After years of hype, the Advanced Micro Devices (AMD) Opteron 64-bit processor is scheduled to debut this month. The company and its shareholders might curse the rotten timing, but the current contracted market is actually the perfect setting for AMD’s new technology. While other chipmakers scramble to adapt, AMD seems to have designed current business challenges and priorities into its architecture. Considering how long Opteron has been in engineering, AMD is either very smart or very lucky. Opteron may be an opportune solution for customers looking to consolidate their servers and reduce operating costs.
The advantages of AMD’s new design are many. The most talked-about feature is the CPU’s support for 64-bit applications. Unlike previous 64-bit processors, Opteron implements the full x86-32 instruction set. Software that runs on a Pentium III or AMD Athlon now will run unmodified on Opteron. Opteron-based servers will likely spend the majority of their time running the 32-bit Windows and Linux programs that businesses use today.
Software written to exploit Opteron’s 64-bit capabilities will break through the barriers that prevent the x86 from running extremely demanding server and technical applications. A vastly expanded address space (up to 1TB of physical memory), a larger set of high-speed registers, and new instructions, will take affordable servers to a higher level of performance. Running in 64-bit mode, an Opteron application can crunch through mountains of in-memory data and perform blazingly fast data transfers to network and storage devices.
Unlike other x86 processors, the Opteron CPU has the inherent ability to link up to eight processors without specialised chips. Every processor has three HyperTransport bus controllers for fast connections to other CPUs and devices.
Instead of using an external memory controller, that complicates system design and adds latency, AMD links memory directly to each CPU. The design has plenty of headroom to accommodate faster memory and I/O devices. The only speed limit is the 19.2GB per second capacity of each chip’s combined HyperTransport channels, which exceeds the top speed of the most capable PC server bus.
In systems that require more than eight processors, Opteron will rely on external chipsets to provide communications between CPUs. The fact that HyperTransport is already on the chip simplifies the engineering. Systems running two- and four-CPU configurations — which account for most x86 server sales — will ship in 2003. How soon larger systems appear depends entirely on market demand.
Answering critics The chief criticisms leveled against the platform by Intel and critical analysts — mainly that Opteron is immature technology and that Microsoft is dragging its feet porting Windows to it — will prove groundless. The well-respected and thoroughly debugged Athlon x86 processor is the foundation of the Opteron chip.
The remarkable HyperTransport bus that AMD uses to tie Opteron chips to each other and to I/O devices is already in widespread use. The double data rate (DDR) memory that AMD has chosen for its first implementation is inexpensive and readily available. AMD’s chipset implements standard PCI-X and Accelerated Graphics Port (AGP) peripheral buses.
System manufacturers and customers will have relatively few adjustments to make.
The Windows question is slightly trickier, but it isn’t an issue Intel should press too hard. Yes, the sole 64-bit version of Windows runs on Itanium and Itanium 2. However, Microsoft has repeatedly stated that it strongly prefers AMD’s 64-bit architecture to Intel’s.
Opteron is not stuck in the same spot as Intel at the launch of Itanium. Intel had to wait for Microsoft to announce its Itanium-specific port of Windows. Opteron already runs 32-bit Windows at full speed while other 64-bit CPUs must use emulation to run most Windows software.
Microsoft’s engineering task, which it needn’t hurry to accomplish, is to turn on 64-bit support in those parts of its software that would benefit the most. In demonstrations, Microsoft has shown 64-bit editions of Internet Information Server and Terminal server running on Opteron.
The first server to market is one designed by startup Newisys. That is also a source of some controversy. HP is committed to Itanium 2. IBM has said it will wait to see if Opteron catches on (while wisely partnering with AMD to manufacture chips).
Dell is making an enterprise announcement in early April, at which time we expect Dell will take a position on Opteron. But even if it takes a while for AMD to sign on major system vendors, plenty of Opteron systems will be in the channel.
Newisys may be a startup, but it’s no lightweight. Its top brass is stacked with big names from IBM and Microsoft. Integrators building systems from components will be able to buy Opteron building blocks from most of the major motherboard manufacturers.
AMD’s April 22 launch date looks solid. Competitors that are hoping the event will pass with little fanfare are certain to be disappointed. Unless AMD hopelessly botches it, Opteron is going to claim a substantial share of the entry server market.
Opteron’s support for 64-bit operation is not the whole story. The HyperTransport bus, glueless multiprocessor operation (up to eight CPUs), and high-performance paths to memory and I/O will benefit even 32-bit software.