The Evolution of High-End Servers

Despite a tough year in the enterprise server market, big systems continue to show growth—thanks largely to IBM's zSeries. Sun and HP, among others, are in hot pursuit.

No doubt about it, 2001 was a brutal year for computer manufacturers. The high-end server space took a hard hit as well, regardless of having been the most lucrative market segment over the past five years (see "Sliding Server Sales"). IBM Corp. managed to record impressive growth, with a sharp increase in 64-bit zSeries mainframe sales, its fourth consecutive quarter of revenue growth since debuting early last year. According to IDC, strong zSeries sales enabled IBM to increase its share of the high-end server space by almost 10 percentage points in 2001.

Sliding Server Sales Bar GraphFor their parts, Sun Microsysems Inc., Hewlett-Packard Co. and Compaq Computer Corp. have for quite some time shipped 64-bit microprocessors with their Unix operating systems. IBM wedded AIX (its Unix operating system variant) to the 64-bit Power microprocessor. It was a happy marriage: Big Blue has had popular systems based on 64-bit AIX for several years. It wasn't until 2001, however, that IBM finally delivered a 64-bit mainframe environment, and with the 64-bit zSeries, the high-end server market became—at long last—the almost complete provenance of the 64-bit behemoths. By Q1 2002, more than 90 percent of all new high-end servers ran on 64-bit hardware and were sold with a 64-bit operating system, according to IDC's Server Tracker information service.

To be sure, zSeries sales were buoyed by the withdrawal of traditional players Amdahl Corp. and Hitachi Data Systems from the mainframe market and a boost from pent-up demand for the most radically redesigned mainframe line since IBM introduced its 31-bit XA architecture in the 1980s. But there's more to it than that. If recent market trends are any indication, the venerable mainframe still has plenty of kick in the high-end server space.

It's Not About Speed
What accounts for the popularity of the zSeries?

High-end server space doesn't always belong to the fastest microprocessor on the block, suggests Nathan Brookwood, a principal analyst with semiconductor consultancy InSight64.

Consider, for example, the curious case of Compaq's 64-bit Alpha processor. Throughout most of the 1990s, Alpha was the fastest microprocessor in the world and yet sold poorly overall. Conversely, Sun's UltraSPARC 3 microprocessor, which powers its huge 64- and 106-processor SunFire servers, is arguably inferior to HP's PA-RISC, IBM's Power, Compaq's Alpha and even Intel's Itanium 2 microprocessors. Despite that, according to IDC, Sun is second only to IBM in terms of worldwide market share in the high-end server space.

Raw computational performance achieved by some high-end Unix systems—such as Sun's SunFire and HP's Superdome servers—may outstrip the capabilities of the typical S/390 or zSeries mainframe. "In terms of looking at gross throughput capabilities, open systems have probably pretty much caught up with the mainframe in terms of CPU-intensive workloads," acknowledges Richard Fichera, a research fellow and vice president with consultancy Giga Information Group. "In fact, in terms of raw processing power, open systems probably do [outstrip mainframes]."

The Mainframe's Advantage
Raw processing power is only part of the equation, however, asserts Tony Iams, a senior analyst with market research firm D.H. Brown Associates. Iams notes it's difficult to compare the computational performance of a symmetric multiprocessing (SMP) Unix server with that of a massively parallel processing (MPP) mainframe. Very few (if any) Unix environments can match the I/O performance of an S/390 or zSeries mainframe, he says.

Iams adds that Unix systems have yet to match the workload partitioning and batch processing capabilities of IBM mainframe environments, to say nothing of the integration, reliability and manageability that have been part-and-parcel of the mainframe experience for decades.

Not surprisingly, David Chew, director of WebSphere enterprise transaction systems with IBM, agrees. "Typically, mainframes have been very high-transaction engines," he says, noting that mainframes also have several quality-of-service attributes that don't come with the other platforms. "That's typically where the greatest value comes from the mainframe environment," he asserts.

Among other performance-friendly attributes, Chew cites the massive MPP architecture of S/390 and zSeries mainframes, which assures linear scalability as additional processors are added to a system. In a typical SMP configuration, scalability is not linear, but tends to taper off as processors are added and overall memory bandwidth and I/O throughput become saturated.

"The mainframe offers by far the highest transaction-per-second processing level that we have. And part of the reason is because you have linear performance improvements, so as you move up the CPU scale you get linear progressive performance," he observes.

As a result, concludes Giga's Fichera, mainframe systems are still the de facto choice for transaction-based and other computationally intensive mission-critical computing applications. "For the very largest transaction-intensive workloads, people still go with the very highest of high-end systems on the mainframe," he says. "This is because people that are looking for very high-end transaction processing systems can't find an open system that satisfies their requirements for scalability or availability."

WebSphere of Influence
Scalability and reliability alone can't explain how IBM ruled the high-end server roost in 2001, when its mainframes accounted for 36.5 percent of all high-end server revenues compared to 32.9 percent for all non-IBM Unix flavors.

D.H. Brown's Iams says sales probably benefited as well from work that IBM has done to retain existing S/390 customers. After all, Big Blue has done much to make the mainframe an attractive platform for a variety of implementation tasks, from application integration scenarios to server consolidation strategies.

Take IBM's WebSphere application server, for example. For an organization such as The American Family Life Insurance Co., otherwise known as AFLAC, WebSphere is an acceptable tool for application integration. AFLAC uses WebSphere 4.01 running on top of an S/390 mainframe to connect a legacy application—written in S/360 assembly language—to a new business application. In a perfect world, says Rob McCurley, AFLAC vice president of software research, AFLAC would simply have purchased a new off-the-shelf package to replace its legacy application.

"We didn't find a suitable replacement package, and we couldn't buy anything off-the-shelf. And we get value out of it. So the decision was made to rejuvenate it," he says.

AFLAC plans to take its new WebSphere-based application live sometime this fall. As far as McCurley is concerned, WebSphere is a good choice for IT organizations that want to extract additional value from their existing mainframe investments. "It's a very usable tool," he confirms.

But far from merely placating existing accounts, says IBM's Chew, WebSphere—along with the wunderkind operating system Linux—are actually helping to win new accounts for zSeries.

"We do have some new customers who are buying mainframes just to deploy WebSphere," Chew says. "Most of the customer set is the existing [customers], of course. But because of WebSphere, and also because of some of the Linux server activity that's going on, where customers want to consolidate all of their Linux servers, they're really seeing the advantage of the mainframe environment."

The Secret of Staying Power
The secret of the mainframe's staying power is a no-brainer as far as Christophe Vystrecil is concerned.

The business systems analyst with French multi-national manufacturing giant Michelin Group currently leads a zOS-based b-to-b development effort that exploits IBM's WebSphere application server. When Michelin compared the performance and features of IBM's zSeries mainframes against systems from competitors, Big Blue clearly came out on top. Part of the reason, Vystrecil admits, is that Michelin is already a mainframe shop, with both DB2 and CICS in-house. At the same time, he asserts, zSeries technology also outperforms competitors in key areas such as batch processing, real-time transaction processing, reliability and availability.

"We compared benchmarks between IBM and its competition. Regarding the benchmarks between IBM and others, we have chosen IBM," Vystrecil says. "Regarding the performance, regarding the ability to manage the real-time transactions, regarding the knowledge and the skills we need to manage [the application], it was clearly IBM."

It's because of this, says InSight64's Brookwood, that mainframe systems, and, in particular, S/390 and zSeries mainframes from IBM, still delimit the very upper echelon of the high-end server market—despite the success in some environments of high-end SMP systems from Unix vendors such as Sun, Compaq, HP and IBM itself.

"In comparison with open systems [such as systems from Unix vendors]," Brookwood says, "the strength of the mainframe is much more about its ability to accommodate multiprocessor architectures and the I/O architectures, and of course the data integrity features."

Linux and Server Consolidation
It's precisely in this regard that IBM has positioned its zSeries mainframes and iSeries midrange servers as robust platforms for server consolidation. According to Brookwood, the premise behind IBM's server consolidation strategy is simple: Customers who already have S/390 or zSeries mainframes with unused capacity can extract additional value from them by consolidating multiple Linux servers onto discrete logical partitions. In the same way, customers faced with an overabundance of Linux boxes could implement a new zSeries mainframe—or a less expensive iSeries midrange server—to aggregate them all onto a single system.

Among customers who have spare mainframe capacity, says Giga's Fichera, Linux has been a popular alternative—especially as a tool for server consolidation. "The server consolidation [to] Linux on mainframes, that's gotten surprising traction among the people we've talked to. A lot of people are using it. These are people who have spare mainframe capacity and who want to run Linux," he indicates. "In terms of absolute numbers, there are still only a few hundred of these things out there. But I'm talking with a lot of people who believe that it's getting some traction."

Linux's zSeries Impact
It's difficult to assess the effect that Linux has had in driving new zSeries revenues, however. IBM first announced support for Linux on its S/390 mainframe platform in 2000, during a year in which IDC found that OS/390-derived revenues declined by over 10 percent. Part of this decline, says IDC research director Stephen Josselyn, can be attributed to customers who defrayed the purchase of S/390 systems in anticipation of new 64-bit zSeries mainframes. On the other hand, mainframe sales recovered in 2001, partly driven by customers who waited throughout 2000 for IBM to ship the new zSeries mainframes.

How much, if any, zSeries revenues were derived as a result of Linux? He doesn't have immediate numbers to share, but IBM's Chew claims that "we've seen a lot of success in [the Linux] space as well, especially from a server consolidation side."

Big Blue also supports Linux on its iSeries midrange servers. Until recently, market share for the iSeries (which in a previous incarnation was known and loved as the AS/400) was on the decline. Since 2000, however, iSeries market share has grown (see "iSeries Market Share"), increasing even during a tough 2001—driven, suggests IDC's Josselyn, by demand for IBM's high-end model 840 systems for use in server consolidation efforts.

iSeries Market Share

Sun in Second
Among Unix market vendors, Sun ranked second only to IBM in 2001, grabbing 21.9 percent of worldwide market revenues. It's worth noting, however, that Sun actually surpassed IBM in terms of worldwide market revenue in 1999 and 2000.

The tough economy is responsible to some extent for Sun's decline in the high-end server space—between 2000 and 2001, the Unix kingpin experienced a year-over-year revenue drop of almost 40 percent. But according to InSight64's Brookwood, Sun's aging 64-processor Enterprise 10000 (E10000) server—introduced in 1997—is also partially to blame. By 2001, the E10000 had simply run out of gas, Brookwood observes, and was outperformed by new systems from HP and IBM, among others.

That's not to say that it didn't break new ground during its heyday. According to Iams, the E10000 was arguably the first Unix-based system that offered some of the same features—such as workload partitioning—of an S/390 mainframe. "That was really the first Unix system that was able to manage some of these mainframe functions, in particular the capability to partition the server into discrete units. This was the closest thing to LPARs that anyone had introduced in the Unix space," he comments.

Sun refreshed its high-end server line in September 2001 by replacing the E10000 with its SunFire 15000 (SunFire 15K, also known as the StarCat 15000), a high-end SMP server that could scale to 106 processors. In April 2002, Sun followed up its announcement of the SunFire 15K with the SunFire 12K, a 64-processor variant that could be hot-upgraded to 106 processors.

Chris Kruell, group marketing manager for enterprise system products at Sun, maintains that the SunFire 15K is the equivalent of a Unix mainframe. "With the SunFire 15K, we really have to think about that as a modern mainframe," he contends. "Its I/O throughput is phenomenal, second to none. It has system partitioning and hardware partitioning [capabilities]. It can scale to 106 UltraSPARC 3 processors."

Like other vendors in the high-end space, Sun positions the SunFire 15K as an ideal tool for server consolidation. Because Sun only officially supports Solaris on its hardware, Kruell concedes, it envisions a scenario in which an IT organization consolidates multiple, distributed Solaris servers on a single SunFire 15K.

Sun also has its eye on the mainframe space, however. In September 2001, Sun acquired technology from software vendor Critical Path Inc. that it says makes it possible for a SunFire 12K or 15K running Solaris to "host" mainframe applications. Chief among the technologies Sun acquired from Critical Path was UniKix (subsequently renamed Sun Mainframe Transaction Processing Software), an implementation of CICS for open systems.

"We're able to re-host legacy apps for people who don't want to do a full migration. You can now take COBOL code and run it on the Solaris environment," Kruell claims.

In June, 2002, Sun announced that 300 enterprise IT organizations had collectively moved 500 million lines of COBOL code to Solaris.

HP Poised to Win Big?
Although it ranked a distant fifth (see "Worldwide High-End Server Revenue Share (2001)") in worldwide high-end server revenue last year, HP could be poised to dramatically increase its share in the high-end space.

Worldwide High-End Server Revenue Share (2001)

HP's current high-end server entry is the Superdome, a 64-processor system based on the company's PA-RISC 64-bit architecture. Launched in September 2000, Superdome got off to a slow start that was further offset by the economic downturn. Even though HP's PA-RISC architecture outperforms Sun's UltraSPARC 3 processor, HP hasn't made up much ground at Sun's expense. HP has also been involved from a very early date with the development of Intel's 64-bit Itanium microprocessor.

By virtue of its acquisition of Compaq Computer Corp., however, HP will acquire two high-end server platforms, the Non-Stop Himalaya Platform (which Compaq picked up when it purchased Tandem Computers in 1997) and Compaq's AlphaServer line. In addition, HP will inherit the MIPS microprocessor that's currently used by Compaq's Non-Stop Himalaya systems, and must also assume the role of estate planner for Compaq's moribund Alpha microprocessor architecture as well.

More on Enterprise Servers

Three trends are rocking the industry: significant hardware improvements, the open-source movement and difficult economic times. How has this affected high-end servers? And what role can blade servers play in your datacenter?

For the answers, read "Three Enterprise Server Trends."

That makes three microprocessor architectures—PA-RISC, MIPS and Alpha—that HP must manage into retirement. According to Brookwood, HP plans to allow all four architectures—Itanium 2 is the fourth—to co-exist for quite some time. Over the next few years, HP will introduce new systems based on PA-RISC and Alpha. At the same time, HP plans to aggressively ramp-up production of Itanium 2. In 16 months, Brookwood says, HP will debut a new version of PA-RISC that will make it possible for HP to mix and match PA-RISC and Itanium 2 processors in the same server. This could be ideal, Brookwood speculates, for server consolidation scenarios in which a customer wants to deploy HP's HP-UX Unix operating system and aggregate multiple Linux or Windows operating systems.

And Fujitsu-Siemens Makes Four
Since it was formed as a result of the merger of Fujitsu Europe with Siemens World Wide, the combined Fujitsu-Siemens has demonstrated consistent growth. In 2001, IDC indicates that Fujitsu-Siemens captured 4.1 percent of the worldwide market for high-end server revenue, and recorded a year-over-year increase in revenue of 56 percent between 2000 and 2001.

Fujitsu-Siemens currently markets two high-end platforms, the PrimePower 2000—a computational powerhouse that features up to 128 UltraSPARC III microprocessors—and the BS2000 mainframe server, which also leverages UltraSPARC III.

According to D.H. Brown's Iams, although the capabilities of the UltraSPARC III microprocessor are outstripped by competitive RISC offerings from IBM and HP, among others, Fujitsu-Siemens nevertheless markets a highly scalable platform in the PrimePower 2000. "They're able to support more processors [128 versus 106] than Sun, and they offer a lot of the same capabilities [as the high-end SunFire 15K]," Iams indicates.

Fujitsu-Siemens can also host a range of operating system platforms—including Solaris 2.9—on its PrimePower 2000 hardware. The PrimePower 2000 ships by default with the company's ReliantUNIX operating system.

In addition to operating system extensibility, Fujitsu-Siemens lets customers mix processors of different speeds in the context of a single PrimePower 2000 or BS2000 mainframe system. "Fujitsu … has built even larger systems based on the SPARC architecture. They let you mix processor speeds, so you can upgrade your hardware as newer, faster chips become available," Iams says.

The result is that Fujitsu-Siemens can offer customers both a scalable platform for scientific and compute-intensive applications (PrimePower series Unix servers), along with a robust mainframe operating system environment (BS2000 mainframe servers). As D.H. Brown's Iams points out, this gives Fujitsu-Siemens an effective one-two combination that it can sell into almost any high-end enterprise environment.

Unisys' Three-Step
Unisys Corp. is a special case. According to IDC, it trails upstart Fujitsu-Siemens with 3.5 percent of the worldwide market for high-end server revenue. Between 2000 and 2001, Unisys also posted a year-over-year revenue loss of almost 37 percent. Nevertheless, Unisys markets a high-end server—the 32-processor ES7000—that makes it possible for IT organizations to simultaneously host mainframe, Windows and Unix systems on the same hardware. Not even IBM can make such a claim.

If a market for mainframe-class Windows 2000 servers ever materializes, says Mark Feverston, vice president of enterprise server marketing at Unisys, the ES7000 will be the platform to beat. After all, as pervasive as Windows is, the ES7000 is the only server consolidation platform of greater than 16 processors that's currently available to IT organizations.

"We're in a market that's still emerging, and that's the large-scale Windows datacenter environment. There wasn't a market for this two years ago, and we announced the ES7000 roughly two years ago. So we're pretty much forging ahead in that marketplace," Feverston says.

Unisys positions the ES7000 as a strong candidate for a server consolidation platform. It touts the ES7000's unique workload partitioning, system partitioning and self-healing capabilities, and says that it's been able to achieve all of this—plus a high level of availability—while running on industry-standard Intel hardware.

As far as D.H. Brown's Iams is concerned, the ES7000 constitutes a bona fide Intel architecture mainframe. "The hardware is outstanding. It's very hard to find flaws in the hardware. This is truly a mainframe based on Intel, and they have done everything possible to push the software capabilities so that it can exploit the hardware," he comments.

The ES7000 can run Unisys' ClearPath mainframe operating systems, Windows 2000 Datacenter Server and OpenUnix 8 from Caldera International Inc. It can run all three operating systems across a mixture of 32-bit and 64-bit Intel partitions, which, Feverston points out, makes it an ideal choice for an organization that doesn't want to commit completely to Itanium 2, but which also doesn't want to be left behind as the industry moves to 64-bit platforms.

Feverston says Unisys has sold "about 700" ES7000s since the company first began shipping them in late 2000. "Approximately 40 percent of our sales will be to brand new customers, those who have not been with Unisys before. Of course, that means that the bulk of those are going to existing ES7000 users."

A Year Like Last Year?
Last year was tough for purveyors of enterprise servers. IBM, which leads a pack that includes Sun, HP and Unisys, continues to see the high-end market as brimming with potential. Tough economic times, huge leaps in hardware technology, and the advent of Linux also are stirring the pot. Who continues to dominate in the lucrative high-end server market remains to be seen.