April 7, 2004, 4:00 AM PT
The S/360, the computer that spawned IBM's mainframe line, turns 40 on Wednesday—but it's not wallowing in a midlife crisis.
Although some pundits regularly declare the death of the mainframe, the world has not yet seen the last of the industrial, freezer-size computers used to coordinate the work of brokerage firms and NASA alike. Amdahl and some competitors might be gone, but IBM and a few others are still around.
IBM launched the modern mainframe with the S/360 in 1964. And for Big Blue, four decades on, descendants of that system are still paying dividends. Last year, the company sold 2,700 mainframes for $4.3 billion in revenue, according to IDC. That was up from 2,300 systems and $4 billion in 2002, despite predictions that mainframe revenue would start declining. Last year, these machines made up about one-third of the industry total of servers priced at more than $500,000, and accounted for about one-third of IBM's server revenue.
Mainframe hardware sales constitute about 5 percent of IBM's overall revenue. But when services and software are factored in, mainframe-related sales likely contribute around 25 percent of revenue and close to 45 percent of operating profit, according to some estimates.
"People say the mainframe is dead," said Vernon Turner, an analyst at IDC, "but we say, hmmm, that's a $4.5 billion tombstone."
IBM is also modernizing its line to better compete with high-end Unix- and Intel-based servers. To commemorate the 40th anniversary of the IBM S/360, the company Wednesday unveiled the z890 mainframe. Aimed at midsize customers, the machine starts below $200,000, a price that hasn't been seen much since the 1960s.
The company also released an optional module for running Java server applications and a complementary midrange storage system. The Linux operating system started to creep onto IBM mainframes in 2000.
Several early mainframe pioneers are expected to gather at the Computer History Museum in Mountain View, Calif., later on Wednesday to celebrate the anniversary.
Yesterday's next big thing
To many, mainframes—which in earlier times took up entire rooms and had water-cooled processors—epitomize industrial chic. But the machines were quite revolutionary when they debuted in 1964. At the time, computer jobs were tackled one at a time, typically by people in white lab coats.
By contrast, the S/360 and the subsequent raft of machines from IBM, NCR, Sperry and others allowed different applications to be run simultaneously. This had the dual effect of reducing the cost and spreading the pervasiveness of corporate computing.
"Prior to the S/360, each computer was a unique system. They were made to an individual customer's order, and there was no continuity from design to design," said Colette Martin, the director of zSeries products for IBM. "Prior to the S/360, they were single-application systems."
Today, the main selling point of IBM's mainframes, which typically start at around $1 million, largely lies in holistic performance. The mainframes don't offer the same sort of benchmark results or megahertz ratings of high-end Unix servers like the Superdome line from Hewlett-Packard or Sun's Sun Fire. IBM, in fact, doesn't submit its mainframes to the commonly used TPC-C benchmark tests.
The Unix servers from HP and Sun (or IBM for that matter) also tend to be made with more commonly available components, which can help drive down the acquisition and management costs over time. IBM is integrating more common parts into its z line of mainframes (which succeeded the S line in 2000), but the series still features a processor not found in other computers, the company's own z/OS operating system, its own file system and a distinct method for formatting hard drives, among other singularities.
The extra expense associated with the distinct personality of mainframes from any manufacturer has led many customers to embrace Unix/RISC-based servers and (to a lesser, but growing, extent) Intel-based servers for their most complex computing jobs.
"I think we are at a point where the mainframe scale and reliability can be accomplished through 'loosely coupled' open systems using database engines, large disk arrays and application server farms," Glenn Bonner, the chief information officer at MGM Mirage, wrote in an e-mail interview. "Scalability is near limitless with these architectures, without the big upgrade times needed to 'fork-lift' an OS390 environment. Hence, I believe mainframes are here today because of legacy applications."
Bonner, who started his programming career on the S/360, has phased out most of the applications running on MGM's Tandem computers (a type of mainframe made by HP) in favor of relatively standardized servers running a Microsoft .Net application.
On the other hand, the distinctive nature of these systems means that they often excel in real-world installations. A cluster based on IBM's latest mainframe, the z990, can handle 13 billion transactions a day, according to Big Blue. Statistically, an IBM mainframe should go down only once every 50 years or so, according to Charles King, an analyst at the Sageza Group. For a multinational bank, that's probably an important number.
Security is also often better on a mainframe than on large conventional servers, King added. That's because different partitions, or virtual servers within a larger physical one, can be more completely segregated from each other, he said. Background functions, such as backup data, can occur without degrading the performance of other applications comparatively well.
"IBM didn't let it go out of date," King said. "The mainframe's real strength is in its flexibility and its ability to do several things at once."
Software and standards
In addition to producing revenue, the mainframe has served as a font of ideas. The Customer Information Control System became the basis for transaction-processing systems, while the Information Management System, developed for the first flight to the moon, was a forerunner of IBM's database business, according to the company.
More recently, a substantial portion of the technology behind IBM's autonomic computing initiative, which seeks to create computers and networks that can detect and cure their own problems, has come out of IBM's mainframe line. In the future, mainframe technology is expected to head toward blade servers.
The lack of cheaper server lines to help amortize some of the R&D investment in mainframes led, in part, to the demise of many of IBM's mainframe competitors, said Jonathan Eunice, an analyst at Illuminata.
Conversely, IBM's ability to exploit its tribal knowledge of the older systems to generate other products was one of the reasons that mainframes got spared when former CEO Lou Gerstner retrofitted an torpid IBM in the mid-1990s.
"The mainframe guys said, 'Geez, we have to do something,'" Eunice said. "They really got whacked for a customer-insensitive attitude."
Ironically, the IBM mainframe—which is often held up as an example of proprietary architecture—also helped usher in the concept of standards, according to both Turner and Eunice, because the same software could be found on more than one computer. Both Amdahl and Hitachi were able to make "plug compatible" mainframes on IBM licenses. The hardware was different, but the software was virtually the same.
"The IBM mainframe was the first time we saw a major standard in computing," Eunice said. "Compared to the world it came into, it was amazingly standard and modular. No one else had heard of compatible software on multiple lines."
Still, the future isn't completely bright. History shows that mainframe functions will get absorbed into smaller, cheaper computers, and the Unix servers and Windows/Linux clusters based on Intel processors will continue to chew up more potential mainframe turf.
Naturally, both Sun and HP agree about this trend, citing customer wins and benchmarks. In the past eight years, Sun has weaned more than 1,000 customers off mainframes—including about 150 in the last year—because of their high costs, said Don Whitehead, the company's director of mainframe migration. Mainframe hardware can cost nearly twice as much as other high-end systems, he said, and software licensing costs can boost operating costs differences even higher. Typically, mainframe customers have to pay a monthly fee to license software, which is a more rapid renewal schedule than for servers.
Training can also be a problem for mainframe customers.
"They don't teach people how to run mainframes in college," Whitehead said. "Most of the mainframe programmers I know are looking at their retirement plans."
On the other hand, at the same time that IBM has seen at least a slight gain in mainframe sales, Sun has wallowed in financial losses.
And Big Blue continues to update the line. In the 1990s, it switched to processors made of standard silicon transistors instead of more-expensive bipolar circuits. In 2000, it came out with its first 64-bit processors for the machines. Software like Linux and IBM's WebSphere are allowing contemporary IT buyers to fit the mainframe into their plans. Among other benefits, the mixing-in of modern software allows IBM to get rid of the "green screen" in favor of a more modern interface.
In five to seven years, the hardware of IBM mainframes may be nearly identical to that of other IBM servers, but could contain an emulation layer that lets them act like mainframes, Eunice hypothesized.
Besides, the future will always bring more complex problems to solve.
"The mainframe is the technology leader. There are a lot of servers out there, but we are always leading the pack," IBM's Martin said. "It really has to do with heavy-duty, bulletproof strengths."