Intel Hedges Its 64-Bit Bet with 32-Bit Support

Progress on 64-bit processors and operating systems for the Wintel market suggest that products will become available within the next two years. Yet both Microsoft Corp. and Intel Corp. are hedging their bets with products that will support 32-bit enterprise systems for a long time to come.

Intel says it is on track to ship samples of Merced, its 64-bit chip being jointly developed with Hewlett-Packard Co., in mid-1999. Production of Merced chips is scheduled to commence in mid-2000, says Fred Pollack, director of measurements, architecture and planning and an Intel Fellow with Intel. In late 2001, Intel and HP will introduce a second-generation 64-bit successor to Merced, code-named McKinley, which will have a clock speed of 1 GHz or more. A shortened pipeline and increased number of execution units will double the performance of McKinley over Merced, Pollack says.

Following McKinley, around the year 2002, Intel will split the market, offering a 64-bit chip code-named Madison to the high end and another, lower-priced 64-bit chip code-named Deerfield to the volume market. Madison and Deerfield will be built on .13 micron architecture, compared with .18 for Merced and McKinley. While Merced and McKinley will be targeted to the high end workstation and server market, Deerfield will open 64-bit computing to the masses, Pollack relates.

The technology in 64-bit systems enables extremely large databases to reside in memory, supporting rapid query access and high-volume transactions. Leading chipmakers -- including Intel, Compaq Computer Corp., Sun Microsystems, IBM Corp., and HP -- have announced their 64-but roadmaps, and in some cases have delivered complete 64-bit capable computer systems running operating systems such as OS/400 and Unix. While Intel is not present in this market, industry analysts project the chipmaker may eventually dominate the commodity market for 64-bit computing running Windows 2000. This evolution, however, may take more than half a decade

"It will be several years at least before 64-bit chips become affordable for midrange kinds of systems," says Michael Goulde, vice president and senior consultant with Patricia Seybold Group (Boston). "The majority of the market will be with 32 bits for quite a while."

The high-end market that Merced and McKinley are aimed at are still dominated by Unix and RISC systems, Pollack says. "IA-32 hasn't penetrated the very high end of the workstation and server market," he explains. "These are systems that cost hundreds of thousands of dollars -- where Microsoft has trouble penetrating as well. They require lots of reliability, availability, serviceability, and scalability."

With widespread 64-bit computing unlikely to pick up until the introduction of Deerfield, Intel is providing a strong roadmap for 32-bit computing. Intel's current Pentium II Xeon processor line will be supplanted by a chip code-named Tanner within the year, attaining a clock speed of 500 MHz. The successor to Tanner, code-named Cascades, and built on .18 micron architecture, will launch in 2000, at about the sale time as Merced.

The 32-bit Foster processor will debut in early 2001, about six months after Merced goes into production, Pollack says. The chip will be based on a new 32-bit microarchitecture that will succeed the P6 microarchitecture. Along with enhanced parallel execution of programs, "Foster has a pipeline that's deeper than P6, which allows us to get higher frequencies such as 1 GHz and beyond," he explains. Additional features include instruction trace cache, which eliminates decoding bottlenecks, and advanced branch prediction to increase execution efficiency. The Foster processor also will have a throughput of 3.2 GBs a second.

Analysts agree that there's still a lot of umph left in 32-bit computing. The Xeon processor "has broken Intel's processor 'mental block' at the high end of the Wintel server space, and overnight has increased high-end Wintel scalability by approximately 50 percent over four-way Pentium Pro-based servers," says Joe Barkan, research director with GartnerGroup (Stamford, Conn.). With such strong IA-32 offerings, IS managers "should not feel any pressure to move to IA-64 platforms at this time," he says. "The IA-32 architecture will continue to evolve through 2002 and will provide enough performance for a large majority of NT-based computing tasks through 2005."

In fact, native 32-bit applications may run much faster on a 32- bit server than a 64-bit machine. "Applications running in 32- bit emulation mode on a 64-bit machine will run slightly slower," says Wayne Kernochan, senior vice president of Aberdeen Group (Boston). "If you recompile the applications, they'll run faster. Only if you rewrite them to take care of the extra instructions will you really see the benefit."

Intel's Pollack agrees that performance of 32-bit applications on Foster will be slightly faster than on Merced. But, "if you have 64-bit applications, clearly, Merced will be faster," he adds.

Microsoft intends to come out with a 64-bit operating system "when the 64-bit chip ships in volume," Barkan says. He advises, however, holding off on 64-bit implementation until the next-generation 64-bit processor, when the platform is proven stable, and 64-bit databases or applications are available. "It's probably not worth doing more than fooling around on 64-bit until the McKinley timeframe," he says. By 2001, "fewer then 15 percent of NT servers sold in 2001 will be Merced-based," he predicts.

*Indeed, implementing 64-bit systems is going to take time and effort. "It's not so much the question of whether a 64-bit version of [Windows 2000] is on time or not, as the fact that it's going to be a massive and complicated upgrade in order to get its real benefit," Kernochan says. "That upgrade is going to take place over the period of a year or more."

Ed Muth, group product manager for Microsoft, urges customers to focus on planning for and implementing Windows 2000. "There's a lot of valuable technology in [Windows 2000] people will want to incorporate quickly into their technical architecture, including the Active Directory and security features," he says. "I would not want customers to get distracted from [Windows 2000]-related work because of a 64-bit version out in the future." In fact, many of the elements of 64-bit computing -- including support for very large memory, or VLM -- are being packaged into Windows 2000 Advanced Server and Datacenter Server, Muth says.

Some analysts are optimistic that the shift to 64-bit computing will be relatively painless from a development standpoint. "The applications that will most likely be the first to move to 64-bit [Windows 2000] are the same ones that adopted 64-bit Unix," Goulde says. "These include ECAD, finite element analysis, statistical packages, and databases. All these applications can use a physical virtual address space. Microsoft probably will not have a complete set of 64-bit BackOffice applications nor a complete 64-bit implementation of all the Enterprise Edition's functionality, but this probably isn't relevant to the majority of applications. NT systems of 32 bits and 64 bits will be able to interoperate without any difficulty, and that will be what customers will look for most."

Another 64-bit platform for which Microsoft is preparing is Compaq's Alpha processor line. Compaq recently unveiled its new EV7 Alpha processor, and announced plans for EV8, EV9 and EV10 chips. But applications specifically tailored for the platform will be sparse, Goulde predicts. "You could fill a room with Alpha programmers."

Compaq may continue to develop and maintain Alpha as a niche in high-end Windows 2000 computing until Merced catches up in performance, which could occur by 2003, Barkan says. "Alpha technology use for Windows NT will live or die according to Compaq's commitment to the technology. We expect Compaq will not be as enthused about Alpha as Digital has been. However, Compaq may consider its ownership of Alpha to be an exploitive opportunity to lead the NT market at the high-end until the arrival of IA-64-based server."