After more than a year's delay, Intel recently released its Itanium chip to OEMs such as Dell, Hewlett-Packard (HP), and IBM, making 64-bit Wintel systems a reality. To coincide with the initial Itanium release, Microsoft in the third quarter is providing two 64-bit versions of Windows: the 64-bit Windows Advanced Server, Limited Edition on the server side and Windows XP 64-Bit Edition on the client side. A 64-bit version of SQL Server 2000 will be the first Microsoft server product available as a native 64-bit application.

The 64-bit Windows platform will provide up to 16TB of flat virtual address space and will increase the paging file to 512TB and the system cache to 1TB. The Limited Edition server, based on Whistler Advanced Server, will support up to eight processors. For the most part, the 64-bit versions of Windows will look and feel like Windows XP. Out of the gate, however, 64-bit Windows won't support 16-bit DOS applications and will lack Windows Product Activation, NetMeeting, Windows Media Player (WMP), Remote Assistance, and Power Management. In addition, these 64-bit versions will be available only from OEMs.

So, is this first-generation Itanium chip right for SQL Server implementations? Probably not. Although the chip provides substantially more memory capacity, the CPU probably won't provide the processing power of today's high-end 32-bit processors for typical business applications. Initial releases of the fastest Itanium systems will run at a maximum of 800MHz, which is substantially slower than the 1.7GHz-plus speeds set by the current crop of 32-bit Intel Pentium and AMD Athlon chips. The other major performance factor is compiler efficiency. Itanium's Explicitly Parallel Instruction Computing (EPIC) architecture relies on the compiler to set up and optimize instructions fed to the processor. But with the 64-bit Microsoft compilers all at version 1, there's tremendous room for improvement.

Need another reason to wait? Although Itanium-based systems can run 32-bit applications by using Windows on Windows 64 (WOW64) technology, Itanium runs 32-bit applications by using x86 instruction-set emulation, which imposes a significant performance penalty. Microsoft doesn't recommend running current 32-bit servers—including SQL Server 2000 and Exchange Server 2000—on Itanium systems.

The first Itanium systems seem best suited for scientific, digital-graphics, and animation applications. These applications usually have prodigious memory requirements and would benefit from Itanium's parallel-processing architecture. For databases, Itanium's large memory capacity and strong numeric computational power make it a good fit for data mining and analysis applications. Although the chip's increased memory capacity lends itself to very large database (VLDB) implementations, Itanium's limited SMP support and modest clock speeds keep it from being a must-have in these environments.

Although today's Itanium might not be a great choice for most database implementations, the 64-bit landscape is evolving quickly. Intel's next 64-bit platform, code-named McKinley, will boost clock speeds to greater than 1GHz, vastly expanding potential implementations of this new 64-bit architecture.