Multicore systems dragged down by lagging software

Virtualization fills gap while software industry struggles to catch up with Intel, AMD advances

Trying to boost the IT capabilities at his digital forensics company, Brian Dykstra invested in a server that uses quad-core processors. After all, he figured, more cores means a more-powerful machine that can do far more work than a single-core system.

However, after shelling out money for the new technology, Dykstra found three of the four cores were sitting idle, because the software he was running wasn't built to make use of multiple cores.

Dykstra isn't alone in his disappointment with the lack of software for multicore chips. As hardware firms increase the number of cores in single chips, most software simply isn't keeping pace, creating a huge drag on efforts to take advantage of the potentially significant hardware-based performance improvements.

In order for users to see those performance gains, software designed for use on multicore chips must be built to let different cores handle different tasks in an application at the same time.

Dykstra noted that while some server software from major vendors like Microsoft Corp. and Oracle Corp. has been partially multithreaded, for the most part there is a dearth of such applications.

Once Dykstra, co-founder and a senior partner at Columbia-Md.-based Jones Dykstra & Associates, identified which applications were most important to his firm, then he compiled a list of vendors, picked up the phone and started haranguing them to add support for the chips. He didn't identify the vendors.

Despite the experiences of Dykstra and others, some IT managers have been able to cut costs and hardware needs by using multicore technology in virtualization projects.

For instance, when a company goes down the virtualization road with multicore systems, each core is assigned its own virtual machine, allowing each to run a separate application.

Virtualization on multicore chips is working out very well for Bruce McMillan, manager of emerging technologies at the U.S. division of Solvay Pharmaceuticals Inc. in Marietta, Ga., who has scaled up his virtual machine total by 50% while cutting the number of physical servers in his data center almost in half.

McMillan said he had been running 100 virtual machines on eight servers with single-core processors. He added two dual-core servers about a year ago and he was able to scale from 100 to 150 virtual machines.

About a month ago, Solvay installed a quad-core server, which enabled it to retire three single-core servers. The company is now in the process of adding two more quad-core servers, which will replace all of the remaining single-core systems, according to McMillan.

"It's saved me $500,000 just in hardware costs" so far, he said. "I can have much higher consolidation ratios than I had before. This is about server consolidation."

McMillan said he's looking forward to getting more multithreaded software but, for today, he's happy that the multicores are allowing him to do more work with less hardware.

"It's a new level of scalability," he said. "It's enabled us to really reduce our footprint in the data center. It's reduced our cooling costs. It's giving us less physical servers to manage. The maintenance contracts are cheaper. We're using fewer network portals because we have fewer machines."

Quantum Leaps

And the lack of multithreaded software certainly hasn't slowed the development of multicore processors by the world's top chip makers.

Just this month, Santa Clara, Calif.-based Intel Corp. released its new Xeon 7400 server processor series, which includes six-core technology, a new high-water mark in the semiconductor industry.

And while the step from quad-core to six-core processors is a big one, Intel and other chip makers are expected to leapfrog that benchmark very soon.

Eight-core versions of the company's next-generation chip, dubbed Nehalem, are expected to go into production next year. The first releases of the Nehalem chip family are expected to be quad-core server chips due to ship in the fourth quarter of this year.

At the same time, Advanced Micro Devices Inc., still far behind Intel when it comes to producing anything more than quad-core chips, has released its road map for pushing the processor envelope.

The Sunnyvale, Calif., company expects to ship its six-core Istanbul server processor in the second half of 2009 and a 12-core server processor during the first half of 2010.

And IBM is building supercomputers that run the eight-core Cell chip, which the company jointly developed with Sony Corp. and Toshiba Corp. to run large computations on Sony's PlayStation 3 video game system.

Possibly the farthest-reaching project is underway in labs where Intel engineers are working on an 80-core processor. The company showed off the technology at a conference in early 2007.

There have been no publicly announced plans to actually build such a processor, but analysts say the research into an 80-core chip is a hint of the future -- possibly the not-so-distant future.

"You know, at this point, everyone knows we're going to go up with the multicores -- quads to six, to eight, to 12 cores," said Jim McGregor, an analyst at In-Stat in Scottsdale, Ariz.

"The road maps are out there for multiple cores," he added, allowing IT managers to start planning to take advantage of the technology. "We know the track the technology is taking. This is an evolutionary cycle."

McGregor said he expects to see 16 cores on a chip within 18 months to two years. He noted that the chip industry is almost to the point where it is doubling the number of cores on processors every two years.

Performance for Whom?

The issue for IT executives today is to try and determine how helpful that doubling -- or any increase in processor cores for that matter -- might really be until the software problem is solved.

Just ask Dykstra.

"It's really disappointing when you fire up a quad-core and then you see it's really only running on one core," Dykstra said. "All that extra money and expense, and you're not really getting a boost in speed."

In most cases today, only one core of a quad-core chip is used to run software "to its max usage potential, while the other three cores are just sitting there doing nothing," Dykstra said. Therefore, "you have 25% CPU usage" in most cases. Taking advantage of all the cores, he added would boost performance by 75%.

"It [means] more data is pushed through, [there is] quicker delivery time to clients and it's more money," he added. "That's why we go to vendors and harangue them to do better."

The effort to get multithreaded software will likely take longer than many IT managers hope, say analysts. And there are some very basic reasons for that.

First and foremost, building multithreaded software is expensive. It's also a difficult task, especially for the many developers who learned how to code single-threaded software, and have done nothing but that for years.

"We have a serious developer problem," noted Rob Enderle, an analyst at the Enderle Group in San Jose. "People just don't know how to develop" for multicore machines.

"The environment has been single-threaded for so long that developers really haven't developed the skills. It's difficult to take things apart, make them run separately and then have them come together perfectly at the end," he added.

In a statement, Microsoft cited a lack of tools built for creating multithreaded software.

Margaret Lewis, director of commercial solutions at AMD, predicted that software companies will make major advances in writing multithreaded code within five years.

But even when multithreaded software starts flowing from vendors, it won't help the many large companies that run older, internally developed applications that can't easily be replaced. Eventually, companies that want those applications to utilize multicore processors will have to take on a massive job of either rewriting or replacing the software.

Today's volatile economy also isn't helping the cause of multithreaded software development, as companies must prove a strong business benefit when seeking to build or buy new technologies, said Joanne Kossuth, vice president of operations and CIO at the Franklin W. Olin College of Engineering in Needham, Mass.

"The challenge is, in the economic arena we're in right now, cost is critical," she said. "How much will those 12 cores cost? And then what am I going to not be able to do? Will I be able to get rid of servers? Will I be able to consolidate?

We can't just ask for the new toys anymore. There has to be a business application for them."

Copyright © 2008 IDG Communications, Inc.

7 inconvenient truths about the hybrid work trend
Shop Tech Products at Amazon