Increasing consumption of electrical power posing threat to Moore's Law.
The only things rising faster than the temperatures in corporate server rooms over the last 15 years have been IT departments electricity bills. Both can be traced largely to a persistent and growing use of ever-more-powerful processors in the workplace.
Since 1985, the appetite of Intel Corp.s top-of-the-line processors has soared from the single watt required by a 20MHz 80386 to the 75 watts consumed by todays 800MHz Pentium III, the favored CPU for Intel-based rack servers. Intels Itanium processor draws 100 watts. And since it takes 0.6 watts of air conditioning to remove the heat produced by every 1 watt of computing power, the total electricity demand per CPU has jumped by a multiple of more than 120 since 1985.
The heat issue alone is seriously threatening Moores Lawwhich predicts a doubling of computing power every 12 to 18 monthsfor the simple reason that heat causes semiconductor materials to behave erratically. As semiconductors continue to grow in complexity and performance gains are realized by continually shrinking transistor sizes, heat becomes an ever-more-limiting factor in the pace of chip design and fabrication.
By the end of this decade, if heat-to-performance ratios cannot be improved significantly, chip makers predict the exponential increases in computing power that marked the 1980s and 1990s will wither awayas will the economic expansion the Federal Reserve and a number of economists have credited to productivity gains realized in the computerization of the workplace.
Its a situation that IT managers are now factoring into their decisions on server hardware and overall budget estimates. "When youre paying $200 a month for a 20-amp, 120-volt power circuit, it depends on your cage, of course, but you could easily drop four or five of those to one rack of gear, so youre looking at $1,000 a month, per rack, just for power," said Dwight Gibbs, former IT manager for The Motley Fool Inc. financial Web site, in Herndon, Va., and now an IT consultant.
"A lot of the IT folks are looking at this as a facilities issue because thats the budget its in," Gibbs said. "But what do you think the facilities people are saying? Theyre screaming bloody murder because basically theyre getting killed on costs. And the IT guys are saying, Look, I just need the power."
Chip manufacturers are taking note. Long content with allowing power consumption to increase in tandem with processor performance, leading semiconductor companies have recently placed new emphasis on reducing power consumption. But dont expect server rooms to go "green" overnight. Even if vendors deliver on their promises, it will take the better part of a decade to replace the generations of legacy processors already in service.
Intel, the largest microprocessor maker, has a track record that is generally in line with those of its competitors, although architectural issues and alternative ways of rating power consumption make direct comparisons of the total wattage drawn by various processors almost impossible. For example, Sun Microsystems Inc. rates its UltraSPARC IIe at only 10 watts when running at 500MHz, but, like all RISC processors, it requires more cache memory, which simply shifts power consumption to another part of the system.
Jay Stein, an analyst at E Source, a Boulder, Colo., provider of research information to electric and gas utilities, said he sees these inefficiencies as unavoidable given the demands of the market. "The customers are telling the manufacturers they want more functionality jammed in per cubic foot," Stein said, "and the manufacturers have been succeeding at the compaction game faster than theyve been able to increase the efficiency of the equipment."
For the kind of trouble this lag could cause, look no further than California. That states energy problems, though unique for a number of reasons, were nevertheless a preview of the energy challenges data centers, server farms and large IT operations are likely to face in the near future.
Stein, who this month will publish a report for electric utilities titled "Delivering Energy Services to Internet Hotels and Other High-Density Electronic Loads," said that unless processor design becomes a lot more efficient, growth in the technology sector will come to a halt for two reasons: The existing wiring of most buildings is not designed for the load, and utilities simply wont be able to handle the demand.
"Were this trend to continue," Stein said, "virtually all the data space thats out there right now would become rapidly obsolete, and it would be almost impossible to build any new space because youd go into the utilities and ask for so much power that theyd toss you out. Theyd say, Forget it, theres no way we can get you that much power."
In fact, Dan McDunn, computer services director for Alaska Airlines Inc., based in Seattle, said that in some ways, his data space is already obsolete. "With 10 to 15 racks of computers, how do we run power to them in a nice, clean way?" McDunn asked. "Over the long run, I dont think anyone has stepped up with a solution for how you supply power to high-density units."
Although supplying power to server racks has its problems, McDunn said he has seen an enormous drop in "environmentals"the combined costs of the equipments electrical consumption and coolingas old power-hogging mainframes were replaced with more efficient models or with Intel-based servers.
If many IT departments have yet to take note of the increasing power appetites of Pentium-class processors, it may be because, like McDunn, theyre still celebrating huge power savings over old mainframe technology. But while mainframe-replacement efficiencies are likely to continue improving, the environmentals for any IT operation dependent on Pentium-class servers are going to get worse before they get better.
As the power used by semiconductors increases, so does the amount of heat they produce, which, in turn, pushes up cooling costs. According to marketing data from server maker RLX Technologies Inc., of The Woodlands, Texas, the average dual-processor, Pentium III-based server produces about 2.3 million British thermal units per year. That turns out to be about as much heat as a typical home furnace produces running continuously for 28 hours. The annual heat output of a 42-unit rack of dual-processor "pizza box" servers could heat a small home in the Northeast for six weeks in the dead of winter.
Whats more, considerable capital costs are typically incurred in direct proportion to increased power demands by computers, especially in mission-critical applications. In addition to air conditioning and other cooling equipment, these include uninterruptible power supplies and backup generators along with the diesel fuel to run them. And though backup generators rarely kick in, they were required frequently during Californias rolling blackouts.
Fortunately so far, rising demand for power has coincided with declining electricity prices. By the end of 2000, the average commercial cost of electricity per kilowatt-hour had dropped to 7.20 cents from 7.27 cents in 1985, according to the federal Energy Information Administration, a division of the U.S. Department of Energy. When inflation adjustments are factored in, the real cost of commercial power dropped more than 3 cents per kilowatt-hour, or about 32 percent, during that time.
But costs may prove less important in the long run than availability.
"You start adding this stuff up, and it is just crazy," Gibbs said. "Just ask the folks in California. The choice they were basically left with was, Were going to run generators 24-by-7, or were going to move somewhere else."
Kevin Teixeira, a spokesman for Intel Labs, the chip makers research and development division, said Californias rolling blackouts through the heart of Silicon Valley, coupled with Pacific Gas & Electric Corp.s warnings to large data centers and server farms to put any expansion plans on hold, served as a wake-up call for chip makers. Teixeira said it brought home to Intel the fact that "in the Internet era and with companies reorganizing themselves to integrate electronic processes into the very fabric of how they do business, [processor power consumption] becomes a systemic issue, an issue of the whole ecology."
Teixeira also insisted that Intel would have been addressing power consumption issues even "if the California energy crisis hadnt come along. This is inherent to the industry," he said. "As we pursue Moores Law, putting more chips on a die and squeezing more transistors into the die, this is something we are having to tackle."
For Intel, whose competitive battles have generally been fought at the megahertz level, power consumption is a high-level engineering problem that will be solved over time the way Intel has always achieved progressthrough new designs, materials and fabrication techniques. While the Santa Clara, Calif., company has made advances in fits and starts over the last year, promises of sizable gains in processor efficiency are years away. For example, its terahertz transistor, which cuts energy consumption about 30 percent, was announced last year but will probably not be a factor in the companys products until at least middecade.
Meanwhile, David Ditzel said he already has the answera processor that achieves remarkable efficiencies in both mobile devices, for which it was designed, and in rack server configurations, for which it has been adopted. Ditzel is founder and chief technology officer of Transmeta Corp., also of Santa Clara, which makes the low- power Crusoe processor.
"In the California case, a number of big [service] providers were told they couldnt expand because they couldnt take any more power out of the grid," Ditzel said. "Their only option is a solution like the Crusoe, where you get more computing power per watt."
A lot more, in fact. The Crusoe draws about one-fifth the power of its closest Intel counterpart, the ultra-low-voltage Pentium III for mobile computers. Whats more, Crusoes size and thermal properties enable server makers to employ eight times as many processors per square foot, reducing space and cooling demands. It does this by offloading the prioritization and ordering of instructions to software, thus greatly reducing the number of transistors, and by throttling back power consumption when maximum processing power is not required. It was the first processor to achieve the U.S. governments Energy Star award.
In the meantime, the rest of the industry is not standing still. Transmetas introduction of the Crusoe touched off industrywide competition, sometimes fierce, to reduce power consumption and heat generation. Intel fired its first volley last spring with the introduction of a line of more efficient mobile Pentiums and Celerons, and while the Pentium 4, which debuted this month, with its 42 million transistors is a bigger energy glutton than its predecessors, there is no question the company is committed to improved efficiency in the long run.
As early as a year ago, Pat Gelsinger, Intels CTO, told top chip designers gathered for the International Solid-State Circuits Conference that managing power would be the single greatest challenge his company faced.
IBM, too, has made efficiency a top priority. In an October press release, it announced that its forthcoming PowerPC 405LP processor would be "capable of ultra-low-power operation, providing a glimpse of the many innovative technologies the company has in the pipeline to reduce power consumption in electronic products."
Several small companies are also vying for a piece of the low-energy processor market. These include VIA Technologies Inc. of Taipei, Taiwan, which makes an ultra-low-voltage processor, the C3, and Egenera Inc., of Marlboro, Mass., whose BladeFrame server design reduces power consumption by eliminating traditional I/O devices and consolidating components.
The industrys big question mark is Sun, which has declined to reveal its power management strategy in future chip design. Industry insiders said Sun has privately told customers they can expect sizable power efficiencies in the future.
Yet today, Transmeta, despite financial and manufacturing problems, is the only company delivering major efficiency improvements in an industry that is otherwise producing a lot of promises but few tangible results. "They havent felt enough pain yet," Stein said of the industry in general. But he insisted the industry will eventually feel the power crunch in ways companies cant ignore.