you to play your current Xbox games with higher resolutions and better graphics without forking out extra cash for another copy. Although available titles are still scarce, but I’m sure it will grow in time.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?